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Sample records for thallium-201 single photon

  1. Indium-111 antimyosin antibody imaging and thallium-201 imaging. A comparative myocardial scintigraphic study using single-photon emission computed tomography in patients with myocarditis and dilated cardiomyopathy

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    Yamada, Takehiko; Matsumori, Akira; Nohara, Ryuji; Konishi, Junji; Sasayama, Shigetake [Kyoto Univ. (Japan). Faculty of Medicine; Tamaki, Nagara

    1997-10-01

    Indium-111 antimyosin antibody imaging (a tracer of myocardial necrosis) and thallium-201 imaging (a tracer of myocardial perfusion) were compared in patients with myocarditis and dilated cardiomyopathy. The distribution of each tracer and antimyosin/thallium-201 overlapping were evaluated with single-photon emission computed tomography (SPECT). Scintigraphic data were classified into 5 patterns according to the distribution of both images and were compared with histologic findings of endomyocardial biopsy: AM-D, intense and diffuse antimyosin uptake and no perfusion abnormality (active myocarditis); AM-L, localized antimyosin uptake and no perfusion abnormality (active myocarditis); HM, no antimyosin uptake with or without perfusion abnormality (healed myocarditis); DCM-NH, diffuse antimyosin uptake and inhomogeneous thallium-201 uptake (dilated cardiomyopathy); DCM-PD, diffuse or localized antimyosin uptake and myocardial perfusion defect(s) (dilated cardiomyopathy). Patients with dilated-phase hypertrophic cardiomyopathy were frequently found in the DCM-PD group. Taken together, comparative antimyosin/thallium-201 SPECT images are useful for evaluating the activity of myocarditis and ongoing myocardial damage even in areas with no perfusion in patients with dilated cardiomyopathy. (author)

  2. Comparison of glucose-insulin-thallium-201 infusion single photon emission computed tomography (SPECT), stress-redistribution-reinjection thallium-201 SPECT and low dose dobutamine echocardiography for prediction of reversible dysfunction

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    Sakamoto, Hiroki; Kondo, Makoto; Motohiro, Masayuki; Usami, Satoru [Shimada Municipal Hospital, Shizuoka (Japan)

    2001-12-01

    The usefulness of glucose-insulin-thallium-201 (GI-Tl) infusion single photon emission computed tomography (SPECT) in predicting reversible dysfunction has not been evaluated, so the present study recruited 20 patients with regional ischemic dysfunction for investigation. All patients underwent GI-Tl SPECT, post-stress Tl reinjection imaging and low dose dobutamine echocardiography. The diagnostic accuracy of these 3 techniques in predicting functional recovery was evaluated by receiver operating characteristic (ROC) analysis. In segments with functional recovery, regional Tl activities of GI-Tl SPECT were significantly higher than those of reinjection imaging (p<0.05), although there were no significant differences in segments without recovery. The area under the ROC curve for GI-Tl SPECT (0.75{+-}0.06) was greater than that for reinjection imaging (0.68{+-}0.07). The optimal cutoff values to identify viable myocardium were considered to be 55% of peak activity for GI-Tl SPECT and 50% for reinjection imaging. At this cutoff point, the sensitivity and specificity for detection of functional recovery were, respectively, 85% and 61% for GI-Tl SPECT, and 73% and 61% for reinjection imaging. Dobutamine echocardiography had the same sensitivity (85%), but lower specificity (48%) than GI-Tl SPECT. Continuous infusion of GI-Tl solution enhances regional Tl uptake compared with conventional post-stress reinjection imaging. This study suggests that GI-Tl SPECT is superior to reinjection imaging and dobutamine echocardiography in predicting functional recovery after ischemic left ventricular dysfunction. (author)

  3. Functional significance of myocardial perfusion defects induced by dipyridamole using thallium-201 single-photon emission computed tomography and two-dimensional echocardiography

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    Jain, A.; Suarez, J.; Mahmarian, J.J.; Zoghbi, W.A.; Quinones, M.A.; Verani, M.S. (Baylor College of Medicine, Houston, TX (USA))

    1990-10-01

    The mechanisms responsible for inhomogeneous myocardial blood flow after oral administration of a large dose (300 mg) of dipyridamole were assessed in 27 patients with serial thallium-201 single-photon emission computed tomography (SPECT) and simultaneous 2-dimensional echocardiograms. Myocardial tomographic images were obtained 50 minutes and 3 to 4 hours after administration of dipyridamole. Two-dimensional echocardiograms were recorded at baseline and then every 15 minutes for 60 minutes. Dipyridamole caused only a mild reduction in blood pressure (from 129 +/- 18 to 126 +/- 16 mm Hg) and a mild increase in heart rate (from 69 +/- 15 to 73 +/- 4 beats/min). Sixteen patients had perfusion defects after dipyridamole by SPECT, which underwent partial or total filling-in. Fourteen of these patients (87.5%) had either a new abnormality or further deterioration of a preexisting wall motion abnormality by 2-dimensional echocardiography, and thus were considered to have developed transient ischemia during dipyridamole administration. Ten of 11 patients (91%) with normal perfusion or fixed defects by SPECT had no further deterioration in wall motion after oral dipyridamole, and were thus considered to have no evidence of myocardial ischemia. In conclusion, most patients with transient thallium-201 defects after dipyridamole develop transient worsening of resting wall motion by 2-dimensional echocardiography, suggestive of true myocardial ischemia. Because myocardial oxygen demand, as indicated by the heart rate-blood pressure product, did not change significantly, the mechanism of myocardial ischemia in these patients is likely to be diminished regional blood flow related to a subendocardial steal induced by dipyridamole.

  4. Thallium-201 single photon emission computed tomography (SPECT) in patients with Duchenne's progressive muscular dystrophy. A histopathologic correlation study

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    Nishimura, Toru; Yanagisawa, Atsuo; Sakata, Konomi; Shimoyama, Katsuya; Yoshino, Hideaki; Ishikawa, Kyozo [Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine; Sakata, Hitomi; Ishihara, Tadayuki

    2001-02-01

    The pathomorphologic mechanism responsible for abnormal perfusion imaging during thallium-201 myocardial single photon emission computed tomography ({sup 201}Tl-SPECT) in patients with Duchenne's progressive muscular dystrophy (DMD) was investigated. Hearts from 7 patients with DMD were evaluated histopathologically at autopsy and the results correlated with findings on initial and delayed resting {sup 201}Tl-SPECT images. The location of segments with perfusion defects correlated with the histopathologically abnormal segments in the hearts. Both the extent and degree of myocardial fibrosis were severe, especially in the posterolateral segment of the left ventricle. Severe transmural fibrosis and severe fatty infiltration were common in segments with perfusion defects. In areas of redistribution, the degree of fibrosis appeared to be greater than in areas of normal perfusion; and intermuscular edema was prominent. Thus, the degree and extent of perfusion defects detected by {sup 201}Tl-SPECT were compatible with the histopathology. The presence of the redistribution phenomenon may indicate ongoing fibrosis. Initial and delayed resting {sup 201}Tl-SPECT images can predict the site and progress of myocardial degeneration in patients with DMD. (author)

  5. Imaging of brain tumors in AIDS patients by means of dual-isotope thallium-201 and technetium-99m sestamibi single-photon emission tomography

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    De La Pena, R.C.; Ketonen, L.; Villanueva-Meyer, J. [Dept. of Radiology, Univ. of Texas, Galveston (United States)

    1998-10-01

    Our aim was to evaluate the use of dual-isotope thallium-201 (Tl) and technetium-99m sestamibi (sestamibi) simultaneous acquisition in brain single-photon emission tomography (SPET) for the differentiation between brain lymphoma and benign central nervous system (CNS) lesions in AIDS patients. Thirty-six consecutive patients with enhancing mass lesions on magnetic resonance (MR) imaging were included in the study. SPET of the brain was performed to obtain simultaneous Tl and sestamibi images. Regions-of-interest were drawn around the lesion and on the contralateral side to calculate uptake ratios. The final diagnosis was reached by pathologic findings in 17 patients and clinical and/or MR follow-up in 19 patients. Of the 36 patients, 11 had brain lymphoma, 1 glioblastoma multiforme, 15 toxoplasmosis and 9 other benign CNS lesions. Correlation between SPET and the final diagnosis revealed in 10 true-positive, 23 true-negative, 1 false-positive and 2 false-negative studies. All patients with toxoplasmosis had negative scans. A patient with a purulent infection had positive scans. Tl and sestamibi scans were concordant in every lesion. The same lesions that took up Tl were also visualized with sestamibi. However, sestamibi scans showed higher lesion-to-normal tissue uptake ratios (3.7{+-}1.8) compared with those of Tl (2.3{+-}0.8, P<0.002). Simultaneous acquisition of Tl and sestamibi can help differentiate CNS lymphoma from benign brain lesions in AIDS patients. (orig.) With 2 figs., 2 tabs., 34 refs.

  6. Iodine-123 phenylpentadecanoic acid and single photon emission computed tomography in identifying left ventricular regional metabolic abnormalities in patients with coronary heart disease: comparison with thallium-201 myocardial tomography.

    Science.gov (United States)

    Hansen, C L; Corbett, J R; Pippin, J J; Jansen, D E; Kulkarni, P V; Ugolini, V; Henderson, E; Akers, M; Buja, L M; Parkey, R W

    1988-07-01

    Iodine-123 phenylpentadecanoic acid (IPPA) is a synthetic long chain fatty acid with myocardial kinetics similar to palmitate. Two hypotheses were tested in this study. The first hypothesis was that IPPA imaging with single photon emission computed tomography (SPECT) is useful in the identification of patients with coronary artery disease. Fourteen normal volunteers (aged 27 +/- 2 years) and 33 patients (aged 54 +/- 11 years) with stable symptomatic coronary artery disease and at least one major coronary artery with luminal diameter narrowing greater than or equal to 70% were studied with symptom-limited maximal exercise testing. The IPPA (6 to 8 mCi) was injected 1 min before the termination of exercise, and tomographic imaging was performed beginning at 9 min and repeated at 40 min after the injection of IPPA. Nine of the normal volunteers and 13 of the patients had a second examination performed at rest on another day. Using the limits of normal as 2 SD from the normal mean values, 27 of the 33 patients with coronary artery disease demonstrated abnormalities in either the initial distribution or the clearance of IPPA, or both. Nineteen of the 33 patients had a maximal variation of activity distribution of greater than or equal to 25% on the 9 min IPPA images. Twenty-two of the 33 patients had a maximal variation in IPPA washout greater than 17% and 17 had a washout rate less than or equal to 2%. There was good agreement between the location of significant coronary artery stenoses and abnormalities in the initial distribution and clearance of IPPA. The second hypothesis tested was that IPPA imaging is as or more sensitive and, therefore, complementary to thallium-201 imaging in the identification of exercise-induced ischemia in patients. Twenty-five of the 33 patients underwent both thallium-201 and IPPA tomographic imaging after symptom-limited maximal exercise testing. The amount of exercise performed by each patient during both studies was similar. Twenty

  7. Significance of exercise-induced ST segment depression in patients with myocardial infarction involving the left circumflex artery. Evaluation by exercise thallium-201 myocardial single photon emission computed tomography

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    Koitabashi, Norimichi; Toyama, Takuji; Hoshizaki, Hiroshi [Gunma Prefectural Cardiovascular Center, Maebashi (Japan)] [and others

    2000-04-01

    The significance of exercise-induced ST segment depression in patients with left circumflex artery involvement was investigated by comparing exercise electrocardiography with exercise thallium-201 single photon emission computed tomography (Tl-SPECT) and the wall motion estimated by left ventriculography. Tl-SPECT and exercise electrocardiography were simultaneously performed in 51 patients with left circumflex artery involvement (angina pectoris 30, myocardial infarction 21). In patients with myocardial infarction, exercise-induced ST depression was frequently found in the V{sub 2}, V{sub 3} and V{sub 4} leads. In patients with angina pectoris, ST depression was frequently found in the II, III, aV{sub F}, V{sub 5} and V{sub 6} leads. There was no obvious difference in the leads of ST depression in patients with myocardial infarction with ischemia and without ischemia on Tl-SPECT images. In patients with myocardial infarction, the lateral wall motion of the infarcted area evaluated by left ventriculography was more significantly impaired in the patients with ST depression than without ST depression (p<0.01). Exercise-induced ST depression in the precordial leads possibly reflects wall motion abnormality rather than ischemia in the lateral infarcted myocardium. (author)

  8. Evaluation of myocardial flow reserve using pharmacological stress thallium-201 single-photon emission computed tomography: is there a difference between total arterial off-pump coronary artery bypass grafting and conventional coronary artery bypass grafting?

    Science.gov (United States)

    Lee, Jae Won; Ryu, Sang Wan; Song, Hyun; Kim, Kyung Sun; Yang, Yu Jung; Moon, Dae Hyeuk

    2004-01-01

    The advantage of total arterial off-pump coronary bypass grafting (OPCAB) over conventional onpump coronary artery bypass grafting with 1 internal thoracic artery and veins (CCAB) in terms of myocardial flow reserve has not been studied. We studied these procedures using thallium- 201 perfusion single-photon emission computed tomography (Tl-201 perfusion SPECT). Between 1997 and 2001, 152 patients were recruited from our database (OPCAB, n = 100; CCAB, n = 52). All patients underwent pharmacological stress Tl-201 perfusion SPECT 3 to 12 months after bypass surgery. Myocardial perfusion was analyzed semiquantitatively with a 5-point scoring system in a 20-segment model (0, normal, to 4, absence of uptake). Summed stress (SSS), rest (SRS), and difference score (SDS) of the entire myocardium as well as average scores (ASS, ARS, ADS) of individual walls (anterior, septal, lateral, and inferior) were compared by Student t test as well as by repeated-measures analysis of variance with Bonferroni correction. The SSS, SRS, and SDS of OPCAB versus those of CCAB were 6.86 +/- 0.72 versus 7.17 +/- 0.92, 3.95 +/- 0.57 versus 3.75 +/- 0.73, and 2.91 +/- 0.47 versus 3.42 +/- 0.74 (P > .05). However, the lateral wall showed lower scores in OPCAB (ASS, 0.18 versus 0.41, P = .015; ARS, 0.12 versus 0.20, P = .168; ADS, 0.06 versus 0.21, P = .031). The septal wall had higher scores in OPCAB (ASS, 0.33 versus 0.12, P = .003; ARS, 0.18 versus 0.07, P = .037; ADS, 0.14 versus 0.04, P = .030). The anterior and inferior walls were not different between the 2 groups. OPCAB led to results similar to those of CCAB. The better results in the lateral wall have been the effect of grafting radial artery rather than vein. The similarity in myocardial reserve in the inferior wall between the 2 groups needs further study. There was no deleterious effect of off-pump as opposed to on-pump CAB.

  9. Effect of long-term cholesterol-lowering treatment with HMG-CoA reductase inhibitor (Simvastatin) of myocardial perfusion evaluated by thallium-201 single photon emission computed tomography

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    Hosokawa, Ryohei; Nohara, Ryuji; Linxue, Li; Sasayama, Shigetake [Kyoto Univ. (Japan). Graduate School of Medicine; Tamaki, Shunichi; Hashimoto, Tetsuo; Tanaka, Masahiro; Miki, Shinji

    2000-03-01

    Fifteen patients with either angina pectoris or old myocardial infarction, who had positive {sup 201}Tl single photon emission computed tomography (SPECT) imaging and coronary sclerosis of more than 50%, were treated with an HMG-CoA reductase inhibitor (simvastatin) for more than 1 year. They were compared with an untreated control group (n=25). Total cholesterol decreased 22% and high-density lipoprotein (HDL) increased 9% with simvastatin; both changes were significantly different from those in controls. Long-term simvastatin induced improvement of myocardial perfusion on {sup 201}Tl SPECT images both during exercise and at rest, which was also significantly different from controls. In addition, the improvement of myocardial perfusion on {sup 201}Tl SPECT images was clearly related to the improvements in cholesterol values, especially nonHDL cholesterol. Thus, the greater the decrease in nonHDL cholesterol, the greater the improvement in myocardial perfusion at rest or during exercise with long-term treatment using an HMG-CoA reductase inhibitor. These findings indicate that the improvements in cholesterol values caused by HMG-CoA reductase inhibitor therapy are related to improvements of myocardial perfusion seen on {sup 201}Tl SPECT images. (author)

  10. Dual myocardial single photon emission computed tomography (SPECT) using thallium-201 and I-123-{beta}-methyl-i-pentadecanoic acid in patients with Duchenne's progressive muscular dystrophy

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    Shimoyama, Katsuya [Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine

    1999-10-01

    Dual single photon emission computed tomography (SPECT) was performed in 31 patients with Duchenne's progressive muscular dystrophy (DMD) using {sup 123}I-{beta}-methyl pentadecanoic acid (BMIPP) for myocardial fatty acid metabolism and {sup 201}thallium (Tl)-chloride for myocardial perfusion. The left ventricle was divided into 9 segments, and accumulation of the radiotracers was assessed visually for each segment to calculate defect score for each tracer. There was some degree of decrease in myocardial accumulation of both tracers in all DMD patients. Reduced accumulation was most common at the apex (BMIPP: 67%, Tl: 63%), followed by the posterior wall, lateral wall, and anterior wall. On the other hand, reduced accumulation was less common at the septum. BMIPP showed a higher accumulation than Tl in all segments but the septum. When BMIPP defect score was larger than Tl defect score, BMIPP defect score tended to increase during 4 years follow-up (p<0.042). However, when Tl defect score was larger than BMIPP defect score, an increase in Tl defect score was slight. A significant negative correlation was found between the sum of the BMIPP and Tl defect scores and the left ventricular ejection fraction (LVEF) (r=0.66, p<0.0001). According to the histo-pathological study of two autopsied hearts, severe myocardial fibrosis was seen in segments with fixed perfusion defect. In addition, the mismatched segments of BMIPP defect score > Tl defect score revealed a slight fibrosis or normal myocardium. It can be concluded that the dual SPECT myocardial scintigraphy using BMIPP and Tl provides accurate information about disease progression of the heart in patients with DMD by detecting abnormalities of the myocardial metabolism of each substance, thereby enabling the assessment of left ventricular function. (author)

  11. Repeat thallium-201 SPECT in cerebral lymphoma.

    Science.gov (United States)

    Borggreve, F; Dierckx, R A; Crols, R; Mathijs, R; Appel, B; Vandevivere, J; Mariën, P; Martin, J J; De Deyn, P P

    1993-01-01

    The authors report on the contribution of Thallium-201 brain SPECT in the diagnosis and follow-up of a non-immunosuppressed patient, presenting with primary cerebral lymphoma. The tumoral process was at first not diagnosed on CT-scan, but Thallium-201 SPECT suggested a tumoral invasion. During corticosteroid treatment the tumor volume on CT-scan decreased, while on Thallium-201 SPECT there was an enhancement of the accumulation and an increasing tumor to non-tumor ratio. These scintigraphical findings more closely reflected the clinical course and the postmortem results.

  12. Thallium-201 scintigraphy in unstable angina pectoris

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    Wackers, F.J.T.; Lie, K.I.; Liem, K.L.; Sokole, E.B.; Samson, G.; Van Der Schoot, J.B.; Durrer, D.

    1978-04-01

    Thallium-201 scintigraphy was performed during the pain free period in 98 patients with unstable angina. Scintiscans were positive in 39 patients, questionable in 27 patients and normal in 32 patients. Eighty-one patients responded favorably to treatment (group I). Seventeen patients had complicated courses (group II) and despite maximal treatment with propranolol either developed infarction (six patients) or continued to have angina necessitating coronary surgery (11 patients). In group I during the pain free period 26 of 81 patients had positive thallium-201 scans, whereas 20 patients had an abnormal ECG at that time; during angina 18 patients had transient ECG changes. In group II during the pain free period 13 of 17 patients had positive scans, whereas two patients had abnormal ECG at that time; during angina 12 patients showed transient ECG changes. The sensitivity to recognize group II was 76% for thallium-201 scintigraphy, 11% for ECG during the pain free period; 70% for ECG during angina; 94% for the combination of either positive scans or abnormal ECG. Thus, positive thallium-201 scans occur in patients with unstable angina, positive scans can be obtained during the pain free period, thallium-201 scans are more frequently positive in patients with complicated course.

  13. New CZT cardiac cameras and myocardial perfusion imaging with thallium 201; Nouvelles cameras cardiaques a semi-conducteur cadmium -zinc- telluride (CZT) et scintigraphies myocardiques au thallium 201

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    Songy, B. [Service de medecine et imagerie nucleaire, centre cardiologique du Nord (CCN), 93 - Saint-Denis (France)

    2010-08-15

    Myocardial perfusion imaging is widely used for management of coronary artery disease. However, it suffers from technical limitations. New cardiac cameras using CZT detectors are now available and increase spatial (x2) and energy (x2) resolutions and photons sensitivity (x5). We describe here the General Electric Discovery NM 530c new camera and summarize the validation studies with technetium agents and with thallium 201, protocols to reduce doses, ultrafast protocols and perspectives offered with this new technology. (author)

  14. Evaluation of myocardial damage in Duchenne's muscular dystrophy with thallium-201 myocardial SPECT

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    Tamura, Takuhisa; Shibuya, Noritoshi (Kawatana National Hospital, Nagasaki (Japan)); Hashiba, Kunitake; Oku, Yasuhiko; Mori, Hideki; Yano, Katsusuke

    1993-01-01

    Myocardial damage and cardiopulmonary functions in patients with Duchenne's muscular dystrophy (DMD) were assessed using thallium-201 myocardial single-photon emission computed tomography (SPECT) and technetium-99m multigated radionuclide angiography. Twenty-five patients with DMD were divided into 4 groups according to percent of perfusion defect (%PD) calculated by the bull's-eye method and age. PD was detected in 24 (96.0%) of 25 patients with DMD, and it spread from the left ventricular lateral wall to the anterior wall and/or interventricular septum. PD was detected even in a 6-year-old DMD boy. Patients in Group I (%PD[>=]10% and age<15 years old) were shown to have a higher risk of left-sided heart failure without respiratory failure. Patients in Group II (%PD[>=]10 and age[>=]15) showed decreased pulmonary function and worsened arterial blood gas values as compared with Group IV (%PD<10 and age[>=]15). There was no significant difference in cardiac function among the 4 groups. It is postulated that myocardial damage in Group II patients is dependent primarily on a deficiency of dystrophin and on chronic respiratory failure, and that some of them are at risk of cardiopulmonary failure. It is concluded that myocardial SPECT is useful for the early diagnosis of myocardial damage and evaluation of cardiopulmonary function in DMD patients. (author).

  15. A comparison of the clinical relevance of thallium201 and ...

    African Journals Online (AJOL)

    Thallium-201 is at present the radiotracer of choice for the clinical evaluation of myocardial blood flow. Although different technetium-99m-isonitrile agents have been synthesised recently, only 99mTc-melhoxyisobutyl-isonitrile (99mTc_MIBI) has proved to hold promise for clinical implementation. The myocardial distribution ...

  16. Reduced left ventricular cavitary activity ("black hole sign") in thallium-201 SPECT perfusion images of anteroapical transmural myocardial infarction.

    Science.gov (United States)

    Civelek, A C; Shafique, I; Brinker, J A; Durski, K; Weiss, J L; Links, J M; Natarajan, T K; Ozguven, M A; Wagner, H N

    1991-11-01

    Apparently reduced left ventricular (LV) cavitary thallium activity in both planar and tomographic perfusion images has been previously observed by these and other investigators. With single-photon emission computerized tomography, we have clinically noted that this "black hole sign" was associated with an aneurysm in the setting of a transmural anterior or anteroapical perfusion defect. We have now prospectively studied the etiology and predictive value of this sign in 84 consecutive patients with an anterior, anteroapical transmural perfusion defect. Of the 84 patients, 49 had both LV aneurysm (confirmed by contrast ventriculography, echocardiography or gated blood pool studies) and a black hole sign. Only 1 patient with an aneurysm did not have the black hole sign, and 2 without aneurysm did. Thus, it is concluded that this sign is highly accurate in diagnosing LV aneurysm. Because thallium-201 single-photon emission computerized tomography imaging is often performed as one of the first diagnostic tests soon after myocardial infarction, this has important clinical management implications.

  17. MRI and thallium-201 SPECT in the prediction of survival in glioma

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    Vos, Maaike J. [VU University Medical Center, Department of Neurology, Amsterdam (Netherlands); Medical Center Haaglanden, Department of Neurology, PO Box 432, The Hague (Netherlands); Berkhof, Johannes [VU University Medical Center, Department of Epidemiology and Biostatistics, Amsterdam (Netherlands); Hoekstra, Otto S. [VU University Medical Center, Department of Nuclear Medicine and PET Research, Amsterdam (Netherlands); Bosma, Ingeborg; Sizoo, Eefje M.; Heimans, Jan J.; Reijneveld, Jaap C.; Postma, Tjeerd J. [VU University Medical Center, Department of Neurology, Amsterdam (Netherlands); Sanchez, Esther [VU University Medical Center, Department of Radiology, Amsterdam (Netherlands); Lagerwaard, Frank J. [VU University Medical Center, Department of Radiation Oncology, Amsterdam (Netherlands); Buter, Jan [VU University Medical Center, Department of Medical Oncology, Amsterdam (Netherlands); Noske, David P. [VU University Medical Center, Department of Neurosurgery and Neuro-Oncology Research Group, Amsterdam (Netherlands)

    2012-06-15

    This paper aims to study the value of MRI and Thallium 201 ({sup 201}Tl) single-photon emission computed tomography (SPECT) in the prediction of overall survival (OS) in glioma patients treated with temozolomide (TMZ) and to evaluate timing of radiological follow-up. We included patients treated with TMZ chemoradiotherapy for newly diagnosed glioblastoma multiforme (GBM) and with TMZ for recurrent glioma. MRIs and {sup 201}Tl SPECTs were obtained at regular intervals. The value of both imaging modalities in predicting OS was examined using Cox regression analyses. Altogether, 138 MRIs and 113 {sup 201}Tl SPECTs in 46 patients were performed. Both imaging modalities were strongly related to OS (P {<=} 0.02). In newly diagnosed GBM patients, the last follow-up MRI (i.e., after six adjuvant TMZ courses) and SPECT (i.e., after three adjuvant TMZ courses) were the strongest predictors of OS (P = 0.01). In recurrent glioma patients, baseline measurements appeared to be the most predictive of OS (P < 0.01). The addition of one imaging modality to the other did not contribute to the prediction of OS. Both MRI and {sup 201}Tl SPECT are valuable in the prediction of OS. It is adequate to restrict to one of both modalities in the radiological follow-up during treatment. In the primary GBM setting, MRI after six adjuvant TMZ courses contributes significantly to the prediction of survival. In the recurrent glioma setting, baseline MRI appears to be a powerful predictor of survival, whereas follow-up MRIs during TMZ seem to be of little additional value. (orig.)

  18. Quantitative evaluation of thallium-201 myocardial scintigram in coronary artery diseases

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    Mikada, Ken-etsu (Akita Univ. (Japan). School of Medicine)

    1992-11-01

    Quantitative indices from circumferential profile curves of thallium-201 ([sup 201]Tl) myocardial scintigram were evaluated for diagnostic utility in coronary artery diseases (CAD). Myocardial [sup 201]Tl scintigrams with single photon emission computed tomography (SPECT) were obtained 5 minutes (early) and 4 hours (delayed) after exercise in 20 normal subjects and 66 cases of CAD, of which 20 were angina pectoris without myocardial infarction (AP), 14 were subendocardial infarction (non-QMI) and 32 were Q-wave infarction (QMI). Tl counts, %Tl uptake and washout ratio (WR) were measured in 81 segments (9 apical segments of the slice from the longitudinal axis and all 72 segments of two slices from the short axis). A mean early defect (MED), a mean delayed defect (MDD), a mean delta washout rate (MDR), and a [Sigma] delayed defect ([Sigma]DD) were calculated from the areas which were below the two standard deviations of the mean %Tl uptake in normal subjects. A mean filling-in (MFI) was calculated from the difference of the %Tl uptake between early and delayed curves in each patient. In patients with CAD, the MED and MFI were higher, but MDW was lower with a more severe coronary stenosis, indicating that these indices were useful to detect myocardial hypo-perfuion. In severely stenotic regions, the MDD was higher in QMI than in AP and non-QMI, indicating that the ratio of infarct to the myocardium in the region was higher in QMI. In QMI, [Sigma]DD correlated well (r=0.723) with Total Wall Motion Scores with two-dimentional echocardiography which was directly related with infarct size. Further, MED, MFI and MDW were improved after aortocoronary bypass only in patients with patent graft. It is concluded that this quantitative evaluation with [sup 201]Tl-SPECT can provide an objective and quantitative estimate of regional myocardial ischemia and infarct. (author).

  19. Usefulness of thallium-201 SPECT in the evaluation of tumor natures in intracranial meningiomas

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    Takeda, Tetsuji; Nakano, Takahiro; Asano, Kenichiroh; Shimamura, Norihito; Ohkuma, Hiroki [Hirosaki University Graduate School of Medicine, Department of Neurosurgery, Hirosaki (Japan)

    2011-11-15

    Although intracranial meningiomas are regarded as benign tumors, some of them behave clinically as malignant tumors. Past reports suggest that MIB 1 and vascular endothelial growth factor (VEGF) in postoperative tumor specimens correlate with the aggressive nature of tumors, but preoperative prediction of such a nature is more useful for therapeutic planning for the tumor. The purpose of this study was to assess the usefulness of preoperative thallium-201 chloride single-photon emission computed tomography (Tl SPECT) to evaluate biological behavior in intracranial meningiomas. Tl SPECT was performed on 39 patients with intracranial meningioma and Tl uptake indices were calculated. The difference in the Tl uptake index between atypical meningiomas and other pathological types of meningioma was evaluated. Moreover, correlation of Tl uptake indices with the MIB1 labeling index was estimated. Tl uptake indices were also compared between VEGF strongly positive and weakly positive meningiomas. The delayed index of atypical meningioma was significantly higher than that of the other pathological types (p = 0.036). Significant correlation was found between the Tl uptake index in the delayed image and MIB1 labeling index (p < 0.0001, R{sup 2} = 0.36). Moreover, VEGF strongly positive meningiomas exhibited a significantly higher Tl uptake index compared to VEGF weakly positive meningiomas in both the early image and the delayed image (p = 0.029, 0.023, respectively). Tl uptake index may be a possible preoperative surrogate marker of MIB1 and VEGF that is useful in detecting aggressive natures in intracranial meningiomas. (orig.)

  20. Thallium-201 is comparable to technetium-99m-sestamibi for estimating cardiac function in patients with abnormal myocardial perfusion imaging

    Directory of Open Access Journals (Sweden)

    Ming-Che Wu

    2015-11-01

    Full Text Available We analyzed the left-ventricular functional data obtained by cardiac-gated single-photon emission computed tomography myocardial perfusion imaging (MPI with thallium-201 (Tl-201 and technetium-99m-sestamibi (MIBI protocols in different groups of patients, and compared the data between Tl-201 and MIBI. Two hundred and seventy-two patients undergoing dipyridamole stress/redistribution Tl-201 MPI and 563 patients undergoing 1-day rest/dipyridamole stress MIBI MPI were included. Higher mean stress ejection fraction (EF, rest EF, and change in EF (ΔEF were noticed in the normal MPI groups by both Tl-201 and MIBI protocols. Higher mean EF was observed in the females with normal MPI results despite their higher mean age. Comparisons between the Tl-201 and MIBI groups suggested a significant difference in all functional parameters, except for the rest end diastolic volume/end systolic volume and ΔEF between groups with negative MPI results. For the positive MPI groups, there was no significant difference in all parameters, except for the change in end diastolic volume and change in end systolic volume after stress between both protocols. The Tl-201 provides comparable left-ventricular functional data to MIBI cardiac-gated single-photon emission computed tomography in patients with positive MPI results, and may therefore be undertaken routinely for incremental functional information that is especially valuable to this patient group.

  1. Evaluation of muscular lesions in connective tissue diseases: thallium 201 muscular scans

    Energy Technology Data Exchange (ETDEWEB)

    Guillet, G.; Guillet, J.; Sanciaume, C.; Maleville, J.; Geniaux, M.; Morin, P.

    1988-04-01

    We performed thallium 201 muscle scans to assess muscular involvement in 40 patients with different connective tissue diseases (7 with dermatomyositis, 7 with systemic lupus erythematosus, 12 with progressive systemic scleroderma, 2 with calcinosis, Raynaud's phenomenon, esophageal involvement, sclerodactyly, and telangiectasia (CREST) syndrome, 3 with monomelic scleroderma, 6 with morphea, and 3 with Raynaud's disease). Only 12 of these patients complained of fatigability and/or myalgia. Electromyography was performed and serum levels of muscle enzymes were measured in all patients. Comparison of thallium 201 exercise recording with the other tests revealed that scan sensitivity is greater than electromyographic and serum muscle enzymes levels. Thallium 201 scans showed abnormal findings in 32 patients and revealed subclinical lesions in 18 patients, while electromyography findings were abnormal in 25 of these 32 patients. Serum enzyme levels were raised in only 8 patients. Thallium 201 scanning proved to be a useful guide for modifying therapy when laboratory data were conflicting. It was useful to evaluate treatment efficacy. Because our data indicate a 100% positive predictive value, we believe that thallium 201 scanning should be advised for severe systemic connective tissue diseases with discordant test results.

  2. Exercise-induced thallium-201 myocardial perfusion defects in angina pectoris without significant coronary artery stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Nakazato, Masayasu; Maruoka, Yuji; Sunagawa, Osahiko; Kinjo, Kunihiko; Tomori, Masayuki; Fukiyama, Koshiro (Ryukyu Univ., Nishihara, Okinawa (Japan). School of Medicine)

    1990-01-01

    We performed exercise thallium-201 myocardial scintigraphy in 32 patients with angina pectoris to study the incidence of perfusion defects, who had no significant organic stenosis on coronary angiography. None of them had myocardial infarction or cardiomyopathy. Thallium-201 myocardial scintigraphy and 12-lead ECG recording were performed during supine bicycle ergometer exercise. Perfusion defects in thallium-201 scintigrams in SPECT images were assessed during visual analysis by two observers. In the coronary angiograms obtained during intravenous infusion of nitroglycerin, the luminal diameter of 75% stenosis or less in the AHA classification was regarded as an insignificant organic stenosis. Myocardial perfusion defects in the thallium-201 scintigrams were detected in eight (25%) of the 32 patients. Six of these eight patients had variant angina documented during spontaneous attacks with ST elevations in standard 12-lead ECGs. Perfusion defects were demonstrated at the inferior or infero-posterior regions in six patients, one of whom had concomitant anteroseptal defect. The defects were not always accompanied by chest pain. All but one patient demonstrating inferior or inferoposterior defects showed ST depression in leads II, III and aV{sub F} on their ECGs, corresponding to inferior wall ischemia. The exception was a case with right bundle branch block. Thus, 25% of the patients with angina pectoris, who had no evidence of significant organic stenosis on their coronary angiograms, exhibited exercise-induced perfusion defects in their thallium-201 scintigrams. Coronary spasms might have caused myocardial ischemia in these patients. (author).

  3. Early and delayed thallium-201 scintigraphy in thyroid nodules: the relationship between early thallium-201 uptake and perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Derebek, E. [Dept. of Nuclear Medicine, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Biberoglu, S. [Dept. of Internal Medicine, Div. of Endocrinology, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Kut, O. [Dept. of Nuclear Medicine, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Yesil, S. [Dept. of Internal Medicine, Div. of Endocrinology, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Saydam, S. [Dept. of Surgery, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Yilmaz, M. [Dept. of Nuclear Medicine, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Yenici, O. [Dept. of Nuclear Medicine, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Igci, E. [Dept. of Radiology, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Gokce, O. [Dept. of Surgery, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Canda, S. [Dept. of Pathology, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Bueyuekgebiz, A. [Dept. of Pediatrics, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Dogan, A.S. [Dept. of Nuclear Medicine, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Durak, H. [Dept. of Nuclear Medicine, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey)

    1996-05-01

    Seventy-six patients with tyroid nodules were studied. Initially, 75 MBq of thallium-201 was injected. The thyroid gland was imaged 15 min (early) and 3 h (delayed) after the injection. Thereafter, 185 MBq technetium-99m pertechnetate was injected. Immediately after the injection, a 1-min perfusion image was acquired, followed by an image at 20 min. Increased early and delayed {sup 201}Tl uptake compared with the contralateral thyroid tissue was adopted as the criterion for malignancy. Sensitivity, specificity and negative predictive values were found to be 85%, 64% and 78%, respectively, in operated patients, but these values were 86%, 87% and 95%, respectively, in the whole group, including patients followed with fine-needle aspiration biopsy. With the purpose of investigating the relationship between perfusion and early {sup 201}Tl uptake, bot perfusion and early images were graded comparing nodular activity with contralateral thyroid activity. There was a poor correlation between perfusion and {sup 201}Tl uptake. The correlation was even worse in hyperactive nodules. It is concluded that early and delayed {sup 201}Tl imaging should not be used in the differential diagnosis of cold nodules and that early {sup 201}Tl uptake seems to be more closely related to factors other than perfusion. (orig.)

  4. Combined thallium-201 and dynamic iodine-123 iodophenylpentadecanoic acid single-photon emission computed tomography in patients after acute myocardial infarction with effective reperfusion.

    Science.gov (United States)

    Richter, W S; Beckmann, S; Cordes, M; Schuppenhauer, T; Schartl, M; Munz, D L

    2000-12-01

    Considerable derangements of energy metabolism are to be expected during ischemia and reperfusion. In ischemic myocardium, the oxidative degradation of carbohydrates is shifted toward the anaerobic production of lactate and the oxidation of fatty acids is suppressed. The aim of this study was to examine the uptake and metabolism of iodine-123 (123I) iodophenylpentadecanoic acid (IPPA) in stunned myocardium. In 15 patients, SPECT with 201Tl and 123I IPPA as well as echocardiography with low-dose dobutamine stimulation were performed 12 +/- 5 days after myocardial infarction with reperfusion. Follow-up echocardiography was carried out 24 +/- 8 days later for documentation of functional improvement. Uptake of 201Tl and 123I IPPA were obtained in five left ventricular segments, and dynamic SPECT imaging was used for calculation of the fast and the slow components of the biexponential myocardial 123I IPPA clearance. Wall motion improved in 14 of 26 dysfunctional segments (54%). Stunned segments were characterized by a reduced 123I IPPA extraction, a shorter half-life of the fast, and a longer half-life of the slow clearance component. All parameters of the combined 201Tl/123I IPPA study predicted functional recovery with similar accuracies (area under the receiver operator characteristic curves between 0.68 and 0.76; p = NS). Analysis of 201Tl uptake alone could not predict functional recovery in this study. Stunned myocardium is characterized by a disturbance of fatty acid metabolism. For prediction of functional improvement, 123I IPPA imaging added significant diagnostic information.

  5. Left ventricular dilatation and pulmonary thallium uptake after single-photon emission computer tomography using thallium-201 during adenosine-induced coronary hyperemia

    Energy Technology Data Exchange (ETDEWEB)

    Iskandrian, A.S.; Heo, J.; Nguyen, T.; Lyons, E.; Paugh, E. (Philadelphia Heart Institute, PA (USA))

    1990-10-01

    This study examined the implications of left ventricular (LV) dilatation and increased pulmonary thallium uptake during adenosine-induced coronary hyperemia. The lung-to-heart thallium ratio in the initial images was significantly higher in patients with coronary artery disease (CAD) than normal subjects; 0.48 +/- 0.16 in 3-vessel disease (n = 16), 0.43 +/- 0.10 in 2-vessel disease (n = 20), 0.43 +/- 0.08 in 1-vessel disease (n = 16) and 0.36 +/- 0.05 in normal subjects (n = 7) (p less than 0.001, 0.09 and 0.06, respectively). There was a significant correlation between the severity and the extent of the perfusion abnormality (determined from the polar maps) and the lung-to-heart thallium ratio (r = 0.51 and 0.52, respectively, p less than 0.0002). There was also a significant correlation between lung thallium washout and lung-to-heart thallium ratio (r = 0.42, p = 0.0009) and peak heart rate (r = -0.49, p less than 0.0001). The LV dilatation was mostly due to an increase in cavity dimension (30% increase) and to a lesser extent (6% increase) due to increase in LV size. (The cavity dimensions were measured from the short-axis slices at the midventricular level in the initial and delayed images). The dilation was seen in patients with CAD but not in the normal subjects. These changes correlated with the extent and severity of the thallium perfusion abnormality. Thus, adenosine-induced coronary hyperemia may cause LV dilation and increased lung thallium uptake on the basis of subendocardial ischemia.

  6. A new method of detecting subendocardial ischemia in patients with aortic valvular stenosis without coronary artery disease using thallium-201 single photon emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Umamoto, Ikuo; Sugihara, Hiroki; Harada, Yoshiaki (Kyoto Prefectural Univ. of Medicine (Japan)) (and others)

    1993-02-01

    The purpose of this study was to detect myocardial ischemia in aortic valvular stenosis (AVS) without coronary artery disease by using exercise Tl-201 SPECT. The subjects were 18 AVS patients. Twenty other patients were served as controls. Transient 'left ventricular subendocardial dilation and decreased wall thickness', obtained on early SPECT images, were quantitatively determined by transient dilation index (TDI). Washout rates (WR) were calculated from overlapping early and delayed images to obtain WR map. According to TDI, 18 AVS patients were classified as having TDI[<=]1.11 (Group A, n=9) and TDI>1.11 (Group B, n=9). WR map in Group B presented the direction from the pericardial toward the endocardial side, revealing a pattern of decreased WR and a decreased coronary flow reserve on the endocardial side. Both pressure gradient between the aorta and left ventricle and left ventricular wall thickness were significantly greater in Group B than Group A. In 3 patients in Group B, TDI returned to normal and WR map became homogeneous after aortic valve replacement. In addition, fibrosis was noted in the endocardial site on biopsy. In AVS associated with great pressure gradient, endocardial ischemia may occur on exercise, resulting from a decreased coronary flow reserve, and a decreased compliance due to fibrosis and hypertrophy. Exercise Tl-201 myocardial SPECT is capable of detecting distribution patterns of subendocardial ischemia and coronary flow reserve in AVS. (N.K.).

  7. Genotoxic and mutagenic effects of the diagnostic use of thallium-201 in nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Kelsey, K.T. (Harvard School of Public Health, Boston, MA (United States)); Donohoe, K.J. (Beth Israel Hospital, Boston, MA (United States). Div. of Nuclear Medicine); Baxter, Barbara; Memisoglu, Asli; Little, J.B.; Caggana, Michele; Liber, H.L. (Harvard School of Public Health, Boston, MA (United States))

    1991-07-01

    In order to investigate possible mutagenetic effects of in vivo exposure to low levels of ionizing radiation used in nuclear medicine, the authors examined hypoxanthine guanine phosphoribosyl transferase (hprt) mutant fraction (MF) and chromosome aberration (CA) frequency in 24 nuclear medicine patients before and after injection of thallium-201. The mean MF of the thallium-201-exposed cohort was 5.2{+-}4.4 x 10{sup -6} before injection exposure. No significant difference in MF was observed 24 h later. In 11 patients who were studied on a 3rd occasion, 30 days after thallium-201 exposure, there was again no significant difference in post-exposure as compared with the pre-exposure MF. The frequency of CA in peripheral blood lymphocytes was not significantly different, comparing pre- and 24h to 1 month post-radionuclide exposure . Thus, thallium-201 exposure was not associated with significant elevations in MF or CA frequency in lymphocytes of exposed individuals. (author). 40 refs.; 3 tabs.

  8. Clinical features and applications of thallium-201. With reference to scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Tadashige

    1988-12-01

    Thallium-201 is not only used widely in myocardial imaging but also has a great potential in other various nuclear medicine imaging studies. This paper presents clinical features and applications of thallium-201, focusing on clinical trials with thallium-201 at the Shinshu University School of Medicine. Thallium-201 myocardial scintigraphy offers information on (1) ventricular position and morphology, (2) hypertrophy or dilatation of the left ventricle, (3) hypertrophy or dilatation of the right ventricle, (4) site and extent of myocardial ischemia and infarct, (5) myocardial blood flow, (6) pulmonary congestion or interstitial pulmonary edema, and (7) pericardial effusion. It can be used in the following evaluation or diagnosis: (1) acute or old myocardial infarction, (2) angina pectoris, (3) treatment strategy or prognosis of ischemic heart disease, (4) treatment strategy or observation of bypass graft or drug therapy, (5) hypertrophic or dilated idiopathic cardiomyopathy, (6) myocardial lesions induced by sarcoidosis, collagen disease, and neuro-muscular disease, (7) ventricular hypertrophy and pulmonary edema, and (9) pericarditis, pericardial effusion, and systolic pericarditis associated with underlying disease. The significance of tumor, liver, bone marrow scintigraphies is also referred to. (Namekawa, K) 69 refs.

  9. A comparison of the clinical relevance of thallium- 201 and ...

    African Journals Online (AJOL)

    1990-09-01

    Sep 1, 1990 ... group of 20 patients, who underwent both 201TI single photon emission computed tomography and 99mTc_MIBI study as well as coronary angiography. The sensitivity for predicting a lesion ranged from 25% to 88% in different areas of the heart and was comparable for the two radiophannaceuticals. The.

  10. Diagnostic value of thallium-201 myocardial perfusion IQ-SPECT without and with computed tomography-based attenuation correction to predict clinically significant and insignificant fractional flow reserve: A single-center prospective study.

    Science.gov (United States)

    Tanaka, Haruki; Takahashi, Teruyuki; Ohashi, Norihiko; Tanaka, Koichi; Okada, Takenori; Kihara, Yasuki

    2017-12-01

    The aim of this study was to clarify the predictive value of fractional flow reserve (FFR) determined by myocardial perfusion imaging (MPI) using thallium (Tl)-201 IQ-SPECT without and with computed tomography-based attenuation correction (CT-AC) for patients with stable coronary artery disease (CAD).We assessed 212 angiographically identified diseased vessels using adenosine-stress Tl-201 MPI-IQ-SPECT/CT in 84 consecutive, prospectively identified patients with stable CAD. We compared the FFR in 136 of the 212 diseased vessels using visual semiquantitative interpretations of corresponding territories on MPI-IQ-SPECT images without and with CT-AC.FFR inversely correlated most accurately with regional summed difference scores (rSDS) in images without and with CT-AC (r = -0.584 and r = -0.568, respectively, both P < .001). Receiver-operating characteristics analyses using rSDS revealed an optimal FFR cut-off of <0.80 without and with CT-AC. Although the diagnostic accuracy of FFR <0.80 did not significantly differ, FFR ≥0.82 was significantly more accurate with, than without CT-AC. Regions with rSDS ≥2 without or with CT-AC predicted FFR <0.80, and those with rSDS ≤1 without and with CT-AC predicted FFR ≥0.81, with 73% and 83% sensitivity, 84% and 67% specificity, and 79% and 75% accuracy, respectively.Although limited by the sample size and the single-center design, these findings showed that the IQ-SPECT system can predict FFR at an optimal cut-off of <0.80, and we propose a novel application of CT-AC to MPI-IQ-SPECT for predicting clinically significant and insignificant FFR even in nonobese patients. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

  11. Technetium-99m pyrophosphate/thallium-201 dual-isotope SPECT imaging predicts reperfusion injury in patients with acute myocardial infarction after reperfusion

    Energy Technology Data Exchange (ETDEWEB)

    Akutsu, Yasushi; Kaneko, Kyouichi; Kodama, Yusuke; Li, Hui-Ling; Nishimura, Hideki; Hamazaki, Yuji; Kobayashi, Youichi [Showa University School of Medicine, Division of Cardiology, Department of Medicine, Tokyo (Japan); Suyama, Jumpei; Shinozuka, Akira; Gokan, Takehiko [Showa University School of Medicine, Department of Radiology, Tokyo (Japan)

    2009-02-15

    Microcirculatory failure after reperfusion is clinically indicated to cause reperfusion injury whereas excessive intracellular calcium ion overload is experimentally proved as a key mechanism of reperfusion injury. We hypothesized that technetium-99m ({sup 99m}Tc) pyrophosphate (Tc-PYP) uptake in injured but viable infarct-related myocardium with preserved myocardial perfusion after reperfusion estimated by thallium-201 ({sup 201}Tl) uptake would be associated with final functional recovery. Dual-isotope Tc-PYP/{sup 201}Tl single-photon emission computed tomography (SPECT) was performed 2 days after successful reperfusion therapy in patients with first acute myocardial infarction, and 50 patients (63 {+-} 13 years old, female 22%) with preserved {sup 201}Tl uptakes of {>=}50% in reperfused myocardium was followed for 1 month. Tc-PYP uptake was assessed as the heart-to-sternum (H/S) ratio. Two-dimensional echocardiography was also performed 2 days and 1 month after reperfusion to evaluate functional recovery. High Tc-PYP uptake, defined as the H/S ratio {>=}0.81, was predictive of chronic phase no functional recovery (73.7% in 14 of 19 patients with high uptake vs 16.1% in five of 31 patients without those, p < 0.0001). After adjustment for potential confounding variables, including electrocardiographic persistent ST segment elevation at 1 h after reperfusion, high Tc-PYP uptake remained independently predictive of no functional recovery with odds ratio of 8.7 (95% confidential interval = 2 to 38.7; p = 0.005). High Tc-PYP uptake in reperfused but viable infarct-related myocardium was a powerful predictor of no functional recovery, which may reflect excessive intracellular calcium ion overload caused by reperfusion injury. Tc-PYP/{sup 201}Tl dual-isotope SPECT imaging can provide prognostic information after reperfusion. (orig.)

  12. Comparative studies on right ventricular pressure and volume overloading by thallium-201 myocardial scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Owada, K.; Tsukahara, Y.; Kijima, M.; Miyazaki, Y.; Ono, K. (Fukushima Medical Coll. (Japan))

    1982-03-01

    Thallium-201 myocardial scintigraphy was performed in 44 patients with various heart diseases including mitral stenosis, atrial septal defect, primary pulmonary hypertension, and left atrial myxoma. The morphological findings of right ventricular (RV) free wall on the scintigram and RV/IVS (interventricular septum) uptake ratio of the images obtained from the left anterior oblique projection were studied in the patients with RV pressure or volume overloading.

  13. Dipyridamole-thallium-201 tomography documenting improved myocardial perfusion with therapy in Kawasaki disease

    Energy Technology Data Exchange (ETDEWEB)

    Nienaber, C.A.; Spielmann, R.P.; Hausdorf, G.

    1988-12-01

    Thallium-201 tomographic perfusion studies after pharmacologic vasodilation were performed in seven children (aged 2 years 8 months to 8 years 7 months), 3 to 20 months after the acute stage of the disease. In all patients coronary aneurysms were seen on cross-sectional echocardiograms. The scintigrams of six children showed no significant regional reduction of myocardial thallium-201 uptake. These children had remained asymptomatic in the follow-up period after the acute inflammatory stage of Kawasaki disease. Persistent and transient thallium defects were present in one child with acute posterolateral myocardial infarction; obstruction of two coronary vessels supplying the defect zones was confirmed by contrast angiography. After 8 months of treatment a follow-up nuclear scan showed marked reduction in the size of the defect and almost complete abolishment of the ischemic reaction. Thus tomographic thallium-201 perfusion scintigraphy in conjunction with vasodilation stress is useful to assess myocardial perfusion in children with Kawasaki disease and demonstrates marked improvement in regional perfusion after adequate medical therapy.

  14. Detection of human collateral circulation by vasodilation-thallium-201 tomography

    Energy Technology Data Exchange (ETDEWEB)

    Nienaber, C.A.; Salge, D.; Spielmann, R.P.; Montz, R.; Bleifeld, W. (University Hospital Eppendorf, Hamburg (Germany, F.R.))

    1990-04-15

    Coronary arteriolar vasodilation may provoke redistribution of flow to collateral-dependent jeopardized myocardium. To assess the physiologic significance of collaterals, 80 consecutive post-infarction patients (age 58 +/- 8 years) underwent vasodilation-redistribution thallium-201 tomographic imaging after administration of 0.56 mg of intravenous dipyridamole/kg body weight. Circumferential profile analysis of thallium-201 uptake and redistribution in representative left ventricular tomograms provided quantitative assessment of transient and fixed defects and separation between periinfarctional and distant inducible hypoperfusion. Tomographic perfusion data were correlated to wall motion and collateral circulation between distinct anatomic perfusion territories. Patients were grouped according to presence (59%) or absence (41%) of angiographically visible collateral channels to jeopardized myocardium. In the presence of collaterals, distant reversible defects were larger than in absence of collaterals (p less than 0.05); the extent of combined periinfarctional and distant redistribution was also larger in collateralized patients (p less than 0.025), whereas the size of the persistent perfusion defect was similar in both groups. By prospective analysis the tomographic perfusion pattern of combined periinfarctional and distant redistribution revealed a sensitivity of 85% and a specificity of 78% for the detection of significant collateral circulation in this group of patients. Thus, using the exhausted flow reserve as a diagnostic tool, vasodilation-thallium-201 tomography has the potential to identify and quantitate collateralized myocardium in post-infarction patients and may guide diagnostic and therapeutic decision-making.

  15. Dilatation of the left ventricular cavity on dipyridamole thallium-201 imaging: A new marker of triple-vessel disease

    Energy Technology Data Exchange (ETDEWEB)

    Takeishi, Y.; Tono-oka, I.; Ikeda, K.; Komatani, A.; Tsuiki, K.; Yasui, S. (Yamagata Univ. School of Medicine (Japan))

    1991-02-01

    To investigate the significance and mechanism of dilatation of the left ventricular cavity on dipyridamole thallium-201 imaging, we performed both dipyridamole thallium-201 imaging and dipyridamole radionuclide angiography on 83 patients with known angiograms. The dipyridamole/delayed ratio of the left ventricular dimension from the thallium-201 image was defined as the left ventricular dilatation ratio (LVDR). An LVDR greater than the mean + two standard deviations in patients without coronary artery disease was defined as abnormal. Twenty-two of 83 patients showed an abnormal LVDR, and 18 of the 22 patients (82%) had triple-vessel disease. By defect and washout analysis, the sensitivity and specificity for correctly identifying the patients as having triple-vessel disease was 72% and 76%, respectively, whereas LVDR had a sensitivity of 72% and a specificity of 93%. When LVDR was used in combination with the defect and washout criteria, sensitivity increased to 84% without a loss of specificity. In those 22 patients with abnormal LVDRs, end-diastolic volume measured by radionuclide angiography did not change after dipyridamole infusion. Dilatation of the left ventricular cavity on dipyridamole thallium-201 imaging reflected relative subendocardial hypoperfusion induced by dipyridamole rather than actual chamber enlargement. The LVDR was moderately sensitive and highly specific for triple-vessel disease and provided complementary information to dipyridamole thallium-201 imaging.

  16. Area at risk can be assessed by iodine-123-meta-iodobenzylguanidine single-photon emission computed tomography after myocardial infarction: a prospective study.

    Science.gov (United States)

    Hedon, Christophe; Huet, Fabien; Ben Bouallegue, Fayçal; Vernhet, Hélène; Macia, Jean-Christophe; Cung, Thien-Tri; Leclercq, Florence; Cade, Stéphane; Cransac, Frédéric; Lattuca, Benoit; Vandenberghe, D'Arcy; Bourdon, Aurélie; Benkiran, Meriem; Vauchot, Fabien; Gervasoni, Richard; D'estanque, Emmanuel; Mariano-Goulart, Denis; Roubille, François

    2018-02-01

    Myocardial salvage is an important surrogate endpoint to estimate the impact of treatments in patients with ST-segment elevation myocardial infarction (STEMI). The aim of this study was to evaluate the correlation between cardiac sympathetic denervation area assessed by single-photon emission computed tomography (SPECT) using iodine-123-meta-iodobenzylguanidine (I-MIBG) and myocardial area at risk (AAR) assessed by cardiac magnetic resonance (CMR) (gold standard). A total of 35 postprimary reperfusion STEMI patients were enrolled prospectively to undergo SPECT using I-MIBG (evaluates cardiac sympathetic denervation) and thallium-201 (evaluates myocardial necrosis), and to undergo CMR imaging using T2-weighted spin-echo turbo inversion recovery for AAR and postgadolinium T1-weighted phase sensitive inversion recovery for scar assessment. I-MIBG imaging showed a wider denervated area (51.1±16.0% of left ventricular area) in comparison with the necrosis area on thallium-201 imaging (16.1±14.4% of left ventricular area, Parea (P=0.23) and was adequately correlated (R=0.56, P=0.0002). Myocardial salvage evaluated by SPECT imaging (mismatch denervated but viable myocardium) was significantly higher than by CMR (P=0.02). In patients with STEMI, I-MIBG SPECT, assessing cardiac sympathetic denervation may precisely evaluate the AAR, providing an alternative to CMR for AAR assessment.

  17. Evaluation of myocardial abnormalities in collagen diseases by thallium-201 myocardial scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Yamano, Shigeru; Kagoshima, Tadashi; Sugihara, Kiyotaka (Nara Medical Univ., Kashihara (Japan)) (and others)

    1993-12-01

    This study was performed to evaluate myocardial abnormalities in patients with collagen diseases by exercise and rest thallium-201 myocardial scintigrams. A total of 65 patients without ischemic ECG changes, consisting of 18 with systemic lupus erythematosus (SLE), 18 with polymyositis (PM), 8 with progressive systemic sclerosis (PSS), and 21 with Sjoegren's syndrome (SjS), was enrolled in this study. Reversible exercise-induced defects scintigraphically suggesting myocardial ischemia were noted in 8 cases of SLE, 4 cases of PM, 4 cases of PSS, and 3 cases of SjS. Nineteen patients had exercise-induced defects and underwent cardiac catheterization, 8 of whom had normal coronary angiograms. Fixed hypoperfusion areas were observed in one case of SLE, 6 cases of PM and 3 cases of SjS. Rest thallium-201 myocardial scintigram disclosed hypoperfusion areas which were not induced by exercise in 2 cases of SLE, 3 cases of PM, one case of PSS and 5 cases of SjS. Echocardiogram showed no significant differences in ejection fraction and % fractional shortening between the disease groups and healthy control group. These findings suggest that patients with collagen diseases have abnormalities of coronary circulation at the level of the intramural vasculature before cardiac function impairment, myocardial fibrosis and functional abnormalities at the cell membrane. (author).

  18. Qualitative evaluation of coronary flow during anesthetic induction using thallium-201 perfusion scans

    Energy Technology Data Exchange (ETDEWEB)

    Kleinman, B.; Henkin, R.E.; Glisson, S.N.; el-Etr, A.A.; Bakhos, M.; Sullivan, H.J.; Montoya, A.; Pifarre, R.

    1986-02-01

    Qualitative distribution of coronary flow using thallium-201 perfusion scans immediately postintubation was studied in 22 patients scheduled for elective coronary artery bypass surgery. Ten patients received a thiopental (4 mg/kg) and halothane induction. Twelve patients received a fentanyl (100 micrograms/kg) induction. Baseline thallium-201 perfusion scans were performed 24 h prior to surgery. These scans were compared with the scans performed postintubation. A thallium-positive scan was accepted as evidence of relative hypoperfusion. Baseline hemodynamic and ECG data were obtained prior to induction of anesthesia. These data were compared with the data obtained postintubation. Ten patients developed postintubation thallium-perfusion scan defects (thallium-positive scan), even though there was no statistical difference between their baseline hemodynamics and hemodynamics at the time of intubation. There was no difference in the incidence of thallium-positive scans between those patients anesthetized by fentanyl and those patients anesthetized with thiopental-halothane. The authors conclude that relative hypoperfusion, and possibly ischemia, occurred in 45% of patients studied, despite stable hemodynamics, and that the incidence of these events was the same with two different anesthetic techniques.

  19. Effects of adenosine and a selective A2A adenosine receptor agonist on hemodynamic and thallium-201 and technetium-99m-sestaMIBI biodistribution and kinetics.

    Science.gov (United States)

    Mekkaoui, Choukri; Jadbabaie, Farid; Dione, Donald P; Meoli, David F; Purushothaman, Kailasnath; Belardinelli, Luiz; Sinusas, Albert J

    2009-10-01

    The purpose of this study was to compare a selective A(2A) adenosine receptor agonist (regadenoson) with adenosine in clinically relevant canine models with regard to effects on hemodynamics and thallium-201 ((201)Tl) and technetium-99m ((99m)Tc)-sestaMIBI biodistribution and kinetics. The clinical application of vasodilator stress for perfusion imaging requires consideration of the effects of these vasodilating agents on systemic hemodynamics, coronary flow, and radiotracer uptake and clearance kinetics. Sequential imaging and arterial blood sampling was performed on control, anesthetized closed-chest canines (n = 7) to evaluate radiotracer biodistribution and kinetics after either a bolus administration of regadenoson (2.5 microg/kg) or 4.5-min infusion of adenosine (280 microg/kg). The effects of regadenoson on coronary flow and myocardial radiotracer uptake were then evaluated in an open-chest canine model of a critical stenosis (n = 7). Results from ex vivo single-photon emission computed tomography were compared with tissue well-counting. The use of regadenoson compared favorably with adenosine in regard to the duration and magnitude of the hemodynamic effects and the effect on (201)Tl and (99m)Tc-sestaMIBI biodistribution and kinetics. The arterial blood clearance half-time was significantly faster for (99m)Tc-sestaMIBI (regadenoson: 1.4 +/- 0.03 min; adenosine: 1.5 +/- 0.08 min) than for (201)Tl (regadenoson: 2.5 +/- 0.16 min, p adenosine: 2.7 +/- 0.04 min, p regadenoson stress was significantly greater than the relative perfusion defect with (99m)Tc-sestaMIBI (0.69 +/- 0.03%, p regadenoson produced a hyperemic response comparable to a standard infusion of adenosine. The biodistribution and clearance of both (201)Tl and (99m)Tc-sestaMIBI during regadenoson were similar to adenosine vasodilation. Ex vivo perfusion images under the most ideal conditions permitted detection of a critical stenosis, although (201)Tl offered significant advantages over (99m

  20. Comparison of 8-frame and 16-frame thallium-201 gated myocardial perfusion SPECT for determining left ventricular systolic and diastolic parameters.

    Science.gov (United States)

    Kurisu, Satoshi; Sumimoto, Yoji; Ikenaga, Hiroki; Watanabe, Noriaki; Ishibashi, Ken; Dohi, Yoshihiro; Fukuda, Yukihiro; Kihara, Yasuki

    2017-07-01

    The myocardial perfusion single photon emission computed tomography synchronized with the electrocardiogram (gated SPECT) has been widely used for the assessment of left ventricular (LV) systolic and diastolic functions using Quantitative gated SPECT. The aim of this study was to compare the effects of 8-frame and 16-frame thallium-201 (Tl-201) gated SPECT for determining LV systolic and diastolic parameters. The study population included 42 patients with suspected coronary artery disease who underwent gated SPECT by clinical indication. LV systolic and diastolic parameters were assessed on 8-frame and 16-frame gated SPECT. There were good correlations in end-diastolic volume (r = 0.99, p < 0.001), end-systolic volume (ESV) (r = 0.97, p < 0.001) and ejection fraction (EF) (r = 0.95, p < 0.001) between 8-frame and 16-frame gated SPECT. Bland-Altman plot showed a significant negative slope of -0.08 in EDV indicating a larger difference for larger EDV. Eight-frame gated SPECT overestimated ESV by 2.3 ml, and underestimated EF by -4.2% than 16-frame gated SPECT. There were good correlations in peak filling rate (PFR) (r = 0.87, p < 0.001), one third mean filling rate (r = 0.87, p < 0.001) and time to PFR (r = 0.61, p < 0.001) between 8-frame and 16-frame gated SPECT. Eight-frame gated SPECT underestimated PFR by -0.22 than 16-frame gated SPECT. Eight-frame gated SPECT estimated as much MFR/3 and TPFR as 16-frame gated SPECT. According to the data, the study suggested that 8-frame Tl-201 gated SPECT could underestimate systolic and/or diastolic parameter when compared with 16-frame gated SPECT.

  1. Evaluation of myocardial abnormalities in patients with collagen diseases by thallium-201 myocardial scintigram

    Energy Technology Data Exchange (ETDEWEB)

    Yamano, Shigeru (Nara Medical Univ., Kashihara (Japan))

    1992-08-01

    This study was performed to evaluate myocardial lesions in patients with collagen diseases by rest and exercise thallium-201 myocardial scintigraphies. A total of 76 patients without ischemic ECG changes, consisting of 27 cases of systemic lupus erythematosus (SLE), 17 cases of polymyositis or dermatomyositis (PM[center dot]DM), 11 cases of progressive systemic sclerosis (PSS), and 21 cases of Sjoegren's syndrome (SjS), were enrolled in this study. Reversible exercise-induced defects suggesting myocardial ischemia were noted in 12 cases of SLE, 5 cases of PM[center dot]DM, 3 cases of PSS, and 3 cases of SjS. Of the 23 patients who had exercise-induced defects, 9 patients showed normal coronary angiograms by cardiac catheterization. Fixed hypoperfusion areas were observed in 5 cases of SLE, 6 cases of PM[center dot]DM, 4 cases of PSS and 3 cases of SjS. Rest thallium-201 myocardial scintigraphy disclosed hypoperfusion areas, which were not induced by exercise, in 1 case of SLE, 4 cases of PM[center dot]DM, 1 case of PSS and 5 cases of SjS. Endomyocardial biopsy was performed on 20 patients. Myocardial lesions in PM[center dot]DM and PSS were more severe and wide spread than in SLE. Ejection fraction and fractional shortening evaluated by echocardiography had no significant differences between each disease group and the healthy control group. These findings suggest that patients with collagen diseases show the presence of abnormalities of coronary circulation at the level of the intramyocardial vasculature in the stage before impairment of cardiac function, myocardial fibrosis and functional abnormalities of the cell membrane level that were not dependent on myocardial ischemia. (author).

  2. Septal myocardial perfusion imaging with thallium-201 in the diagnosis of proximal left anterior descending coronary artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Pichard, A.D.; Wiener, I.; Martinez, E.; Horowitz, S.; Patterson, R.; Meller, J.; Goldsmith, S.J.; Gorlin, R.; Herman, M.V.

    1981-07-01

    The use of myocardial perfusion imaging (MPI) to identify obstructive coronary disease of the left anterior descending coronary artery proximal to the first septal perforator (prox LAD) was studied in 60 patients. Perfusion of the septum and anteroapical areas with thallium-201 injected during exercise was compared to results of coronary arteriography. Septal MPI defect was found in 92.3% of patients with obstruction of the proximal LAD, 27.7% of patients with obstruction of LAD distal to first septal perforator, 0% in patients with obstructions involving right or circumflex arteries, and in 10.5% of patients without coronary disease. Anteroapical MPI defects were found with similar frequency in the three groups with obstructive coronary disease. Septal MPI defect had a sensitivity of 92.3% and specificity of 85.4% in the diagnosis of proximal LAD disease. Normal septal perfusion with thallium-201 virtually excluded proximal LAD disease.

  3. Thallium-201 SPECT in the diagnosis of head and neck cancer.

    Science.gov (United States)

    Valdés Olmos, R A; Balm, A J; Hilgers, F J; Koops, W; Loftus, B M; Tan, I B; Muller, S H; Hoefnagel, C A; Gregor, R T

    1997-06-01

    The accuracy of SPECT with 201Tl-chloride for the diagnosis of primary tumors, lymph node metastases and recurrences in head and neck cancer was evaluated for clinical applicability. SPECT images, obtained 60 min after administration of 150 MBq 201Tl-chloride, were compared with clinical, CT and/or MRI and histology results. In addition, whole-body images were obtained to detect distant metastases. In 79 patients studied for primary tumors (principally larynix, hypopharynx, oropharynx, nasopharynx and oral cavity), 201Tl SPECT correctly identified 69 of 73 (95% versus 88% for CT/MRI) histologically confirmed malignancies including 63 squamous-cell carcinomas. The method localized four occult naso- and oropharynx carcinomas not seen on CT/MRI and was correctly negative in two patients without tumor and in three of four patients with no confirmed primary tumor in the head and neck. With respect to regional spread, only patients who had cervical lymph node dissection were evaluated, and the findings were recorded per side of the neck. Thallium-201 SPECT correctly identified metastases in 31 of 36 neck dissections with proven lymph node involvement (86%), was correctly negative in nine and false-positive in one. Although the sensitivity of CT/MRI was clearly higher (97%), considerably more false-positive cases affected its accuracy (81% versus 87% for SPECT). In 30 patients investigated for recurrences, 201Tl SPECT correctly identified 27 of 29 microscopically confirmed tumor sites (93%) and was correctly negative in seven. Sensitivity of CT/MRI was lower (76%), and a greater number of false-positives (seven versus three for SPECT) further decreased its accuracy (64% versus 87% for SPECT). Distant metastases were detected in five patients. Thallium-201 SPECT appears to be an accurate method for the diagnosis of head and neck cancer. The method is particularly useful for detection of occult head and neck tumors and for assessing recurrences. It also may be of

  4. Follow-up Thallium-201 scintigraphy after mantle field radiotherapy for Hodgkin's disease

    Energy Technology Data Exchange (ETDEWEB)

    Pierga, J.Y.; Girinski, T.; Henry-Amar, M. (Institut Gustave Roussy, Villejuif (France)); Maunoury, C.; Valette, H.; Tchernia, G.; Desgrez, A. (Centre Hospitalier de Bicetre, Le Kremlin-Bicetre (France)); Socie, G. (Institut Gustave Roussy, Villejuif (France) Hopital St Louis, Paris (France)); Cosset, J.M. (Institut Gustave Roussy, Villejuif (France) Institut Curie, Paris (France))

    1993-04-02

    Assessment of the long-term cardiac effects of mediastinal radiotherapy for Hodgkin's disease, by Thallium scintigraphy. 32 patients (14 males and 18 females) who underwent mantle field radiotherapy for Hodgkin's disease were included in this study. Twenty patients received 4 fractions of 2.5 Gy per week and 12, five fraction of 2 Gy per week, delivered on alternate days. All the patients, except three, performed exercise testing electrocardiogram and Thallium-201 tomoscintigraphy. The average time interval from completion of treatment to the study was 7 years (range 3--13 years). No patients had clinical symptoms of cardiac disease. Mean age at the time of the study was 35 years (range 23--48 years). Two electrocardiograms revealed left bundle branch block and the patients were excluded from the study. Only one out of 27 exercise electrocardiograms was abnormal in a patient with mitral valve prolapse, who was also excluded from the study. Twenty-six scintigraphies were evaluable. Twenty-two (85%) were clearly abnormal with partial or complete redistribution on delayed images. The anterior region was affected in 19 of these cases (86%). Four explorations were undoubtedly normal. Coronary angiography was not performed for ethical reasons in these asymptomatic patients. Despite possible false positive tests, the high rate of abnormality (85%) in this small series is striking. These preliminary data justify larger studies and a close long-term follow-up of these patients. 24 refs., 1 fig., 2 tabs.

  5. Clinicopathologic correlation study of thallium-201 myocardial scintigraphy in diagnosis of myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Chida, Kouji; Sugiura, Masaya; Ohkawa, Shin-ichiro

    1987-05-01

    In a series of 1,000 consecutive autopsy cases, we evaluated the clinical utility of thallium-201 (Tl-201) myocardial scintigraphy and electrocardiography (ECG) in 101 patients who had been studied while alive. Fifty-five cases had myocardial infarctions (MI) at autopsy. The Tl-201 scintigram and ECG in diagnosis of MI showed sensitivities of 68 % and 60 %, specificities of 87 % and 83 %, and diagnostic accuracies of 76 % and 70 %, respectively. The sensitivity of the Tl-201 scintigram was 70 % in anterior MI, 80 % in postero-inferior MI, 25 % in lateral and subendocardial infarction. The sensitivity was 88 % for large massive MI, but was low in scattered (50 %) or middle-sized MI (17 %). The diagnostic limit of the resolution of Tl-201 scintigrams was 4.5 cm in long diameter. All 8 cases with MI of less than 4 cm could not be diagnosed with the technique. There were 48 cases of large MI (more than 5 cm), but 8 cases could not be diagnosed by scintigraphy because of non-transmural or scattered MI. A comparison of the Tl-201 scintigram and ECG showed that 27 cases out of 60 cases were diagnosed by both methods, 14 only by the Tl-201 scintigram, 9 only by ECG and 10 by neither method.

  6. Thallium-201 for cardiac stress tests: residual radioactivity worries patients and security.

    Science.gov (United States)

    Geraci, Matthew J; Brown, Norman; Murray, David

    2012-12-01

    A 47-year-old man presented to the Emergency Department (ED) in duress and stated he was "highly radioactive." There were no reports of nuclear disasters, spills, or mishaps in the local area. This report discusses the potential for thallium-201 (Tl-201) patients to activate passive radiation alarms days to weeks after nuclear stress tests, even while shielded inside industrial vehicles away from sensors. Characteristics of Tl-201, as used for medical imaging, are described. This patient was twice detained by Homeland Security Agents and searched after he activated radiation detectors at a seaport security checkpoint. Security agents deemed him not to be a threat, but they expressed concern regarding his health and level of personal radioactivity. The patient was subsequently barred from his job and sent to the hospital. Tl-201 is a widely used radioisotope for medical imaging. The radioactive half-life of Tl-201 is 73.1h, however, reported periods of extended personal radiation have been seen as far out as 61 days post-administration. This case describes an anxious, but otherwise asymptomatic patient presenting to the ED with detection of low-level personal radiation. Documentation should be provided to and carried by individuals receiving radionuclides for a minimum of five to six half-lives of the longest-lasting isotope provided. Patients receiving Tl-201 should understand the potential for security issues; reducing probable tense moments, confusion, and anxiety to themselves, their employers, security officials, and ED staff. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Superconducting Single Photon Detectors

    NARCIS (Netherlands)

    Dorenbos, S.N.

    2011-01-01

    This thesis is about the development of a detector for single photons, particles of light. New techniques are being developed that require high performance single photon detection, such as quantum cryptography, single molecule detection, optical radar, ballistic imaging, circuit testing and

  8. Biphasic thallium 201 SPECT-imaging for the noninvasive diagnosis of myocardial perfusion abnormalities in a child with Kawasaki disease--a case report

    Energy Technology Data Exchange (ETDEWEB)

    Hausdorf, G.; Nienaber, C.A.; Spielman, R.P.

    1988-02-01

    The mucocutaneous lymph node syndrome (Kawasaki disease) is of increasing importance for the pediatric cardiologist, for coronary aneurysms with the potential of thrombosis and subsequent stenosis can develop in the course of the disease. The authors report a 2 1/2-year-old female child in whom, fourteen months after the acute phase of Kawasaki disease, myocardial infarction occurred. Biphasic thallium 201 SPECT-imaging using dipyridamole depicted anterior wall ischemia and inferolateral infarction. This case demonstrates that noninvasive vasodilation-redistribution thallium 201 SPECT-imaging has the potential to predict reversible myocardial perfusion defects and myocardial necrosis, even in small infants with Kawasaki disease.

  9. Single-photon imaging

    CERN Document Server

    Seitz, Peter

    2011-01-01

    The acquisition and interpretation of images is a central capability in almost all scientific and technological domains. In particular, the acquisition of electromagnetic radiation, in the form of visible light, UV, infrared, X-ray, etc. is of enormous practical importance. The ultimate sensitivity in electronic imaging is the detection of individual photons. With this book, the first comprehensive review of all aspects of single-photon electronic imaging has been created. Topics include theoretical basics, semiconductor fabrication, single-photon detection principles, imager design and applications of different spectral domains. Today, the solid-state fabrication capabilities for several types of image sensors has advanced to a point, where uncoooled single-photon electronic imaging will soon become a consumer product. This book is giving a specialist´s view from different domains to the forthcoming “single-photon imaging” revolution. The various aspects of single-photon imaging are treated by internati...

  10. Pentoxifylline (Trental) does not inhibit dipyridamole-induced coronary hyperemia: Implications for dipyridamole-thallium-201 myocardial imaging

    Energy Technology Data Exchange (ETDEWEB)

    Brown, K.A.; Slinker, B.K. (Univ. of Vermont College of Medicine, Burlington (USA))

    1990-06-01

    Dipyridamole-thallium-201 imaging is often performed in patients unable to exercise because of peripheral vascular disease. Many of these patients are taking pentoxifylline (Trental), a methylxanthine derivative which may improve intermittent claudication. Whether pentoxifylline inhibits dipyridamole-induced coronary hyperemia like other methylxanthines such as theophylline and should be stopped prior to dipyridamole-thallium-201 imaging is unknown. Therefore, we studied the hyperemic response to dipyridamole in seven open-chest anesthetized dogs after pretreatment with either pentoxifylline (0, 7.5, or 15 mg/kg i.v.) or theophylline (3 mg/kg i.v.). Baseline circumflex coronary blood flows did not differ significantly among treatment groups. Dipyridamole significantly increased coronary blood flow before and after 7.5 or 15 mm/kg i.v. pentoxifylline (p less than 0.002). Neither dose of pentoxifylline significantly decreased the dipyridamole-induced hyperemia, while peak coronary blood flow was significantly lower after theophylline (p less than 0.01). We conclude that pentoxyifylline does not inhibit dipyridamole-induced coronary hyperemia even at high doses.

  11. Comparison of arbutamine stress and treadmill exercise thallium-201 SPECT: Hemodynamics, safety profile and diagnostic accuracy

    Energy Technology Data Exchange (ETDEWEB)

    Kiat, H.; Berman, D.S. [Cedars-Sinai Medical Centre, Los Angeles, California, LA (United States)

    1998-02-01

    Full text: Arbutamine (ARB), a new pharmacologic stress agent with enhanced chronotropic property compared to dobutamine, was compared with treadmill (TM) exercise testing (Ex) in a multicenter study using thallium-201 (Tl) SPECT. Of the total of 184 patients who underwent ARB, 69 also had TM stress and quantitative coronary angiography. Fifty-eight patients with a low pretest likelihood of CAD also underwent ARB study for evaluation of test specificity (normalcy rate). Tl scans were scored by a central laboratory using a 20 segment (seg)/scan visual analysis (5 point system: 0=normal, 4-absent uptake). Maximum heart rate (HR) by ARB and Ex was 122 vs 141 bpm (p<0.05). Mean %HR change from baseline was similar (79% vs 82%, respectively, p=ns). Maximum systolic BP for ARB and Ex was 173 vs 175 mmHg, and mean % change from baseline was 24% vs 28% (p=ns). Sensitivity for detecting CAD (270% stenosis) by ARB Tl was 94% and 97% by Ex Tl (p=ns). Stress Tl SPECT segmental agreement for presence of defect between ARB and Ex was 92% (kappa=0.8, p<0.001). Exact segmental stress Tl score (0-4 grading) agreement was 83 % (kappa=0.7, p<0.001). Among 346 segs with stress defects by both ARB and Ex defect reversibility agreement was 86% (kappa=0.7, p<0.001). The normalcy rate for ARB TI-SPECT among patients with a low likelihood of CAD was 90%. Adverse events were mostly mild (tremor: 23%, flushing: 10%, headache: 10%, paraesthesia: 8%, dizziness: 8%, hot flushes: 4%). Arrhythimia of clinical concern occurred in 8% (10/122) of ARB patients who had cardiac catheterisation and in 1.4% (1/69) of patients who had stress Tl. Of all 184 patients with ARB stress, ARB was discontinued due to arrhythmia in 7(5%) and 1 patient had IV Metoprolol for frequent ventricular couplets. Sustained arrhythmias were not observed

  12. Single photon quantum cryptography.

    Science.gov (United States)

    Beveratos, Alexios; Brouri, Rosa; Gacoin, Thierry; Villing, André; Poizat, Jean-Philippe; Grangier, Philippe

    2002-10-28

    We report the full implementation of a quantum cryptography protocol using a stream of single photon pulses generated by a stable and efficient source operating at room temperature. The single photon pulses are emitted on demand by a single nitrogen-vacancy color center in a diamond nanocrystal. The quantum bit error rate is less that 4.6% and the secure bit rate is 7700 bits/s. The overall performances of our system reaches a domain where single photons have a measurable advantage over an equivalent system based on attenuated light pulses.

  13. QUANTUM CRYPTOGRAPHY: Single Photons.

    Science.gov (United States)

    Benjamin, S

    2000-12-22

    Quantum cryptography offers the potential of totally secure transfer of information, but as Benjamin discusses in this Perspective, its practical implementation hinges on being able to generate single photons (rather than two or more) at a time. Michler et al. show how this condition can be met in a quantum dot microdisk structure. Single molecules were also recently shown to allow controlled single-photon emission.

  14. Thallium-201 myocardial scintigraphy in patients with normal coronary arteries and normal left ventriculogram. Comparison with hemodynamic, metabolic and morphologic findings

    Energy Technology Data Exchange (ETDEWEB)

    Loesse, B.; Kuhn, H.; Rafflenbeul, D.; Kroenert, H.; Hort, W.; Feinendegen, L.E.; Loogen, F.

    1980-01-01

    36 consecutive patients with chest pain and/or severe ventricular dysrhythmias, but normal coronary arteries and normal left ventriculogram, underwent thallium-201 myocardial imaging at rest and during exercise. The myocardial scintigram was abnormal in 27 patients (group A) and normal in only 9 patients (group B).

  15. Dipyridamole-loading scintigraphy in patients with subendocardial infarction using single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Mori, Kiyoo; Masuda, Masanosuke (Hoju Memorial Hospital, Tatsunokuchi, Ishikawa (Japan)); Bunkou, Hisashi

    1988-12-01

    To detect myocardial lesions in patients with subendocardial (nontransmural) infarction, myocardial perfusion images of thallium-201 (Tl-201), using single photon emission computed tomography, were obtained in 17 patients during and three hours after coronary vasodilatation induced by the administration of dipyridamole. Controls consisted of 28 patients with transmural infarction and 11 with angina pectoris. Dipyridamole was infused intravenously at a rate of 0.142 mg/kg per min for four min, and the washout rate of Tl-201 was calculated by the segmental ROI method. Many patients with nontransmural infarction exhibited various Tl-201 myocardial perfusion images. The prevalence of redistribution among patients with nontransmural infarction was 88.2% (15 of 17), and its reverse redistribution was 64.7% (11 of 17). Every subject exhibited a number of abnormal Tl-201 myocardial perfusion images. In patients with nontransmural infarction the occurence of reverse redistribution images was significantly higher (64.7%) compared to those with transmural infarction (10.7%), and the occurrence of redistribution images was significantly higher (88.2%) compared to those with angina pectoris (45.5%). The abnormal perfusion images most frequently present in the areas corresponding to the sites of ST-T changes on ECG were reverse redistribution (26.7%), redistribution (17.3%), and fixed defect (6.7%) in order. The phenomenon of reverse redistribution images was found irrespective of stenotic coronary artery lesions on selective coronary angiography. Most areas corresponding to the sites of reverse redistribution showed ST-T changes on ECG and high washout rates of Tl-201. (J.P.N.).

  16. Detection and dosimetry of gamma ray emitted from thallium-201 and technetium-99m based on chemiluminescence technique

    Energy Technology Data Exchange (ETDEWEB)

    Shourian, Mostafa [Laboratory of Microanalysis, Institute of Biochemistry and Biophysics, University of Tehran, P.O. Box 13145-1384, Tehran (Iran, Islamic Republic of); Tavakoli, Hassan, E-mail: tavakoli@ibb.ut.ac.i [Faculty of Medicine, Department of Physiology and Biophysics, Faculty of Medicine, Baqiyatollah University of Medical Sciences, P.O. Box 19395-6558, Tehran (Iran, Islamic Republic of); Ghourchian, Hedayatollah, E-mail: hadi@ibb.ut.ac.i [Laboratory of Microanalysis, Institute of Biochemistry and Biophysics, University of Tehran, P.O. Box 13145-1384, Tehran (Iran, Islamic Republic of); Rafiee-Pour, Hossain-Ali [Laboratory of Microanalysis, Institute of Biochemistry and Biophysics, University of Tehran, P.O. Box 13145-1384, Tehran (Iran, Islamic Republic of)

    2010-09-15

    This report describes the detection and dosimetry of gamma ray emitted from Thallium-201 ({sup 201}Tl) and Technetium-99m ({sup 99m}Tc) based on chemiluminescence technique. H{sub 2}O{sub 2} produced by two gamma emitter radioisotopes of {sup 201}Tl and {sup 99m}Tc were quantitatively measured by chemiluminescence method. Upon producing H{sub 2}O{sub 2} in a luminol alkaline solution, in the presence of diperiodatocuprate, as catalyst a chemical reaction was accrued and consequently the emitted light was measured. The determined H{sub 2}O{sub 2} concentration was correlated with the gamma ray detection and dosimetry. The sensitivity of chemiluminescence technique for {sup 201}Tl and {sup 99m}Tc dosimetry was determined to be 0.20 and 0.08 MBq/l (Mega Becquerel per liter) respectively (R.S.D. = %5, N = 3). The plotted calibration curves showed detection limits of 3.24 and 1.76 MBq/l for {sup 201}Tl and {sup 99m}Tc, respectively.

  17. Myocardial infarction diagnosis with body surface potential mapping, electrocardiography, vectorcardiography and thallium-201 scintigraphy: a correlative study with left ventriculography.

    Science.gov (United States)

    Ackaoui, A; Nadeau, R; Sestier, F; Savard, P; Primeau, R; Lemieux, R; Descary, M C

    1985-01-01

    In 35 subjects with typical or atypical angina and/or documented myocardial infarction (MI), body surface potential maps (BSPMs), ECG, VCG and rest Thallium-201 (T1-201) have been compared to left ventriculography (LVG). BSPMs were recorded with 26 ECGs, and BSPM abnormalities for MI cases were considered to be areas of normally positive potentials that have become negative. Subjects with MI were classified according to the segmental localization and degree of asynergy on LVG. Moderate anterolateral and apical asynergy were found to correlate with BSPM diagnosis of anterolateral MI and ischemia, severe anterolateral and apical asynergy with BSPM diagnosis of anterolateral MI and ischemia, and moderate diaphragmatic and/or posterobasal asynergy with BSPM diagnosis of posterior MI. Simultaneous anterior and posterior asynergy were found for BSPM diagnosis of anterior with posterior MI. Subjects with no LVG asynergy had normal BSPMs. BSPM diagnosis had the highest correlation coefficient with the LVG diagnosis (r = 0.88). ECG and VCG showed similar results with r = 0.65 and 0.71 respectively, while T1-201 had r = 0.55. The examination of our BSPMs, as well as the ECG, VCG and T1-201, did not permit to detect apical damage in presence of anterior MI, and posterobasal damage in the presence of inferoposterior MI. It is concluded that BSPMs are slightly superior to ECG and VCG for diagnosis of MI.

  18. Functional Significance of Angiographic Collaterals in Patients with Totally Occluded Right Coronary Artery: Intracoronary Thallium-201 Scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Do Yun; Lee, Jong Doo; Cho, Seung Yun; Shim, Won Heum; Ha, Jong Won; Kim, Han Soo; Kwon, Hyuk Moon; Jang, Yang Soo; Chung, Nam Sik; Kim, Sung Soon [Yonsei University College of Medicine, Seoul (Korea, Republic of); Park, Chang Yun; Kim, Young Soo [Inje University College of Medicine, Seoul (Korea, Republic of)

    1993-07-15

    To compare the myocardial viability in patients suffering from total occlusion of the right coronary artery (RCA) with the angiographic collaterals, intracoronary injection of Thallium-201 (T1-201) was done to 14 coronary artery disease (CAD) patients (pts) with total occlusion of RCA and into four normal subjects for control. All 14 CAD pts had Grade 2 or 3 collateral circulations. There were 14 male and 4 females, and their ages ranged from 31 to 70 years. In nine pts, T1-201 was injected into left main coronary artery (LCA) (300 approx 350 mu Ci) to evaluate the myocardial viability of RCA territory through collateral circulations. The remaining five pts received T1-201 into RCA (200-250 mu Ci) because two had intraarterial bridging collaterals and three had previous successful PTCA. Planar and SPECT myocardial perfusion images were obtained 30 minutes, and four to five hours after T1-201 reinjection. Intravenous T1-201 reinjection (six pts) or {sup 99m}Tc-MIBI (two pts) were also performed in eight CAD pts. Intracoronary myocardial perfusion images were compared with intravenous T1-201(IV T1-201) images, EGG, and ventriculography. Intracoronary TI-201 images proved to be superior to that of IV T1-201 due to better myocardial to background uptake ratio and more effective in the detection of viable tissue. We also found that perfusion defects were smaller on intracoronary T1-201 images than those on the IV T1-201. All of the 14 CAD pts had either mostly viable myocardium (seven pts) or large area of T1-201 perfusion (seven pts) in RCA territory, however ventriculographic wall motion and ECG did not correlate well with intracoronary myocardial perfusion images. In conclusion, total RCA occlusion patients with well developed collateral circulation had large area of viable myocardial in the corresponding territory.

  19. Disease stage classification in hypertrophic cardiomyopathy by dual analysis of iodine-123-labeled metaiodobenzylguanidine and thallium-201 myocardial scintigraphies

    Energy Technology Data Exchange (ETDEWEB)

    Hiasa, Go [Ehime Univ., Matsuyama (Japan). School of Medicine

    2001-08-01

    Many patients with hypertrophic cardiomyopathy (HCM) gradually changes from typical myocardial hypertrophy to dilated cardiomyopathy-like features. However, it is difficult to estimate the disease stage in HCM. To determine the disease stage, dual analysis of iodine-123-labeled metaiodobenzylguanidine ({sup 123}I-MIBG) and thallium-201 ({sup 201}Tl) myocardial scintigraphies were performed in 108 HCM patients. According to the scintigraphic distribution patterns, patients were divided into three groups. Group A (n=15): normal distributions of both {sup 123}I-MIBG and {sup 201}Tl, group B (n=71): normal {sup 201}Tl and low {sup 123}I-MIBG patterns, group C (n=22): low distributions of both scintigraphies. The decrease in {sup 201}Tl uptake was observed in only group C. Concerning {sup 123}I-MIBG, heart-to-mediastinum ratio (H/M) and washout rate (WOR) had good correlations with left ventricular systolic functions. H/M was decreased and WOR was increased in order of C, B and A groups. Left ventricular diastolic function reflected by isovolumic relaxation time was longer in group B than in group A. Attenuated left ventricular hypertrophy, enlarged left ventricular volumes, impaired left ventricular functions and serious clinical symptoms were observed in only group C. Myocardial sympathetic abnormalities in group B may be mainly due to myocardial hypertrophy, and those in group C may be due to myocardial injury. Dual analysis of {sup 123}I-MIBG and {sup 201}Tl scintigraphies may be useful to classify disease stages of HCM. (author)

  20. Comparative study of body surface isopotential map, left ventriculogram and thallium-201 myocardial scintigram in patients with old lateral myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Naoyuki

    1988-01-01

    In 16 patients with old lateral myocardial infarction, body surface isopotential maps and 12 lead electrocardiograms were compared with left ventriculographic findings. In addition 8 of these subjects were performed thallium-201 myocardial scintigraphy in order to determine the location and extent of myocardial necrosis. Common 12 lead electrocardiographic findings of the subjects were initial Q waves more than 30 msec and inverted T waves in only aVL lead. The patients were classified into 4 groups according to the location and extent of ventricular wall motion abnormalities group I (6 cases) showed hypokinesis in the anterior segment, group II (5 cases): akinesis in the anterior segment and hypokinesis in the seg. 6, group III (4 cases): hypokinesis in the anterior segment and seg. 7, group IV (1 case): hypokinesis in the anterior segment and seg. 4, 7. And each of the 4 groups demonstrated characteristic findings of surface isopotential maps. Group II with coexisting hypokinesis in the seg. 6 showed surface isopotential maps additional pattern of anterior myocardial infarction, and group III with coexisting hypokinesis in the seg. 7 showed additional patterns of posterior myocardial infarction. The classification according to the abnormality of ventricular wall motion was also conformed with the thallium-201 myocardial scintigraphic findings except one case. These results suggest that body surface isopotential map is more useful than the 12 lead electrocardiogram in detecting the location and extent of left ventricular wall motion abnormality in patients with old lateral myocardial infarction. (author) 53 refs.

  1. Single photon source characterization with a superconducting single photon detector.

    Science.gov (United States)

    Hadfield, Robert H; Stevens, Martin J; Gruber, Steven S; Miller, Aaron J; Schwall, Robert E; Mirin, Richard P; Nam, Sae Woo

    2005-12-26

    Superconducting single photon detectors (SSPD) based on nanopatterned niobium nitride wires offer single photon counting at fast rates, low jitter, and low dark counts, from visible wavelengths well into the infrared. We demonstrate the first use of an SSPD, packaged in a commercial cryocooler, for single photon source characterization. The source is an optically pumped, microcavity-coupled InGaAs quantum dot, emitting single photons at 902 nm. The SSPD replaces the second silicon Avalanche Photodiode (APD) in a Hanbury-Brown Twiss interferometer measurement of the source second-order correlation function, g(2)( ?). The detection efficiency of the superconducting detector system is >2 % (coupling losses included). The SSPD system electronics jitter is 170 ps, versus 550 ps for the APD unit, allowing the source spontaneous emission lifetime to be measured with improved resolution.

  2. Syndrome of diminished vasodilator reserve of the coronary microcirculation (microvascular angina or syndrome X): Diagnosis by combined atrial pacing and thallium 201 imaging--a case report

    Energy Technology Data Exchange (ETDEWEB)

    Magarian, G.J.; Palac, R.; Reinhart, S. (Veterans Administration Medical Center, Portland, OR (USA))

    1990-08-01

    Patients with angina-like chest pain without evidence of epicardial coronary artery disease or coronary arterial vasospasm are becoming increasingly recognized. These are often related to noncardiac causes including esophageal, musculoskeletal, and hyperventilatory or panic states. However, recently a subgroup of such patients are being recognized as having true myocardial ischemia and chest pain on the basis of diminished coronary microvascular vasodilatory reserve (microvascular ischemia or Syndrome X). The authors describe such a patient who was found to have replication of anginal pain associated with a reversible ischemic defect on thallium 201 imaging during atrial pacing, suggesting ischemia in this myocardial segment. Resolution of angina and ST segment electrocardiographic changes of ischemia occurred with cessation of pacing. We believe this is the first report of a patient with this form of myocardial ischemia diagnosed by this method and should be considered in patients with anginal chest pain after significant coronary artery disease and coronary vasospasm have been excluded.

  3. Single photon and nonlocality

    Indian Academy of Sciences (India)

    In a paper by Home and Agarwal [1], it is claimed that quantum nonlocality can be revealed in a simple interferometry experiment using only single particles. A critical analysis of the concept of hidden variable used by the authors of [1] shows that the reasoning is not correct.

  4. SINGLE: single photon sensitive cryogenic light detectors

    Science.gov (United States)

    Biassoni, Matteo; SINGLE Collaboration

    2017-09-01

    Thermal detectors operated at few mK as calorimeters are a powerful tool for the study of rare particle physics processes. In order to implement particle identification, light detection can be effectively performed by means of other thermal detectors operated as light sensors. This configuration can be used also in large scale, thousand-channels setups, but the light sensors must be sensitive enough to detect few, possibly a single, photons. The SINGLE project described here aims at producing silicon based, large area devices that can be operated as thermal detectors with single-photon sensitivity, and demonstrate the reliability of the performance, scalability of the production process and integrability with present and next generation cryogenic experiments for the search for rare events.

  5. High brightness single photon sources based on photonic wires

    DEFF Research Database (Denmark)

    Claudon, J.; Bleuse, J.; Bazin, M.

    2009-01-01

    We present a novel single-photon-source based on the emission of a semiconductor quantum dot embedded in a single-mode photonic wire. This geometry ensures a very large coupling (> 95%) of the spontaneous emission to the guided mode. Numerical simulations show that a photon collection efficiency...... of GaAs and defined by reactive-ion etching....

  6. Multi-photon absorption limits to heralded single photon sources

    Science.gov (United States)

    Husko, Chad A.; Clark, Alex S.; Collins, Matthew J.; De Rossi, Alfredo; Combrié, Sylvain; Lehoucq, Gaëlle; Rey, Isabella H.; Krauss, Thomas F.; Xiong, Chunle; Eggleton, Benjamin J.

    2013-01-01

    Single photons are of paramount importance to future quantum technologies, including quantum communication and computation. Nonlinear photonic devices using parametric processes offer a straightforward route to generating photons, however additional nonlinear processes may come into play and interfere with these sources. Here we analyse spontaneous four-wave mixing (SFWM) sources in the presence of multi-photon processes. We conduct experiments in silicon and gallium indium phosphide photonic crystal waveguides which display inherently different nonlinear absorption processes, namely two-photon (TPA) and three-photon absorption (ThPA), respectively. We develop a novel model capturing these diverse effects which is in excellent quantitative agreement with measurements of brightness, coincidence-to-accidental ratio (CAR) and second-order correlation function g(2)(0), showing that TPA imposes an intrinsic limit on heralded single photon sources. We build on these observations to devise a new metric, the quantum utility (QMU), enabling further optimisation of single photon sources. PMID:24186400

  7. CMOS-compatible photonic devices for single-photon generation

    Directory of Open Access Journals (Sweden)

    Xiong Chunle

    2016-09-01

    Full Text Available Sources of single photons are one of the key building blocks for quantum photonic technologies such as quantum secure communication and powerful quantum computing. To bring the proof-of-principle demonstration of these technologies from the laboratory to the real world, complementary metal–oxide–semiconductor (CMOS-compatible photonic chips are highly desirable for photon generation, manipulation, processing and even detection because of their compactness, scalability, robustness, and the potential for integration with electronics. In this paper, we review the development of photonic devices made from materials (e.g., silicon and processes that are compatible with CMOS fabrication facilities for the generation of single photons.

  8. Adenosine myocardial perfusion single-photon emission computed tomography in women compared with men. Impact of diabetes mellitus on incremental prognostic value and effect on patient management.

    Science.gov (United States)

    Berman, Daniel S; Kang, Xingping; Hayes, Sean W; Friedman, John D; Cohen, Ishac; Abidov, Aiden; Shaw, Leslee J; Amanullah, Aman M; Germano, Guido; Hachamovitch, Rory

    2003-04-02

    This study was designed to assess the incremental prognostic value of adenosine stress myocardial perfusion single-photon emission computed tomography (MPS) in women versus men, and to explore the prognostic impact of diabetes mellitus. Limited data are available regarding the incremental value of adenosine stress MPS for the prediction of cardiac death in women versus men and the impact of diabetes mellitus on post-adenosine MPS outcomes. Of 6,173 consecutive patients who underwent rest thallium-201/adenosine technetium-99m sestamibi MPS, 254 (4.1%) were lost to follow-up, and 586 with early revascularization women and 2,677 men. Women had significantly smaller adenosine stress, rest, and reversible defects than men. During 27.0 +/- 8.8 month follow-up, cardiac death rates were lower in women than men (2.0%/year vs. 2.7%/year, respectively, p men and women as a function of MPS results. Multivariable models revealed that MPS results provided incremental prognostic value over pre-scan data for the prediction of cardiac death in both genders. Also, while comparative unadjusted rates of early (women (p men and women. Importantly, diabetic women had a significantly greater risk of cardiac death compared with other patients. Also, after risk adjustment, patients with insulin-dependent diabetes mellitus (IDDM) had higher risk of cardiac death for any MPS result than patients with non-insulin-dependent diabetes mellitus. The findings suggest that adenosine MPS has comparable incremental value for prediction of cardiac death in women and men and that MPS is appropriately influencing subsequent invasive management decisions in both genders. Diabetic women and patients with IDDM appear to have greater risk of cardiac death than other patients for any MPS result.

  9. Myocardial scintigraphy with iodine-123 phenylpentadecanoic acid and thallium-201 in patients with coronary artery disease: a comparative dual-isotope study.

    Science.gov (United States)

    Zimmermann, R; Rauch, B; Kapp, M; Bubeck, B; Neumann, F J; Seitz, F; Stokstad, P; Mall, G; Tillmanns, H; Kübler, W

    1992-01-01

    To characterise the clinical usefulness of serial myocardial scintigraphy with iodine-123 phenylpentadecanoic acid (IPPA) in comparison with thallium-201, dual-isotope investigations were performed in 41 patients with angiographically documented coronary artery disease. Both tracers were administered simultaneously during symptom-limited ergometry. Planar scintigrams were acquired immediately after stress, and delayed imaging was performed after 1 h for IPPA and 4 h for 201Tl. Scintigrams were evaluated both qualitatively and quantitatively using a newly developed algorithm for automated image superposition. Initial myocardial uptake of both tracers was closely correlated (r = 0.75, p or = 75% (IP-PA: 70.0%, 201Tl: 66.3%, P = NS) with identical specificity (69.8%). The number of persistent defects, however, was significantly higher with IPPA (P = 0.021), suggesting that visual analysis of serial IPPA scintigrams may overestimate the presence of myocardial scar tissue. On the other hand, previous Q wave myocardial infarction was associated with a decreased regional IPPA clearance (29% +/- 11% vs 44% +/- 11% in normal myocardium, P IPPA is essentially as sensitive as scintigraphy with 201Tl for the detection of stress-induced perfusion abnormalities. Quantitative analysis of myocardial IPPA kinetics, however, is required for the evaluation of tissue viability.

  10. Myocardial scintigraphy with iodine-123 phenylpentadecanoic acid and thallium-201 in patients with coronary artery disease: A comparative dual-isotope study

    Energy Technology Data Exchange (ETDEWEB)

    Zimmermann, R.; Rauch, B.; Kapp, M.; Neumann, F.J.; Seitz, F.; Kuebler, W. (Heidelberg Univ. (Germany). Dept. of Cardiology); Bubeck, B. (Heidelberg Univ. (Germany). Dept. of Nuclear Medicine); Mall, G. (Heidelberg Univ. (Germany). Dept. of Pathology); Tillmanns, H. (Giessen Univ. (Germany). Dept. of Cardiology); Stokstad, P.

    1992-11-01

    To characterise the clinical usefulness of serial myocardial scintigraphy with iodine-123 phenylpentadecanoic acid (IPPA) in comparison with thallium-201, dual-isotope investigations were performed in 41 patients with angiographically documented coronary artery disease. Both tracers were adminstered simultaneously during symptom-limited ergometry. Planar scintigrams were acquired immediately after stress, and delayed imaging was performed after 1 h for IPPA and 4 h for {sup 201}Tl. Scintigrams were evaluated both qualitatively and quantitatively using a newly developed algorithm for automated image superposition. Initial myocardial uptake of both tracers was closely correlated (r=0.75, p<0.001). Both tracers also revealed a similar sensitivity for the identification of individual coronary artery stenoses {>=}75% (IPPA: 70%, {sup 201}Tl: 66.3%, P=NS) with identical specificity (69.8%). The number of persistent defects, however, was significantly higher with IPPA (P=0.021), suggesting that visual analysis of serial IPPA scintigrams may overestimate the presence of myocardial scar tissue. On the other hand, previous Q wave myocardial infarction was associated with a decreased regional IPPA clearance (29%{+-}11% vs 44%{+-}11% in normal myocardium, P<0.05). The data indicate that serial myocardial scintigraphy with IPPA is essentially as sensitive as scintigraphy with {sup 201}Tl for the detection of stress-induced perfusion abnormalities. Quantitative analysis of myocardial IPPA kinetics, however, is required for the evaluation of tissue viability. (orig.).

  11. Usefulness of thallium-201 myocardial scintigraphy during hyperventilation and accelerated exercise test in patients with vasospastic angina and nearly normal coronary artery

    Energy Technology Data Exchange (ETDEWEB)

    Sueda, Shozo; Mineoi, Kazuaki; Kondou, Tadashi [Takanoko Hospital, Matsuyama, Ehime (Japan)] [and others

    1998-04-01

    The usefulness of thallium-201 ({sup 201}Tl) myocardial scintigraphy was studied in 109 patients with vasospastic angina who had nearly normal coronary arteries (degree of stenosis <50%). Coronary spasm was confirmed by pharmacologic agents in all 109 patients from January 1991 to June 1996. The appearance rate of visual redistribution on {sup 201}Tl myocardial scintigraphy was compared between four groups, 34 patients performing graded bicycle ergometer exercise starting at a work load of 50 W with increments of 25 W every 3 min (Ergo(3) group), 14 patients performing hyperventilation for 5 min (HV(5) group), 31 patients performing bicycle ergometer exercise with increments of 25 W every 1 min after 5 min hyperventilation (HV(5)+Ergo(1) group), and 30 patients at rest (Rest group). The value of the visual redistribution rate on {sup 201}Tl myocardial scintigrams in the HV(5)+Ergo(l) group (65%) was higher than that in the patients of other groups (Ergo(3) 41%, HV(5) 43%, Rest 33%). However, there were no significant differences between the four groups. Stress {sup 201}Tl imaging after hyperventilation and accelerated exercise is useful to disclose ischemic evidence in about two thirds of patients with vasospastic angina and nearly normal coronary arteries, whereas about 40% of patients had visual redistribution on {sup 201}Tl myocardial scintigrams by performing standard procedures. (author)

  12. Serial thallium-201 imaging at rest in patients with unstable and stable angina pectoris: relationship of myocardial perfusion at rest to presenting clinical syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Brown, K.A.; Okada, R.D.; Boucher, C.A.; Phillips, H.R.; Strauss, H.W.; Pohost, G.M.

    1983-07-01

    In order to determine whether there are differences in myocardial perfusion at rest among patients with various unstable and stable angina syndromes, serial thallium-201 imaging was performed at rest in 19 patients presenting with rapidly worsening exertional angina (unstable angina, group A), 12 patients with rest angina alone without exertional symptoms (unstable angina, group B), and 34 patients with chronic stable angina. No patient had an episode of angina within 4 hours of study. Nineteen of 19 (100%) patients in group A demonstrated transient defects compared to only 3 of 12 (25%) patients in group B (p less than 0.0001) and 4 of 34 (12%) stable angina patients (p less than 0.0001). The majority of zones demonstrating transient defects in group A were associated with hypokinesis of the corresponding left ventriculogram segment without associated ECG evidence of previous infarction. There were no significant differences in the frequency of persistent thallium defects, severity of angiographic coronary artery disease, or frequency of regional wall motion abnormalities of myocardial segments supplied by stenotic coronary arteries among the three groups of patients. Transient defects have been shown to reflect reduction in regional coronary blood flow to viable myocardium. Therefore, we conclude that regional resting hypoperfusion of viable myocardium is far more common in patients with exertional unstable angina symptoms than in patients with rest angina alone or chronic stable angina.

  13. Diagnostic value of 123I-phenylpentadecanoic acid (IPPA) metabolic and thallium 201 perfusion imaging in stable coronary artery disease.

    Science.gov (United States)

    Walamies, M; Turjanmaa, V; Koskinen, M; Uusitalo, A

    1993-08-01

    The diagnostic value of 123I-phenylpentadecanoic acid (IPPA) metabolic cardiac imaging was studied in a group (n = 29) of patients with angiographically confirmed CAD using single photon emission computed tomography (SPECT). A symptom-limited exercise test was first done with IPPA, and 2 days later with thallium. Medications were not withheld during testing. Fourteen healthy control subjects participated in parallel IPPA and 15 in thallium tests. Data acquisition and output were comparable in the two imaging modalities. By testing various relatively simple criteria for abnormality we found that the semiquantitative interpretation was more accurate than the visual readings. The best compromise of accuracy with the scored criteria consisted of a sensitivity of 86% and a specificity of 86%, obtained with IPPA polar tomograms (mild exercise defect) and a sensitivity of 86% and a specificity of 80% obtained with thallium (regionally decreased washout). With visual interpretation alone, a sensitivity of 83% and a specificity of 71% was detected with IPPA (mild exercise defect) and 72% and 73%, respectively, with thallium (partial reversibility). The sensitivity of the exercise ECG alone was 62%. The results of this study imply that IPPA imaging could be a rational, uncomplicated clinical method for non-invasive diagnosis of CAD. The diagnostic ability of IPPA is at least as good as that of thallium, and it is possible to use them in succession.

  14. Assessment of myocardial viability by dynamic tomographic iodine 123 iodophenylpentadecanoic acid imaging: comparison with rest-redistribution thallium 201 imaging.

    Science.gov (United States)

    Iskandrian, A S; Powers, J; Cave, V; Wasserleben, V; Cassell, D; Heo, J

    1995-01-01

    This study examined the ability of dynamic 123I-labeled iodophenylpentadecanoic acid (IPPA) imaging to detect myocardial viability in patients with left ventricular (LV) dysfunction caused by coronary artery disease. Serial 180-degree single-photon emission computed tomographic (SPECT) images (five sets, 8 minutes each) were obtained starting 4 minutes after injection of 2 to 6 mCi 123I at rest in 21 patients with LV dysfunction (ejection fraction [EF] 34% +/- 11%). The segmental uptake was compared with that of rest-redistribution 201Tl images (20 segments/study). The number of perfusion defects (reversible and fixed) was similar by IPPA and thallium (11 +/- 5 vs 10 +/- 5 segments/patient; difference not significant). There was agreement between IPPA and thallium for presence or absence (kappa = 0.78 +/- 0.03) and nature (reversible, mild fixed, or severe fixed) of perfusion defects (kappa = 0.54 +/- 0.04). However, there were more reversible IPPA defects than reversible thallium defects (7 +/- 4 vs 3 +/- 4 segments/patient; p = 0.001). In 14 patients the EF (by gated pool imaging) improved after coronary revascularization from 33% +/- 11% to 39% +/- 12% (p = 0.002). The number of reversible IPPA defects was greater in the seven patients who had improvement in EF than in the patients without such improvement (10 +/- 4 vs 5 +/- 4 segments/patient; p = 0.075). 123I-labeled IPPA SPECT imaging is a promising new technique for assessment of viability. Reversible defects predict recovery of LV dysfunction after coronary revascularization.

  15. Assessment of the effect of revascularization early after CABG using ECG-gated perfusion single-photon emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kubo, Shigeto; Tadamura, Eiji; Kudoh, Takashi; Inubushi, Masayuki; Konishi, Junji [Dept. of Nuclear Medicine and Diagnostic Imaging, Kyoto University Graduate (Japan); Ikeda, Tadashi; Koshiji, Takaaki; Nishimura, Kazunobu; Komeda, Masashi [Dept. of Cardiovascular Surgery, Kyoto University (Japan); Tamaki, Nagara [Dept. of Nuclear Medicine, Hokkaido University, Sapporo (Japan)

    2001-02-01

    When an arterial graft is used, reversible perfusion defects on single-photon emission tomography (SPET) perfusion images are occasionally observed early after coronary artery bypass graft surgery (CABG), owing to the restricted flow capacity. The purpose of this study was to determine whether the functional information obtained with electrocardiography (ECG)-gated perfusion SPET could be helpful in evaluating the effect of revascularization early after CABG. Twenty-three patients (18 men and 5 women, mean age 65{+-}9 years) underwent stress/re-injection thallium-201 ECG-gated SPET before and 4 weeks after CABG (13 with exercise and 10 with dipyridamole). Patency of all grafts was confirmed by coronary angiography 1 month after CABG. Cardiac functional data including the left ventricular ejection fraction (LVEF) and the transient ischaemic dilatation (TID) ratio were analysed using a commercially available automated program. The conventional stress and re-injection tomograms were interpreted by means of a five-point scoring system in a nine-segment model. Stress-induced reversible {sup 201}Tl perfusion defects were present in 64% of the myocardial segments bypassed by patent arterial grafts, in contrast to 42% of the myocardial segments bypassed by patent venous grafts ({chi}{sup 2}=7.8, P=0.005). Of the 23 patients, 12 showed improvement in summed ischaemic scores (group 1), while 11 had no change or deterioration (group 2), although all grafts were patent on postoperative catheterization. The TID ratio improved in both group 1 and group 2 before and after CABG (1.14{+-}0.13 vs 0.99{+-}0.07, P=0.001 and 1.09{+-}0.07 vs 0.94{+-}0.05, P=0.002, respectively). However, LVEF did not significantly improve in group 1 or group 2 after CABG (42.5%{+-}9.9% vs 47.5%{+-}11.8%, and 52.1%{+-}7.5% vs 53.1%{+-}5.9%, respectively). Perfusion imaging or LVEF assessment is of limited value early after CABG. The TID ratio obtained with ECG-gated perfusion SPET may be a useful marker

  16. Highly efficient sources of single indistinguishable photons

    DEFF Research Database (Denmark)

    Gregersen, Niels

    2013-01-01

    Solid-state sources capable of emitting single photons on demand are of great interest in quantum information applications. Ideally, such a source should emit exactly one photon into the collection optics per trigger, the emitted photons should be indistinguishable and the source should...

  17. Simultaneous dual myocardial imaging with iodine-123-[beta]-methyl iodophenyl-pentadecanoic acid (BMIPP) and thallium-201 in patients with coronary heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Tawarahara, Kei; Kurata, Chinori; Taguchi, Takahisa; Aoshima, Shigeyuki; Okayama, Kenichi; Kobayashi, Akira; Yamazaki, Noboru; Kaneko, Masao (Hamamatsu Univ. School of Medicine, Shizuoka (Japan))

    1994-02-01

    To assess the clinical value of simultaneous dual myocardial imaging with iodine-123-[beta]-methyl-iodophenyl-pentadecanoic acid ([sup 123]I-BMIPP) and thallium-201 ([sup 201]TL), myocardial imaging was performed at rest and during execise in seven patients with coronary heart disease. When [sup 123]I-BMIPP and [sup 201]Tl images were compared, the initial exercise and resting images agreed 87% and 64%, respectively. In the initial resting images, the regional uptake of [sup 123]I-BMIPP was frequently less than that of [sup 201]Tl. The incidence of exercise-induced reversible defects by [sup 201]Tl in the Tl>BMIPP regions was significantly higher than that in the Tl=BMIPP regions (57% vs 4%, p<0.01) and the incidence of coronary narrowing of more than 90% in the Tl>BMIPP regions was also significantly higher than that in the Tl=BMIPP regions (91% vs 38%, p<0.01). In addition, this disparity (Tl>BMIPP) was found more frequently in regions with abnormal wall motion than in regions with normal wall motion (hypokinetic regions; 68%, severe hypokinetic or akinetic regions; 50%, vs normokinetic regions; 4%, p<0.01). In contrast, the uptake of [sup 123]I-BMIPP correlated closely with that of [sup 201]Tl in normal myocardium and the uptake of both [sup 123]I-BMIPP and [sup 201]Tl was severely reduced in myocardium with severe ischemia during exercise and prior infarction. These results indicate that dual myocardial imaging with [sup 123]I-BMIPP and [sup 201]Tl may provide a unique means of identifying patients with metabolically disturbed myocardium, such as hibernating and stunned myocardium. (author).

  18. Photon correlation in single-photon frequency upconversion.

    Science.gov (United States)

    Gu, Xiaorong; Huang, Kun; Pan, Haifeng; Wu, E; Zeng, Heping

    2012-01-30

    We experimentally investigated the intensity cross-correlation between the upconverted photons and the unconverted photons in the single-photon frequency upconversion process with multi-longitudinal mode pump and signal sources. In theoretical analysis, with this multi-longitudinal mode of both signal and pump sources system, the properties of the signal photons could also be maintained as in the single-mode frequency upconversion system. Experimentally, based on the conversion efficiency of 80.5%, the joint probability of simultaneously detecting at upconverted and unconverted photons showed an anti-correlation as a function of conversion efficiency which indicated the upconverted photons were one-to-one from the signal photons. While due to the coherent state of the signal photons, the intensity cross-correlation function g(2)(0) was shown to be equal to unity at any conversion efficiency, agreeing with the theoretical prediction. This study will benefit the high-speed wavelength-tunable quantum state translation or photonic quantum interface together with the mature frequency tuning or longitudinal mode selection techniques.

  19. Integrated optomechanical single-photon frequency shifter

    Science.gov (United States)

    Fan, Linran; Zou, Chang-Ling; Poot, Menno; Cheng, Risheng; Guo, Xiang; Han, Xu; Tang, Hong X.

    2016-12-01

    The ability to manipulate single photons is of critical importance for fundamental quantum optics studies and practical implementations of quantum communications. While extraordinary progresses have been made in controlling spatial, temporal, spin and orbit angular momentum degrees of freedom, frequency-domain control of single photons so far relies on nonlinear optical effects, which have faced obstacles such as noise photons, narrow bandwidth and demanding optical filtering. Here, we demonstrate the first integrated optomechanical single-photon frequency shifter with near-unity efficiency. A frequency shift up to 150 GHz at telecom wavelength is realized without measurable added noise and the preservation of quantum coherence is verified through quantum interference between twin photons of different colours. This single-photon frequency shifter will be invaluable for increasing the channel capacity of quantum communications and compensating frequency mismatch between quantum systems, paving the road towards a hybrid quantum network.

  20. Phase estimation with squeezed single photons

    Directory of Open Access Journals (Sweden)

    Olivares Stefano

    2016-01-01

    Full Text Available We address the performance of an interferometric setup in which a squeezed single photon interferes at a beam splitter with a coherent state. Our analysis in based on both the quantum Fisher information and the sensitivity when a Mach-Zehnder setup is considered and the difference photocurrent is detected at the output. We compare our results with those obtained feeding the interferometer with a squeezed vacuum (with the same squeezing parameter of the squeezed single photon and a coherent state in order to have the same total number of photons circulating in the interferometer. We find that for fixed squeezing parameter and total number of photons there is a threshold of the coherent amplitude interfering with the squeezed single photon above which the squeezed single photons outperform the performance of squeezed vacuum (showing the highest quantum Fisher information. When the difference photocurrent measurement is considered, we can always find a threshold of the squeezing parameter (given the total number of photons and the coherent amplitude above which squeezed single photons can be exploited to reach a better sensitivity with respect to the use of squeezed vacuum states also in the presence of non unit quantum efficiency.

  1. Relative value of thallium-201 and iodine-131 scans in the detection of recurrence or distant metastasis of well differentiated thyroid carcinoma.

    Science.gov (United States)

    Lin, J D; Kao, P F; Weng, H F; Lu, W T; Huang, M J

    1998-07-01

    Radioactive iodine (131I) has been found to be more sensitive and more specific than thallium-201 for the detection of distant metastases and thyroid remnants in the neck in cases of well-differentiated thyroid carcinoma. 201Tl has been deemed particularly useful in localizing metastases or recurrence in patients with a negative 131I scan and abnormal levels of serum thyroglobulin (Tg). This study aimed to: (1) determine the value of 201Tl imaging in localizing metastases or recurrence in patients with well-differentiated thyroid carcinoma, and (2) evaluate the false-positive and false-negative results of 131I and 201Tl scintigraphy. Sixty-two thyroid remnant ablated patients who underwent simultaneous postoperative 201Tl and 131I scans and and serum Tg determinations were evaluated. Fifty patients had papillary thyroid carcinomas and 12 had follicular thyroid carcinomas. 201Tl imaging was performed before the 131I studies. Of the 62 patients who underwent 201Tl imaging studies, 24 were found to have positive results, with local recurrence or distant metastases. Patients with positive results in the 201Tl imaging studies tended to be older, were mor often male, had higher Tg levels and had a higher recurrence rate. Of these 24 patients, ten had negative diagnostic or therapeutic 131I scans. Concurrently, serum Tg levels were less than 5 ng/ml in five of these ten patients. Three patients were deemed false positive by 201Tl scans; one had a parotid tumour, one a periodontal abscess and one lung metastasis. Among the 38 patients with negative 201Tl scans, 11 had positive findings on 131I scans. Three had distant metastases: two with lung metastases and one with bone metastases. Patients with false-positive results on 131I scans included those with biliary tract stones, ovarian cysts, and breast secretion. Of the 27 patients with negative 201Tl and 131I scans, 15 had elevated serum Tg levels. Among these, local recurrence followed by lung metastases was manifested in

  2. Relative value of thallium-201 and iodine-131 scans in the detection of recurrence or distant metastasis of well differentiated thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Lin Jen-Der; Weng Hsiao-Fen; Lu Wen-Tsoung [Division of Endocrinology and Metabolism, Chang Gung Memorial Hospital (Taiwan, Province of China); Kao Pan-Fu; Huang Miau-Ju [Department of Nuclear Medicine, Chang Gung Memorial Hospital, Taiwan (Taiwan, Province of China)

    1998-07-01

    Radioactive iodine ({sup 131}I) has been found to be more sensitive and more specific than thallium-201 for the detection of distant metastases and thyroid remnants in the neck in cases of well-differentiated thyroid carcinoma. {sup 201}Tl has been deemed particularly useful in localizing metastases or recurrence in patients with a negative {sup 131}I scan and abnormal levels of serum thyroglobulin (Tg). This study aimed to: (1) determine the value of {sup 201}Tl imaging in localizing metastases or recurrence in patients with well-differentiated thyroid carcinoma, and (2) evaluate the false-positive and false-negative results of {sup 131}I and {sup 201}Tl scintigraphy. Sixty-two thyroid remnant ablated patients who underwent simultaneous postoperative {sup 201}Tl and {sup 131}I scans and and serum Tg determinations were evaluated. Fifty patients had papillary thyroid carcinomas and 12 had follicular thyroid carcinomas. {sup 201}Tl imaging was performed before the {sup 131}I studies. Of the 62 patients who underwent {sup 201}Tl imaging studies, 24 were found to have positive results, with local recurrence or distant metastases. Patients with positive results in the {sup 201}Tl imaging studies tended to be older, were mor often male, had higher Tg levels and had a higher recurrence rate. Of these 24 patients, ten had negative diagnostic or therapeutic {sup 131}I scans. Concurrently, serum Tg levels were less than 5 ng/ml in five of these ten patients. Three patients were deemed false positive by {sup 201}Tl scans; one had a parotid tumour, one a periodontal abscess and one lung metastasis. Among the 38 patients with negative {sup 201}Tl scans, 11 had positive findings on {sup 131}I scans. Three had distant metastases: two with lung metastases and one with bone metastases. Patients with false-positive results on {sup 131}I scans included those with biliary tract stones, ovarian cysts, and breast secretion. Of the 27 patients with negative {sup 201}Tl and {sup 131}I

  3. Computational Modeling of Photonic Crystal Microcavity Single-Photon Emitters

    Science.gov (United States)

    Saulnier, Nicole A.

    Conventional cryptography is based on algorithms that are mathematically complex and difficult to solve, such as factoring large numbers. The advent of a quantum computer would render these schemes useless. As scientists work to develop a quantum computer, cryptographers are developing new schemes for unconditionally secure cryptography. Quantum key distribution has emerged as one of the potential replacements of classical cryptography. It relics on the fact that measurement of a quantum bit changes the state of the bit and undetected eavesdropping is impossible. Single polarized photons can be used as the quantum bits, such that a quantum system would in some ways mirror the classical communication scheme. The quantum key distribution system would include components that create, transmit and detect single polarized photons. The focus of this work is on the development of an efficient single-photon source. This source is comprised of a single quantum dot inside of a photonic crystal microcavity. To better understand the physics behind the device, a computational model is developed. The model uses Finite-Difference Time-Domain methods to analyze the electromagnetic field distribution in photonic crystal microcavities. It uses an 8-band k · p perturbation theory to compute the energy band structure of the epitaxially grown quantum dots. We discuss a method that combines the results of these two calculations for determining the spontaneous emission lifetime of a quantum dot in bulk material or in a microcavity. The computational models developed in this thesis are used to identify and characterize microcavities for potential use in a single-photon source. The computational tools developed are also used to investigate novel photonic crystal microcavities that incorporate 1D distributed Bragg reflectors for vertical confinement. It is found that the spontaneous emission enhancement in the quasi-3D cavities can be significantly greater than in traditional suspended slab

  4. Extending single-photon optimized superconducting transition edge sensors beyond the single-photon counting regime.

    Science.gov (United States)

    Gerrits, Thomas; Calkins, Brice; Tomlin, Nathan; Lita, Adriana E; Migdall, Alan; Mirin, Richard; Nam, Sae Woo

    2012-10-08

    Typically, transition edge sensors resolve photon number of up to 10 or 20 photons, depending on the wavelength and TES design. We extend that dynamic range up to 1000 photons, while maintaining sub-shot noise detection process uncertainty of the number of detected photons and beyond that show a monotonic response up to ≈ 6 · 10(6) photons in a single light pulse. This mode of operation, which heats the sensor far beyond its transition edge into the normal conductive regime, offers a technique for connecting single-photon-counting measurements to radiant-power measurements at picowatt levels. Connecting these two usually incompatible operating regimes in a single detector offers significant potential for directly tying photon counting measurements to conventional cryogenic radiometric standards. In addition, our measurements highlight the advantages of a photon-number state source over a coherent pulse source as a tool for characterizing such a detector.

  5. Changing optical band structure with single photons

    Science.gov (United States)

    Albrecht, Andreas; Caneva, Tommaso; Chang, Darrick E.

    2017-11-01

    Achieving strong interactions between individual photons enables a wide variety of exciting possibilities in quantum information science and many-body physics. Cold atoms interfaced with nanophotonic structures have emerged as a platform to realize novel forms of nonlinear interactions. In particular, when atoms are coupled to a photonic crystal waveguide, long-range atomic interactions can arise that are mediated by localized atom-photon bound states. We theoretically show that in such a system, the absorption of a single photon can change the band structure for a subsequent photon. This occurs because the first photon affects the atoms in the chain in an alternating fashion, thus leading to an effective period doubling of the system and a new optical band structure for the composite atom-nanophotonic system. We demonstrate how this mechanism can be engineered to realize a single-photon switch, where the first incoming photon switches the system from being highly transmissive to highly reflective, and analyze how signatures can be observed via non-classical correlations of the outgoing photon field.

  6. Quantum identity authentication with single photon

    Science.gov (United States)

    Hong, Chang ho; Heo, Jino; Jang, Jin Gak; Kwon, Daesung

    2017-10-01

    Quantum identity authentication with single photons is proposed in the paper. It can verify a user's identity without exposing to an authentication key information. The protocol guarantees high efficiency in that it can verify two bits of authentication information using just a single photon. The security of our authentication scheme is analyzed and confirmed in the case of a general attack. Moreover, the proposed protocol is practicable with current technology. Our quantum identity authentication protocol does not require quantum memory registration and any entangled photon sources.

  7. Single-photon manipulation in Nanophotonic Circuits

    DEFF Research Database (Denmark)

    Hansen, Sofie Lindskov

    Quantum dots in photonic nanostructures has long been known to be a very powerful and versatile solid-state platform for conducting quantum optics experiments. The present PhD thesis describes experimental demonstrations of single-photon generation and subsequent manipulation all realized...... be realized on a chip with embedded quantum dots. This allows for on-chip generation and manipulation of single photons. The router consists of an on-chip interferometer where the phase difference between the arms of the interferometer is controlled electrically. The response time of the device...

  8. Photonic wires and trumpets for ultrabright single photon sources

    DEFF Research Database (Denmark)

    Gérard, Jean-Michel; Claudon, Julien; Bleuse, Joël

    2013-01-01

    as to tailor their radiation diagram in the far-field. We highlight the novel “photonic trumpet” geometry, which provides a clean Gaussian beam, and is much less sensitive to fabrication imperfections than the more common needle-like taper geometry. S4Ps based on a single QD in a PW with integrated bottom...

  9. Single photon detector design features

    Science.gov (United States)

    Zaitsev, Sergey V.; Kurochkin, Vladimir L.; Kurochkin, Yury V.

    2016-12-01

    In the report are discussed the laboratory test results of SPAD detectors with InGaAs / InP avalanche photodiodes, operating in Geiger mode. Device operating in synchronous mode with the dead timer setting for proper working conditions of photodiodes. The report materials will showing the functional block diagram of the detector, real operating signals in the receiver path and clock circuits and main results of measurements. The input signal of the synchronous detector is the clock, which determines the time positions of expected photons arrival. Increasing the clock speed 1-300 MHz or getting more time positions of the time grid, we provide increased capacity for time position code of signals, when QKD information transmitted over the nets. At the same time, the maximum attainable speed of photon reception is limited by diode dead time. Diode quantum noise are minimized by inclusion of a special time interval - dead time 0.1-10 usec, after each received and registered a photon. The lowest attainable value of the dead time is determined as a compromise between transients in electrical circuits, passive avalanche «quenching» circuit and thermal transients cooling crystal diode, after each avalanche pass though photodiode. Achievable time and speed parameters are discussed with specific examples of detectors.

  10. Global Algorithm Applied on Single Photon Detection

    Science.gov (United States)

    LIU, Hua; DING, Quanxin; Wang, Helong; Chen, Hongliang; GUO, Chunjie; ZHOU, Liwei

    2017-06-01

    There are three major contributions. Firstly, applied study on the theory and experiment of single photon detection, including the project and experiment of quantum key distribution. Secondly, based on methods of the selection of detector, main photo electronic system configuration, design and creation, along with the relationship between these to system characteristics have been studied. Thirdly, based on the considerations on the research of image sensor systems on single photon detection, and the total system characteristics are evaluated and discussed in quantity. The results of simulation experiments and theory analyzing demonstrate that proposed method could advance the system validity effectively, and theory analysis and experiment shows the method is reasonable and efficient.

  11. Recent Advances for High-Efficiency Sources of Single Photons Based on Photonic Nanowires

    DEFF Research Database (Denmark)

    Gerard, J. M.; Claudon, J.; Munsch, M.

    2012-01-01

    Photonic nanowires have recently been used to tailor the spontaneous emission of embedded quantum dots, and to develop record efficiency single-photon sources. We will present recent developments in this field mainly 1) the observation of a strong inhibition of the spontaneous emission of quantum...... dots in ultrathin photonic wires 2) the control of the linear polarization of the single photons by photonic wires with an elliptical section, 3) the joint observation (unlike-cavity-based devices) of a record high efficiency and pure single photon emission process in a photonic wire single photon...

  12. Interactive Screen Experiments with Single Photons

    Science.gov (United States)

    Bronner, Patrick; Strunz, Andreas; Silberhorn, Christine; Meyn, Jan-Peter

    2009-01-01

    Single photons are used for fundamental quantum physics experiments as well as for applications. Originally being a topic of advance courses, such experiments are increasingly a subject of undergraduate courses. We provide interactive screen experiments (ISE) for supporting the work in a real laboratory, and for students who do not have access to…

  13. Single Photon Experiments and Quantum Complementarity

    Directory of Open Access Journals (Sweden)

    Georgiev D. D.

    2007-04-01

    Full Text Available Single photon experiments have been used as one of the most striking illustrations of the apparently nonclassical nature of the quantum world. In this review we examine the mathematical basis of the principle of complementarity and explain why the Englert-Greenberger duality relation is not violated in the configurations of Unruh and of Afshar.

  14. Ultrafast time measurements by time-correlated single photon counting coupled with superconducting single photon detector

    Energy Technology Data Exchange (ETDEWEB)

    Shcheslavskiy, V., E-mail: vis@becker-hickl.de; Becker, W. [Becker & Hickl GmbH, Nahmitzer Damm 30, 12277 Berlin (Germany); Morozov, P.; Divochiy, A. [Scontel, Rossolimo St., 5/22-1, Moscow 119021 (Russian Federation); Vakhtomin, Yu. [Scontel, Rossolimo St., 5/22-1, Moscow 119021 (Russian Federation); Moscow State Pedagogical University, 1/1 M. Pirogovskaya St., Moscow 119991 (Russian Federation); Smirnov, K. [Scontel, Rossolimo St., 5/22-1, Moscow 119021 (Russian Federation); Moscow State Pedagogical University, 1/1 M. Pirogovskaya St., Moscow 119991 (Russian Federation); National Research University Higher School of Economics, 20 Myasnitskaya St., Moscow 101000 (Russian Federation)

    2016-05-15

    Time resolution is one of the main characteristics of the single photon detectors besides quantum efficiency and dark count rate. We demonstrate here an ultrafast time-correlated single photon counting (TCSPC) setup consisting of a newly developed single photon counting board SPC-150NX and a superconducting NbN single photon detector with a sensitive area of 7 × 7 μm. The combination delivers a record instrument response function with a full width at half maximum of 17.8 ps and system quantum efficiency ∼15% at wavelength of 1560 nm. A calculation of the root mean square value of the timing jitter for channels with counts more than 1% of the peak value yielded about 7.6 ps. The setup has also good timing stability of the detector–TCSPC board.

  15. Single-Photon Technologies Based on Quantum-Dots in Photonic Crystals

    DEFF Research Database (Denmark)

    Lehmann, Tau Bernstorff

    -photon purity under quasi-resonantexcitation. Furthermore the waveguide based platform demonstrates indistinguishable single-photonsat timescales up to 13 ns.A setup for active demultiplexing of single-photons to a three-fold single-photon state is proposed.Using a fast electro-optical modulator, single...

  16. Single Photon Thermal Ionization of C60

    Science.gov (United States)

    Hansen, Klavs; Richter, Robert; Alagia, Michele; Stranges, Stefano; Schio, Luca; Salén, Peter; Yatsyna, Vasyl; Feifel, Raimund; Zhaunerchyk, Vitali

    2017-03-01

    We report on experiments which show that C60 can ionize in an indirect, quasithermal boiloff process after absorption of a single photon. The process involves a large number of incoherently excited valence electrons and yields electron spectra with a Boltzmann distribution with temperatures exceeding 104 K . It is expected to be present for other molecules and clusters with a comparatively large number of valence electrons. The astrophysical consequences are briefly discussed.

  17. Single-Photon Technologies Based on Quantum-Dots in Photonic Crystals

    DEFF Research Database (Denmark)

    Lehmann, Tau Bernstorff

    In this thesis, the application of semiconductor quantum-dots in photonic crystals is explored as aresource for single-photon technology.Two platforms based on photonic crystals, a cavity and a waveguide, are examined as platformssingle-photon sources. Both platforms demonstrate strong single......-photons from a quantum-dot are routed on timescalesof the exciton lifetime. Using active demultiplexing a three-fold single-photon state is generated at anextracted rate of 2:03 ±0:49 Hz.An on-chip power divider integrated with a quantum-dot is investigated. Correlation measurementof the photon statistic...... veries the single-photon nature of the quantum-dot. Furthermore correlationmeasurement between the outputs of the power divider conrms the passive separation of the singlephotonemission.A scheme for post-emission entanglement generation between single-photons from an efficientsource is discussed...

  18. Pushing the limits of single-photon information encoding

    NARCIS (Netherlands)

    Hummel, T.; Tentrup, Tristan Bernhard Horst; Uppu, Ravitej; Mosk, Allard; Pinkse, Pepijn Willemszoon Harry

    2016-01-01

    Single photons are the carrier of choice in many quantum information processing protocols. Encoding information in a high-dimensional Hilbert space allows for the transfer of more than one bit of information per photon. We use a spatial light modulator (SLM) to direct the single photons to distinct

  19. Dead Time of Single Photon Avalanche Diodes

    Energy Technology Data Exchange (ETDEWEB)

    Neri, L., E-mail: lorenzo.neri@ct.infn.it [INFN Laboratori Nazionali del Sud, via S.Sofia 62, I-95125, Catania (Italy); Universita degli Studi di Catania, via S.Sofia 64, I-95123, Catania (Italy); Tudisco, S. [INFN Laboratori Nazionali del Sud, via S.Sofia 62, I-95125, Catania (Italy); Musumeci, F.; Scordino, A. [Universita degli Studi di Catania, via S.Sofia 64, I-95123, Catania (Italy); Fallica, G.; Mazzillo, M. [ST-Microelectronics, stradale Primosole 50, I-95100, Catania (Italy); Zimbone, M. [Universita degli Studi di Catania, via S.Sofia 64, I-95123, Catania (Italy)

    2011-06-15

    Single Photon Avalanche Diode (SPAD) is the new generation of Geiger-Muller counter device developed in semiconductor technology [S. Privitera et al. Sensors Journal, vol 8 Iss. 8 (2008) 4636; S. Tudisco et al. IEEE Sensors Journal vol 8 ISS 7-8 (2008) 1324; S. Cova et al. Applied Optics 35 (1996) 1956]. Physical dead time model and noise production process has been analyzed and their corrections have been performed [S.H. Lee, R.P. Gardner, M. Jae, Nucl. Instr. and Meth. in Phys. Res. B 263 (2007) 46]. We have been able to extract the real amount of incident photon rate up to 10{sup 7}cps using a device with 0.97{mu}s total deadtime. We also developed the equation of the noise count rate vs incoming photon rate, supported by Montecarlo simulation and experimental data. We marked the difference between dark rate and noise count rate, and introduced the noise rate inside the hybrid deadtime equation used for SPAD device.

  20. Spectral compression of single-photon-level laser pulse

    Science.gov (United States)

    Li, Yuanhua; Xiang, Tong; Nie, Yiyou; Sang, Minghuang; Chen, Xianfeng

    2017-02-01

    We experimentally demonstrate that the bandwidth of single photons laser pulse is compressed by a factor of 58 in a periodically poled lithium niobate (PPLN) waveguide chip. A positively chirped single photons laser pulse and a negatively chirped classical laser pulse are employed to produce a narrowband single photon pulse with new frequency through sum-frequency generation. In our experiment, the frequency and bandwidth of single photons at 1550 nm are simultaneously converted. Our results mark a critical step towards the realization of coherent photonic interface between quantum communication at 1550 nm and quantum memory in the near-visible window.

  1. Coupling of single quantum dots to a photonic crystal waveguide

    DEFF Research Database (Denmark)

    Lund-Hansen, Toke; Stobbe, Søren; Julsgaard, Brian

    is coupled efficiently to a single enhanced mode. One popular approach has been to couple single quantum dots to a nanocavity but a limiting factor in this configuration is that in order to apply the photon it should subsequently be coupled out of the cavity, reducing the overall efficiency significantly....... An alternative approach is to couple the quantum dot directly to the propagating mode of a photonic waveguide. We demonstrate the coupling of single quantum dots to a photonic crystal waveguide using time-resolved spontaneous emission measurements. A pronounced effect is seen in the decay rates of dots coupled......Efficient and high quality single-photon sources is a key element in quantum information processing using photons. As a consequence, much current research is focused on realizing all-solid-state nanophotonic single-photon sources. Single photons can be harvested with high efficiency if the emitter...

  2. Quantum optics. All-optical routing of single photons by a one-atom switch controlled by a single photon.

    Science.gov (United States)

    Shomroni, Itay; Rosenblum, Serge; Lovsky, Yulia; Bechler, Orel; Guendelman, Gabriel; Dayan, Barak

    2014-08-22

    The prospect of quantum networks, in which quantum information is carried by single photons in photonic circuits, has long been the driving force behind the effort to achieve all-optical routing of single photons. We realized a single-photon-activated switch capable of routing a photon from any of its two inputs to any of its two outputs. Our device is based on a single atom coupled to a fiber-coupled, chip-based microresonator. A single reflected control photon toggles the switch from high reflection (R ~ 65%) to high transmission (T ~ 90%), with an average of ~1.5 control photons per switching event (~3, including linear losses). No additional control fields are required. The control and target photons are both in-fiber and practically identical, making this scheme compatible with scalable architectures for quantum information processing. Copyright © 2014, American Association for the Advancement of Science.

  3. Nanofabrication of Plasmonic Circuits Containing Single Photon Sources

    OpenAIRE

    Siampour, Hamidreza; Kumar, Shailesh; Bozhevolnyi, Sergey I.

    2017-01-01

    Nanofabrication of photonic components based on dielectric-loaded surface plasmon-polariton waveguides (DLSPPWs) excited by single nitrogen vacancy (NV) centers in nanodiamonds is demonstrated. DLSPPW circuits are built around NV containing nanodiamonds, which are certified to be single-photon emitters, using electron-beam lithography of hydrogen silsesquioxane (HSQ) resist on silver-coated silicon substrates. A propagation length of ~20 {\\mu}m for the NV single-photon emission is measured wi...

  4. Waveguide-Coupled Superconducting Nanowire Single-Photon Detectors

    Science.gov (United States)

    Beyer, Andrew D.; Briggs, Ryan M.; Marsili, Francesco; Cohen, Justin D.; Meenehan, Sean M.; Painter, Oskar J.; Shaw, Matthew D.

    2015-01-01

    We have demonstrated WSi-based superconducting nanowire single-photon detectors coupled to SiNx waveguides with integrated ring resonators. This photonics platform enables the implementation of robust and efficient photon-counting detectors with fine spectral resolution near 1550 nm.

  5. Single-photon source engineering using a Modal Method

    DEFF Research Database (Denmark)

    Gregersen, Niels

    Solid-state sources of single indistinguishable photons are of great interest for quantum information applications. The semiconductor quantum dot embedded in a host material represents an attractive platform to realize such a single-photon source (SPS). A near-unity efficiency, defined as the num......Solid-state sources of single indistinguishable photons are of great interest for quantum information applications. The semiconductor quantum dot embedded in a host material represents an attractive platform to realize such a single-photon source (SPS). A near-unity efficiency, defined...

  6. The photonic nanowire: A highly efficient single-photon source

    DEFF Research Database (Denmark)

    Gregersen, Niels

    2014-01-01

    The photonic nanowire represents an attractive platform for a quantum light emitter. However, careful optical engineering using the modal method, which elegantly allows access to all relevant physical parameters, is crucial to ensure high efficiency.......The photonic nanowire represents an attractive platform for a quantum light emitter. However, careful optical engineering using the modal method, which elegantly allows access to all relevant physical parameters, is crucial to ensure high efficiency....

  7. A high-efficiency electrically-pumped single-photon source based on a photonics nanowire

    DEFF Research Database (Denmark)

    Gregersen, Niels; Nielsen, Torben Roland; Mørk, Jesper

    An electrically-pumped single-photon source design with a predicted efficiency of 89% is proposed. The design is based on a quantum dot embedded in a photonic nanowire with tailored ends and optimized contact electrodes. Unlike cavity-based approaches, the photonic nanowire features broadband...

  8. Quantum Probability Cancellation Due to a Single-Photon State

    Science.gov (United States)

    Ou, Z. Y.

    1996-01-01

    When an N-photon state enters a lossless symmetric beamsplitter from one input port, the photon distribution for the two output ports has the form of Bernouli Binormial, with highest probability at equal partition (N/2 at one outport and N/2 at the other). However, injection of a single photon state at the other input port can dramatically change the photon distribution at the outputs, resulting in zero probability at equal partition. Such a strong deviation from classical particle theory stems from quantum probability amplitude cancellation. The effect persists even if the N-photon state is replaced by an arbitrary state of light. A special case is the coherent state which corresponds to homodyne detection of a single photon state and can lead to the measurement of the wave function of a single photon state.

  9. Direct fiber-coupled single photon source based on a photonic crystal waveguide

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Byeong-Hyeon, E-mail: seygene@kaist.ac.kr; Lee, Chang-Min; Lim, Hee-Jin [Department of Physics, KAIST, Daejeon 305-701 (Korea, Republic of); Schlereth, Thomas W.; Kamp, Martin [Technische Physik, Physikalisches Institut and Wilhelm Conrad Röntgen-Center for Complex Material Systems, Universität Würzburg, Am Hubland, D-97074 Würzburg (Germany); Höfling, Sven [Technische Physik, Physikalisches Institut and Wilhelm Conrad Röntgen-Center for Complex Material Systems, Universität Würzburg, Am Hubland, D-97074 Würzburg (Germany); SUPA, School of Physics and Astronomy, University of St. Andrews, St. Andrews KY16 9SS (United Kingdom); Lee, Yong-Hee [Department of Physics, KAIST, Daejeon 305-701 (Korea, Republic of); Graduate School of Nanoscience and Technology (WCU), KAIST, Daejeon 305-701 (Korea, Republic of)

    2015-08-24

    A single photon source plays a key role in quantum applications such as quantum computers and quantum communications. Epitaxially grown quantum dots are one of the promising platforms to implement a good single photon source. However, it is challenging to realize an efficient single photon source based on semiconductor materials due to their high refractive index. Here we demonstrate a direct fiber coupled single photon source with high collection efficiency by employing a photonic crystal (PhC) waveguide and a tapered micro-fiber. To confirm the single photon nature, the second-order correlation function g{sup (2)}(τ) is measured with a Hanbury Brown-Twiss setup. The measured g{sup (2)}(0) value is 0.15, and we can estimate 24% direct collection efficiency from a quantum dot to the fiber.

  10. Coherent single-photon absorption by single emitters coupled to 1D nanophotonic waveguides

    DEFF Research Database (Denmark)

    Chen, Yuntian; Wubs, Martijn; Mørk, Jesper

    2012-01-01

    We have derived an efficient model that allows calculating the dynamical single-photon absorption of an emitter coupled to a waveguide. We suggest a novel and simple structure that leads to strong single-photon absorption.......We have derived an efficient model that allows calculating the dynamical single-photon absorption of an emitter coupled to a waveguide. We suggest a novel and simple structure that leads to strong single-photon absorption....

  11. Direct detection of a single photon by humans

    Science.gov (United States)

    Tinsley, Jonathan N.; Molodtsov, Maxim I.; Prevedel, Robert; Wartmann, David; Espigulé-Pons, Jofre; Lauwers, Mattias; Vaziri, Alipasha

    2016-01-01

    Despite investigations for over 70 years, the absolute limits of human vision have remained unclear. Rod cells respond to individual photons, yet whether a single-photon incident on the eye can be perceived by a human subject has remained a fundamental open question. Here we report that humans can detect a single-photon incident on the cornea with a probability significantly above chance. This was achieved by implementing a combination of a psychophysics procedure with a quantum light source that can generate single-photon states of light. We further discover that the probability of reporting a single photon is modulated by the presence of an earlier photon, suggesting a priming process that temporarily enhances the effective gain of the visual system on the timescale of seconds. PMID:27434854

  12. New Generation of Superconducting Nanowire Single-Photon Detectors

    Directory of Open Access Journals (Sweden)

    Goltsman G.N.

    2015-01-01

    Full Text Available We present an overview of recent results for new generation of infrared and optical superconducting nanowire single-photon detectors (SNSPDs that has already demonstrated a performance that makes them devices-of-choice for many applications. SNSPDs provide high efficiency for detecting individual photons while keeping dark counts and timing jitter minimal. Besides superior detection performance over a broad optical bandwidth, SNSPDs are also compatible with an integrated optical platform as a crucial requirement for applications in emerging quantum photonic technologies. By embedding SNSPDs in nanophotonic circuits we realize waveguide integrated single photon detectors which unite all desirable detector properties in a single device.

  13. High-Performance Single-Photon Sources via Spatial Multiplexing

    Science.gov (United States)

    2014-01-01

    ingredient for tasks such as quantum cryptography , quantum repeater, quantum teleportation, quantum computing, and truly-random number generation. Recently...SECURITY CLASSIFICATION OF: Single photons sources are desired for many potential quantum information applications. One common method to produce...photons sources are desired for many potential quantum information applications. One common method to produce single photons is based on a “heralding

  14. Temporal shaping of single photons enabled by entanglement

    Science.gov (United States)

    Averchenko, Valentin; Sych, Denis; Schunk, Gerhard; Vogl, Ulrich; Marquardt, Christoph; Leuchs, Gerd

    2017-10-01

    We present a method to produce pure single photons with an arbitrary designed temporal shape in a heralded way. As an indispensable resource, the method uses pairs of time-energy entangled photons. One photon of a pair undergoes temporal amplitude-phase modulation according to the desired shape. Subsequent frequency-resolved detection of the modulated photon heralds its entangled counterpart in a pure quantum state. The temporal shape of the heralded photon is indirectly affected by the modulation in the heralding arm. We derive conditions for which the shape of the heralded photon is given by the modulation function. The method can be implemented with various sources of time-energy entangled photons. In particular, using entangled photons from parametric down-conversion the method provides a simple means to generate pure shaped photons with an unprecedented broad range of temporal durations, from tenths of femtoseconds to microseconds. This shaping of single photons will push forward the implementation of scalable multidimensional quantum information protocols, efficient photon-matter coupling, and quantum control at the level of single quanta.

  15. Efficient Generation of Frequency-Multiplexed Entangled Single Photons

    Science.gov (United States)

    Qiu, Tian-Hui; Xie, Min

    2016-12-01

    We present two schemes to generate frequency-multiplexed entangled (FME) single photons by coherently mapping photonic entanglement into and out of a quantum memory based on Raman interactions. By splitting a single photon and performing subsequent state transfer, we separate the generation of entanglement and its frequency conversion, and find that the both progresses have the characteristic of inherent determinacy. Our theory can reproduce the prominent features of observed results including pulse shapes and the condition for deterministically generating the FME single photons. The schemes are suitable for the entangled photon pairs with a wider frequency range, and could be immune to the photon loss originating from cavity-mode damping, spontaneous emission, and the dephasing due to atomic thermal motion. The sources might have significant applications in wavelength-division-multiplexing quantum key distribution.

  16. Brain mapping with single photon emission CT.

    Science.gov (United States)

    Matthew, E; Hill, T C

    1998-02-01

    To investigate the feasibility of performing brain mapping studies by using cortical activation paradigms and single photon emission computed tomography (SPECT) and to evaluate methods of analysis. Twenty healthy volunteers underwent technetium-99m bicisate SPECT under baseline conditions and during either full-field or right hemifield visual stimulation with a black and white reversing checkerboard pattern. Changes in regional cerebral perfusion were measured by using regions of interest (ROIs) and statistical parametric mapping. ROI analysis identified statistically significant increases in perfusion in the occipital cortex with full-field visual stimulation (mean +/- standard error of the mean percentage change from baseline: left, 8.0 +/- 1.5; right, 6.6 +/- 2.4). With right hemifield visual stimulation, perfusion was significantly increased only in the left occipital cortex (left, 5.2 +/- 1.5; right, -0.2 +/- 1.9). Statistical parametric mapping showed areas of activation (more than 100 voxel clusters showed significant change from baseline at a threshold value of P or = 2.58) in the left primary visual cortex (right hemifield visual stimulation) and in both right and left primary visual areas (full-field visual stimulation). Brain mapping studies were preformed with Tc-99m bicisate SPECT, and activation-induced changes were visualized and measured. These methods can be applied to develop improved methods of diagnosis and assessment of treatment outcome in patients with neuropsychiatric disorders.

  17. A four-pixel single-photon pulse-position array fabricated from WSi superconducting nanowire single-photon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Verma, V. B., E-mail: verma@nist.gov; Horansky, R.; Lita, A. E.; Mirin, R. P.; Nam, S. W. [National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305 (United States); Marsili, F.; Stern, J. A.; Shaw, M. D. [Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, California 91109 (United States)

    2014-02-03

    We demonstrate a scalable readout scheme for an infrared single-photon pulse-position camera consisting of WSi superconducting nanowire single-photon detectors. For an N × N array, only 2 × N wires are required to obtain the position of a detection event. As a proof-of-principle, we show results from a 2 × 2 array.

  18. Electrically driven single-photon emission from an isolated single molecule.

    Science.gov (United States)

    Zhang, Li; Yu, Yun-Jie; Chen, Liu-Guo; Luo, Yang; Yang, Ben; Kong, Fan-Fang; Chen, Gong; Zhang, Yang; Zhang, Qiang; Luo, Yi; Yang, Jin-Long; Dong, Zhen-Chao; Hou, J G

    2017-09-18

    Electrically driven molecular light emitters are considered to be one of the promising candidates as single-photon sources. However, it is yet to be demonstrated that electrically driven single-photon emission can indeed be generated from an isolated single molecule notwithstanding fluorescence quenching and technical challenges. Here, we report such electrically driven single-photon emission from a well-defined single molecule located inside a precisely controlled nanocavity in a scanning tunneling microscope. The effective quenching suppression and nanocavity plasmonic enhancement allow us to achieve intense and stable single-molecule electroluminescence. Second-order photon correlation measurements reveal an evident photon antibunching dip with the single-photon purity down to g (2) (0) = 0.09, unambiguously confirming the single-photon emission nature of the single-molecule electroluminescence. Furthermore, we demonstrate an ultrahigh-density array of identical single-photon emitters.Molecular emitters offer a promising solution for single-photon generation. Here, by exploiting electronic decoupling by an ultrathin dielectric spacer and emission enhancement by a resonant plasmonic nanocavity, the authors demonstrate electrically driven single-photon emission from a single molecule.

  19. Quantum key distribution in single-photon communication system

    Science.gov (United States)

    Tretyakov, D. B.; Kolyako, A. V.; Pleshkov, A. S.; Entin, V. M.; Ryabtsev, I. I.; Neizvestny, I. G.

    2016-09-01

    This paper presents a brief review of experimental studies in quantum cryptography and quantum key distribution by single photons in atmospheric and fiber-optic quantum communication channels. Two experimental setups for quantum key distribution developed at the Rzhanov Institute of Semiconductor Physics SB RAS are described. The dependence of the quantum key distribution rate on the average number of photons μ in the laser pulse was studied. For μ > 0.3, there is a discrepancy between theory and experiment. The reasons for this are, first, the nonzero probability of multiphoton pulses occurring in quantum transmission and counted as single photons by single-photon detectors and, second, the rejection of the cases where several single-photon detectors click simultaneously in quantum key sifting because the measurement result is not determined in these cases.

  20. A novel high-efficiency single-mode quantum dot single photon source

    DEFF Research Database (Denmark)

    Gerard, J.M.; Gregersen, Niels; Nielsen, Torben Roland

    2008-01-01

    We present a novel single-mode single photon source exploiting the emission of a semiconductor quantum dot (QD) located inside a photonic wire. Besides an excellent coupling (>95%) of QD spontaneous emission to the fundamental guided mode [1], we show that a single photon collection efficiency...... above 80% within a 0.5 numerical aperture can be achieved using a bottom Bragg mirror and a tapering of the nanowire tip. Because this photon collection strategy does not exploit the Purcell effect, it could also be efficiently applied to broadband single photon emitters such as F-centers in diamond....

  1. Quantum private comparison employing single-photon interference

    Science.gov (United States)

    Liu, Bin; Xiao, Di; Huang, Wei; Jia, Heng-Yue; Song, Ting-Ting

    2017-07-01

    As a typical quantum cryptographic task between distrustful participants, quantum private comparison (QPC) has attracted a lot of attention in recent years. Here we propose two QPC protocols employing single-photon interference, a typical and interesting technology for quantum communications. Compared with the previous QPC protocols employing normal single states or entangled states, the proposed protocols achieve lower communication complexity utilizing the characteristics of single-photon interference. And we also proved the security of the proposed protocols in theory.

  2. Novel single photon sources for new generation of quantum communications

    Science.gov (United States)

    2017-06-13

    state single photon sources that was published in Nature Photonics in October 2016. 15. SUBJECT TERMS diamond color center, diamond, AOARD 16. SECURITY...06/2017 PI and Co-PI information: Igor Aharonovich, igor.aharonovich@uts.edu.au, University of Technology Sydney, School of Mathematical and...manipulation of a silicon vacancy color cent er in a nanodiamond. We demonstrate ultra fast coherent control of a photon, that make s this defect

  3. Frequency Conversion of Single Photons: Physics, Devices, and Applications

    Science.gov (United States)

    2012-07-01

    89 6.7 Rabi oscillations in photon counts for downconverted quantum dot single photons...dot, and show that the photon statistics of the quantum dot emission are preserved. Additionally, through the observation of Rabi oscillations in the...InAs is grown by molecular beam epitaxy (MBE, [119]) on a GaAs substrate, due to the lattice mismatch between InAs and GaAs, after the growth of a

  4. Quantum non-Gaussian Depth of Single-Photon States.

    Science.gov (United States)

    Straka, Ivo; Predojević, Ana; Huber, Tobias; Lachman, Lukáš; Butschek, Lorenz; Miková, Martina; Mičuda, Michal; Solomon, Glenn S; Weihs, Gregor; Ježek, Miroslav; Filip, Radim

    2014-11-28

    We introduce and experimentally explore the concept of the non-Gaussian depth of single-photon states with a positive Wigner function. The depth measures the robustness of a single-photon state against optical losses. The directly witnessed quantum non-Gaussianity withstands significant attenuation, exhibiting a depth of 18 dB, while the nonclassicality remains unchanged. Quantum non-Gaussian depth is an experimentally approachable quantity that is much more robust than the negativity of the Wigner function. Furthermore, we use it to reveal significant differences between otherwise strongly nonclassical single-photon sources.

  5. Nanofabrication of Plasmonic Circuits Containing Single Photon Sources

    DEFF Research Database (Denmark)

    Siampour, Hamidreza; Kumar, Shailesh; Bozhevolnyi, Sergey I.

    2017-01-01

    Nanofabrication of photonic components based on dielectric loaded surface plasmon polariton waveguides (DLSPPWs) excited by single nitrogen vacancy (NV) centers in nanodiamonds is demonstrated. DLSPPW circuits are built around NV containing nanodiamonds, which are certified to be single-photon...... emitters, using electron-beam lithography of hydrogen silsesquioxane (HSQ) resist on silver-coated silicon substrates. A propagation length of 20 ± 5 μm for the NV single-photon emission is measured with DLSPPWs. A 5-fold enhancement in the total decay rate, and 58% coupling efficiency to the DLSPPW mode...

  6. Scalable Quantum Photonics with Single Color Centers in Silicon Carbide.

    Science.gov (United States)

    Radulaski, Marina; Widmann, Matthias; Niethammer, Matthias; Zhang, Jingyuan Linda; Lee, Sang-Yun; Rendler, Torsten; Lagoudakis, Konstantinos G; Son, Nguyen Tien; Janzén, Erik; Ohshima, Takeshi; Wrachtrup, Jörg; Vučković, Jelena

    2017-03-08

    Silicon carbide is a promising platform for single photon sources, quantum bits (qubits), and nanoscale sensors based on individual color centers. Toward this goal, we develop a scalable array of nanopillars incorporating single silicon vacancy centers in 4H-SiC, readily available for efficient interfacing with free-space objective and lensed-fibers. A commercially obtained substrate is irradiated with 2 MeV electron beams to create vacancies. Subsequent lithographic process forms 800 nm tall nanopillars with 400-1400 nm diameters. We obtain high collection efficiency of up to 22 kcounts/s optical saturation rates from a single silicon vacancy center while preserving the single photon emission and the optically induced electron-spin polarization properties. Our study demonstrates silicon carbide as a readily available platform for scalable quantum photonics architecture relying on single photon sources and qubits.

  7. Scalable Quantum Photonics with Single Color Centers in Silicon Carbide

    Science.gov (United States)

    Radulaski, Marina; Widmann, Matthias; Niethammer, Matthias; Zhang, Jingyuan Linda; Lee, Sang-Yun; Rendler, Torsten; Lagoudakis, Konstantinos G.; Son, Nguyen Tien; Janzén, Erik; Ohshima, Takeshi; Wrachtrup, Jörg; Vučković, Jelena

    2017-03-01

    Silicon carbide is a promising platform for single photon sources, quantum bits (qubits) and nanoscale sensors based on individual color centers. Towards this goal, we develop a scalable array of nanopillars incorporating single silicon vacancy centers in 4H-SiC, readily available for efficient interfacing with free-space objective and lensed-fibers. A commercially obtained substrate is irradiated with 2 MeV electron beams to create vacancies. Subsequent lithographic process forms 800 nm tall nanopillars with 400-1,400 nm diameters. We obtain high collection efficiency, up to 22 kcounts/s optical saturation rates from a single silicon vacancy center, while preserving the single photon emission and the optically induced electron-spin polarization properties. Our study demonstrates silicon carbide as a readily available platform for scalable quantum photonics architecture relying on single photon sources and qubits.

  8. Simultaneous, Full Characterization of a Single-Photon State

    Directory of Open Access Journals (Sweden)

    Tim Thomay

    2017-11-01

    Full Text Available As single-photon sources become more mature and are used more often in quantum information, communications, and measurement applications, their characterization becomes more important. Single-photon-like light is often characterized by its brightness, as well as two quantum properties: the suppression of multiphoton content and the photon indistinguishability. While it is desirable to obtain these quantities from a single measurement, currently two or more measurements are required. Here, we show that using two-photon (n=2 number-resolving detectors, one can completely characterize single-photon-like states in a single measurement, where previously two or more measurements were necessary. We simultaneously determine the brightness, the suppression of multiphoton states, the indistinguishability, and the statistical distribution of Fock states to third order for a quantum light source. We find n≥3 number-resolving detectors provide no additional advantage in the single-photon characterization. The new method extracts more information per experimental trial than a conventional measurement for all input states and is particularly more efficient for statistical mixtures of photon states. Thus, using this n=2, number-resolving detector scheme will provide advantages in a variety of quantum optics measurements and systems.

  9. Enhancement of Single-Photon Sources with Metamaterials

    Science.gov (United States)

    Shalaginov, M. Y.; Bogdanov, S.; Vorobyov, V. V.; Lagutchev, A. S.; Kildishev, A. V.; Akimov, A. V.; Boltasseva, A.; Shalaev, V. M.

    2015-06-01

    Scientists are looking for new, breakthrough solutions that can greatly advance computing and networking systems. These solutions will involve quantum properties of matter and light as promised by the ongoing experimental and theoretical work in the areas of quantum computation and communication. Quantum photonics is destined to play a central role in the development of such technologies due to the high transmission capacity and outstanding low-noise properties of photonic information channels. Among the vital problems to be solved in this direction, are efficient generation and collection of single photons. One approach to tackle these problems is based on engineering emission properties of available single-photon sources using metamaterials. Metamaterials are artificially engineered structures with sub-wavelength features whose optical properties go beyond the limitations of conventional materials. As promising single-photon sources, we have chosen nitrogen-vacancy (NV) color centers in diamond, which are capable to operate stably in a single-photon regime at room temperature in a solid state environment. In this chapter, we report both theoretical and experimental studies of the radiation from a nanodiamond single NV center placed near a hyperbolic metamaterial (HMM). In particular, we derive the reduction of excited-state lifetime and the enhancement of collected single-photon emission rate and compare them with the experimental observations. These results could be of great impact for future integrated quantum sources, especially owing to a CMOS-compatible approach to HMM synthesis.

  10. Extent of sensitivity of single photon production to parton distribution ...

    Indian Academy of Sciences (India)

    The prompt photon cross-section is found to be described equally well by all the PDFs within the experimental errors at the RHIC and the LHC energies. The deviation in the single-prompt photon yield for different PDF sets is within ±20% when compared to CTEQ4M, indicating the upper bound of uncertainty in determining ...

  11. Total teleportation of a single-photon state

    Energy Technology Data Exchange (ETDEWEB)

    Humble, Travis S [ORNL; Bennink, Ryan S [ORNL; Grice, Warren P [ORNL

    2008-01-01

    Recent demonstrations of teleportation have transferred quantum information encoded into either polarization or field-quadrature degrees of freedom (DOFs), but an outstanding question is how to simultaneously teleport quantum information encoded into multiple DOFs. We describe how the transverse-spatial, spectral and polarization states of a single photon can be simultaneously teleported using a pair of multimode, polarization-entangled photons derived from spontaneous parametric down-conversion. Furthermore, when the initial photon pair is maximally entangled in the spatial, spectral, and polarization DOFs then the photon s full quantum state can be reliably teleported using a Bell-state measurement based on sum-frequency generation.

  12. Near-unity efficiency, single-photon sources based on tapered photonic nanowires

    DEFF Research Database (Denmark)

    Bleuse, Joël; Munsch, Mathieu; Claudon, Julien

    2012-01-01

    Single-photon emission from excitons in InAs Quantum Dots (QD) embedded in GaAs Tapered Photonic Wires (TPW) already demonstrated a 0.72 collection efficiency, with TPWs were the apex is the sharp end of the cone. Going to alternate designs, still based on the idea of the adiabatic deconfinement...

  13. Controlling light emission from single-photon sources using photonic nanowires

    DEFF Research Database (Denmark)

    Gregersen, Niels; Chen, Yuntian; Mørk, Jesper

    2012-01-01

    are used to tailor the far-field emission pattern. This non-resonant approach relaxes the demands to fabrication perfection, allowing for record-high measured efficiency of fabricated nanowire single-photon sources. We review recent progress in photonic nanowire technology and present next generation...

  14. Multiple-Event, Single-Photon Counting Imaging Sensor

    Science.gov (United States)

    Zheng, Xinyu; Cunningham, Thomas J.; Sun, Chao; Wang, Kang L.

    2011-01-01

    The single-photon counting imaging sensor is typically an array of silicon Geiger-mode avalanche photodiodes that are monolithically integrated with CMOS (complementary metal oxide semiconductor) readout, signal processing, and addressing circuits located in each pixel and the peripheral area of the chip. The major problem is its single-event method for photon count number registration. A single-event single-photon counting imaging array only allows registration of up to one photon count in each of its pixels during a frame time, i.e., the interval between two successive pixel reset operations. Since the frame time can t be too short, this will lead to very low dynamic range and make the sensor merely useful for very low flux environments. The second problem of the prior technique is a limited fill factor resulting from consumption of chip area by the monolithically integrated CMOS readout in pixels. The resulting low photon collection efficiency will substantially ruin any benefit gained from the very sensitive single-photon counting detection. The single-photon counting imaging sensor developed in this work has a novel multiple-event architecture, which allows each of its pixels to register as more than one million (or more) photon-counting events during a frame time. Because of a consequently boosted dynamic range, the imaging array of the invention is capable of performing single-photon counting under ultra-low light through high-flux environments. On the other hand, since the multiple-event architecture is implemented in a hybrid structure, back-illumination and close-to-unity fill factor can be realized, and maximized quantum efficiency can also be achieved in the detector array.

  15. Category theoretic analysis of single-photon decision maker

    CERN Document Server

    Kim, Makoto Naruse Song-Ju; Berthel, Martin; Drezet, Aurélien; Huant, Serge; Hori, Hirokazu

    2016-01-01

    Decision making is a vital function in the era of artificial intelligence; however, its physical realizations and their theoretical fundamentals are not yet known. In our former study [Sci. Rep. 5, 513253 (2015)], we demonstrated that single photons can be used to make decisions in uncertain, dynamically changing environments. The multi-armed bandit problem was successfully solved using the dual probabilistic and particle attributes of single photons. Herein, we present the category theoretic foundation of the single-photon-based decision making, including quantitative analysis that agrees well with the experimental results. The category theoretic model unveils complex interdependencies of the entities of the subject matter in the most simplified manner, including a dynamically changing environment. In particular, the octahedral structure in triangulated categories provides a clear understanding of the underlying mechanisms of the single-photon decision maker. This is the first demonstration of a category the...

  16. Interaction of independent single photons based on integrated nonlinear optics.

    Science.gov (United States)

    Guerreiro, T; Pomarico, E; Sanguinetti, B; Sangouard, N; Pelc, J S; Langrock, C; Fejer, M M; Zbinden, H; Thew, R T; Gisin, N

    2013-01-01

    The parametric interaction of light beams in nonlinear materials is usually thought to be too weak to be observed when the fields involved are at the single-photon level. However, such single-photon level nonlinearity is not only fundamentally fascinating but holds great potential for emerging technologies and applications involving heralding entanglement at a distance. Here we use a high-efficiency waveguide to demonstrate the sum-frequency generation between a single photon and a single-photon level coherent state. The use of an integrated, solid state, room temperature device and telecom wavelengths makes this type of system directly applicable to future quantum communication technologies such as device-independent quantum key distribution.

  17. Single Photon Avalanche Diodes: Towards the Large Bidimensional Arrays

    Directory of Open Access Journals (Sweden)

    Emilio Sciacca

    2008-08-01

    Full Text Available Single photon detection is one of the most challenging goals of photonics. In recent years, the study of ultra-fast and/or low-intensity phenomena has received renewed attention from the academic and industrial communities. Intense research activity has been focused on bio-imaging applications, bio-luminescence, bio-scattering methods, and, more in general, on several applications requiring high speed operation and high timing resolution. In this paper we present design and characterization of bi-dimensional arrays of a next generation of single photon avalanche diodes (SPADs. Single photon sensitivity, dark noise, afterpulsing and timing resolution of the single SPAD have been examined in several experimental conditions. Moreover, the effects arising from their integration and the readout mode have also been deeply investigated.

  18. Secure communication with a heralded single-photon source

    Energy Technology Data Exchange (ETDEWEB)

    Trifonov, A; Zavriyev, A [MagiQ Technologies, Inc., 11 Ward Street 300, Somerville, MA 02143 (United States)

    2005-12-01

    Secure long distance communication over optical fibres requires robust data encryption. While the encryption itself can be conducted using classical algorithms, there is no unconditionally secure method of classical key distribution. Quantum key distribution (QKD), on the other hand, can provide users of the optical networks with unconditionally secure keys. Since QKD is based on single-photon transmission, one of the challenging tasks is to overcome the distance limitation imposed by the losses in optical fibres. In this work we show that single-photon based QKD outperforms the industry-standard weak coherent pulse approach. We also present our recent experimental results on building a heralded single-photon source based on spontaneous parametric down-conversion of CW light and discuss problems and challenges of heralded single-photon generation in the CW regime.

  19. Snapping single flying photons based on tunneling assisted multiphoton absorption

    Science.gov (United States)

    Li, Zhengyong; Matthiesen, Clemens; Wu, Chongqing; Atature, Mete; Institute of Optical Information Team; Quantum Information and Nanoscale Metrology Group Team

    2014-03-01

    Multi-photon absorption (MPA) can be used to measure the temporal correlation of flying photons at a much shorter timescale within a maximum delay (about 1 fs) given by the Heisenberg principle. We first measure the 2PA and 3PA of GaAsP material by using a mode locked laser (Mira 900) with pulse width less than 100 fs (76 MHz), and obtain pronounced 2PA and 3PA at 60 mW and 130 mW respectively (wavelength: 900 nm). We further strengthen the absorption process by using an extra electrical field through photon assisted tunneling, and double the MPA coefficient by a bias voltage of 5 V. Then, we demonstrate the tunneling assisted MPA in GaAsP by a pump-probe scheme, and successfully snap flying single photons in 1550-nm telecom band by using a synchronous 900-nm fs sampling pulse train, which scanning the flying photons through a motorizing translation stage. Experimental results show that the time-domain width of the single photon is around 250 fs, and further statistical investigations demonstrate that the single photons follow subPoisson distribution with Mandel Q parameter of about -0.2, which means the photons are antibunching definitely. The authors acknowledge the support of the NSFC (Nos.11274037 and 61275075), the NCET (No NCET-12-0765), and the FANEDD (No 201236).

  20. Photonics

    CERN Document Server

    Andrews, David L

    2015-01-01

    Discusses the basic physical principles underlying Biomedical Photonics, spectroscopy and microscopy This volume discusses biomedical photonics, spectroscopy and microscopy, the basic physical principles underlying the technology and its applications. The topics discussed in this volume are: Biophotonics; Fluorescence and Phosphorescence; Medical Photonics; Microscopy; Nonlinear Optics; Ophthalmic Technology; Optical Tomography; Optofluidics; Photodynamic Therapy; Image Processing; Imaging Systems; Sensors; Single Molecule Detection; Futurology in Photonics. Comprehensive and accessible cov

  1. Graphene-Based Josephson-Junction Single-Photon Detector

    Science.gov (United States)

    Walsh, Evan D.; Efetov, Dmitri K.; Lee, Gil-Ho; Heuck, Mikkel; Crossno, Jesse; Ohki, Thomas A.; Kim, Philip; Englund, Dirk; Fong, Kin Chung

    2017-08-01

    We propose to use graphene-based Josephson junctions (GJJs) to detect single photons in a wide electromagnetic spectrum from visible to radio frequencies. Our approach takes advantage of the exceptionally low electronic heat capacity of monolayer graphene and its constricted thermal conductance to its phonon degrees of freedom. Such a system could provide high-sensitivity photon detection required for research areas including quantum information processing and radio astronomy. As an example, we present our device concepts for GJJ single-photon detectors in both the microwave and infrared regimes. The dark count rate and intrinsic quantum efficiency are computed based on parameters from a measured GJJ, demonstrating feasibility within existing technologies.

  2. Interferometric measurement of the helical mode of a single photon

    Energy Technology Data Exchange (ETDEWEB)

    Galvez, E J; Coyle, L E; Johnson, E; Reschovsky, B J, E-mail: egalvez@colgate.edu [Department of Physics and Astronomy, Colgate University, 13 Oak Drive, Hamilton, NY 13346 (United States)

    2011-05-15

    We present measurements of the helical mode of single photons and do so by sending heralded photons through a Mach-Zehnder interferometer that prepares the light in a helical mode with topological charge one, and interferes it with itself in the fundamental non-helical mode. Masks placed after the interferometer were used to diagnose the amplitude and phase of the mode of the light. Auxiliary measurements verified that the light was in a non-classical state. The results are in good agreement with theory. The experiments demonstrate in a direct way that single photons carry the entire spatial helical-mode information.

  3. Highly efficient photonic nanowire single-photon sources for quantum information applications

    DEFF Research Database (Denmark)

    Gregersen, Niels; Claudon, J.; Munsch, M.

    2013-01-01

    Within the emerging field of optical quantum information processing, the current challenge is to construct the basic building blocks for the quantum computing and communication systems. A key component is the singlephoton source (SPS) capable of emitting single photons on demand. Ideally, the SPS...... must feature near-unity efficiency, where the efficiency is defined as the number of detected photons per trigger, the probability g(2)(τ=0) of multi-photon emission events should be 0 and the emitted photons are required to be indistinguishable. An optically or electrically triggered quantum light...... emitter, e.g. a nitrogen-vacancy center or a semiconductor quantum dot (QD), embedded in a solid-state semiconductor host material appears as an attractive platform for generating such single photons. However, for a QD in bulk material, the large index contrast at the semiconductor-air interface leads...

  4. Recyclable amplification for single-photon entanglement from photon loss and decoherence

    Science.gov (United States)

    Zhou, Lan; Chen, Ling-Quan; Zhong, Wei; Sheng, Yu-Bo

    2018-01-01

    We put forward a highly efficient recyclable single-photon assisted amplification protocol, which can protect single-photon entanglement (SPE) from photon loss and decoherence. Making use of quantum nondemolition detection gates constructed with the help of cross-Kerr nonlinearity, our protocol has some attractive advantages. First, the parties can recover less-entangled SPE to be maximally entangled SPE, and reduce photon loss simultaneously. Second, if the protocol fails, the parties can repeat the protocol to reuse some discarded items, which can increase the success probability. Third, when the protocol is successful, they can similarly repeat the protocol to further increase the fidelity of the SPE. Thereby, our protocol provides a possible way to obtain high entanglement, high fidelity and high success probability simultaneously. In particular, our protocol shows higher success probability in the practical high photon loss channel. Based on the above features, our amplification protocol has potential for future application in long-distance quantum communication.

  5. Fast time-domain measurements on telecom single photons

    Science.gov (United States)

    Allgaier, Markus; Vigh, Gesche; Ansari, Vahid; Eigner, Christof; Quiring, Viktor; Ricken, Raimund; Brecht, Benjamin; Silberhorn, Christine

    2017-09-01

    Direct measurements on the temporal envelope of quantum light are a challenging task and not many examples are known because most classical pulse characterisation methods do not work on the single-photon level. Knowledge of both spectrum and timing can, however, give insights on properties that cannot be determined by the spectral intensity alone. While temporal measurements on single photons on timescales of tens of picoseconds are possible with superconducting photon detectors, and picosecond measurements have been performed using streak cameras, there are no commercial single-photon sensitive devices with femtosecond resolution available. While time-domain sampling using sum-frequency generation has already been exploited for such a measurement, inefficient conversion has necessitated long integration times to build the temporal profile. We demonstrate a highly efficient waveguided sum-frequency generation process in Lithium Niobate to measure the temporal envelope of single photons with femtosecond resolution with short enough acquisition time to provide a live-view of the measurement. We demonstrate the measurement technique and combine it with spectral measurements using a dispersive-fibre time-of-flight spectrometer to determine upper and lower bounds for the spectral purity of heralded single photons. The approach complements the joint spectral intensity measurements as a measure on the purity can be given without knowledge of the spectral phase.

  6. Deterministic Integration of Single Photon Sources in Silicon Based Photonic Circuits.

    Science.gov (United States)

    Zadeh, Iman Esmaeil; Elshaari, Ali W; Jöns, Klaus D; Fognini, Andreas; Dalacu, Dan; Poole, Philip J; Reimer, Michael E; Zwiller, Val

    2016-04-13

    A major step toward fully integrated quantum optics is the deterministic incorporation of high quality single photon sources in on-chip optical circuits. We show a novel hybrid approach in which preselected III-V single quantum dots in nanowires are transferred and integrated in silicon based photonic circuits. The quantum emitters maintain their high optical quality after integration as verified by measuring a low multiphoton probability of 0.07 ± 0.07 and emission line width as narrow as 3.45 ± 0.48 GHz. Our approach allows for optimum alignment of the quantum dot light emission to the fundamental waveguide mode resulting in very high coupling efficiencies. We estimate a coupling efficiency of 24.3 ± 1.7% from the studied single-photon source to the photonic channel and further show by finite-difference time-domain simulations that for an optimized choice of material and design the efficiency can exceed 90%.

  7. Single photon emission computed tomography for the diagnosis of coronary artery disease: an evidence-based analysis.

    Science.gov (United States)

    2010-01-01

    THE DIAGNOSIS OF CORONARY ARTERY DISEASE: An Evidence-Based AnalysisPease note that two related evidence-based analyses of non-invasive cardiac imaging technologies for the assessment of myocardial viability are also available on the MAS website:POSITRON EMISSION TOMOGRAPHY FOR THE ASSESSMENT OF MYOCARDIAL VIABILITY: An Evidence-Based AnalysisMAGNETIC RESONANCE IMAGING FOR THE ASSESSMENT OF MYOCARDIAL VIABILITY: an Evidence-Based AnalysisThe Toronto Health Economics and Technology Assessment Collaborative has also produced an associated economic report entitled:The Relative Cost-effectiveness of Five Non-invasive Cardiac Imaging Technologies for Diagnosing Coronary Artery Disease in Ontario [Internet]. Available from: http://theta.utoronto.ca/reports/?id=7 The objective of the analysis is to determine the diagnostic accuracy of single photon emission tomography (SPECT) in the diagnosis of coronary artery disease (CAD) compared to the reference standard of coronary angiography (CA). The analysis is primarily meant to allow for indirect comparisons between non-invasive strategies for the diagnosis of CAD, using CA as a reference standard. SPECT: Cardiac SPECT, or myocardial perfusion scintigraphy (MPS), is a widely used nuclear, non-invasive image acquisition technique for investigating ischemic heart disease. SPECT is currently appropriate for all aspects of detecting and managing ischemic heart disease including diagnosis, risk assessment/stratification, assessment of myocardial viability, and the evaluation of left ventricular function. Myocardial perfusion scintigraphy was originally developed as a two-dimensional planar imaging technique, but SPECT acquisition has since become the clinical standard in current practice. Cardiac SPECT for the diagnosis of CAD uses an intravenously administered radiopharmaceutical tracer to evaluate regional coronary blood flow usually at rest and after stress. The radioactive tracers thallium (201Tl) or technetium-99m (99mTc), or

  8. A search for single photon events in neutrino interactions

    Science.gov (United States)

    Kullenberg, C. T.; Mishra, S. R.; Dimmery, D.; Tian, X. C.; Autiero, D.; Gninenko, S.; Rubbia, A.; Alekhin, S.; Astier, P.; Baldisseri, A.; Baldo-Ceolin, M.; Banner, M.; Bassompierre, G.; Benslama, K.; Besson, N.; Bird, I.; Blumenfeld, B.; Bobisut, F.; Bouchez, J.; Boyd, S.; Bueno, A.; Bunyatov, S.; Camilleri, L.; Cardini, A.; Cattaneo, P. W.; Cavasinni, V.; Cervera-Villanueva, A.; Challis, R.; Chukanov, A.; Collazuol, G.; Conforto, G.; Conta, C.; Contalbrigo, M.; Cousins, R.; Degaudenzi, H.; De Santo, A.; Del Prete, T.; Di Lella, L.; do Couto e Silva, E.; Dumarchez, J.; Ellis, M.; Feldman, G. J.; Ferrari, R.; Ferrère, D.; Flaminio, V.; Fraternali, M.; Gaillard, J.-M.; Gangler, E.; Geiser, A.; Geppert, D.; Gibin, D.; Godley, A.; Gomez-Cadenas, J.-J.; Gosset, J.; Gößling, C.; Gouanère, M.; Grant, A.; Graziani, G.; Guglielmi, A.; Hagner, C.; Hernando, J.; Hurst, P.; Hyett, N.; Iacopini, E.; Joseph, C.; Juget, F.; Kent, N.; Klimov, O.; Kokkonen, J.; Kovzelev, A.; Krasnoperov, A.; Kim, J. J.; Kirsanov, M.; Kulagin, S.; Lacaprara, S.; Lachaud, C.; Lakić, B.; Lanza, A.; La Rotonda, L.; Laveder, M.; Letessier-Selvon, A.; Levy, J.-M.; Ling, J.; Linssen, L.; Ljubičić, A.; Long, J.; Lupi, A.; Lyubushkin, V.; Marchionni, A.; Martelli, F.; Méchain, X.; Mendiburu, J.-P.; Meyer, J.-P.; Mezzetto, M.; Moorhead, G. F.; Naumov, D.; Nédélec, P.; Nefedov, Yu.; Nguyen-Mau, C.; Orestano, D.; Pastore, F.; Peak, L. S.; Pennacchio, E.; Pessard, H.; Petti, R.; Placci, A.; Polesello, G.; Pollmann, D.; Polyarush, A.; Poulsen, C.; Popov, B.; Rebuffi, L.; Rico, J.; Riemann, P.; Roda, C.; Salvatore, F.; Samoylov, O.; Schahmaneche, K.; Schmidt, B.; Schmidt, T.; Sconza, A.; Scott, A. M.; Seaton, M. B.; Sevior, M.; Sillou, D.; Soler, F. J. P.; Sozzi, G.; Steele, D.; Stiegler, U.; Stipčević, M.; Stolarczyk, Th.; Tareb-Reyes, M.; Taylor, G. N.; Tereshchenko, V.; Toropin, A.; Touchard, A.-M.; Tovey, S. N.; Tran, M.-T.; Tsesmelis, E.; Ulrichs, J.; Vacavant, L.; Valdata-Nappi, M.; Valuev, V.; Vannucci, F.; Varvell, K. E.; Veltri, M.; Vercesi, V.; Vidal-Sitjes, G.; Vieira, J.-M.; Vinogradova, T.; Weber, F. V.; Weisse, T.; Wilson, F. F.; Winton, L. J.; Wu, Q.; Yabsley, B. D.; Zaccone, H.; Zuber, K.; Zuccon, P.

    2012-01-01

    We present a search for neutrino induced events containing a single, exclusive photon using data from the NOMAD experiment at the CERN SPS where the average energy of the neutrino flux is ≃ 25 GeV. The search is motivated by an excess of electron-like events in the 200-475 MeV energy region as reported by the MiniBooNE experiment. In NOMAD, photons are identified via their conversion to e+e- in an active target embedded in a magnetic field. The background to the single photon signal is dominated by the asymmetric decay of neutral pions produced either in a coherent neutrino-nucleus interaction, or in a neutrino-nucleon neutral current deep inelastic scattering, or in an interaction occurring outside the fiducial volume. All three backgrounds are determined in situ using control data samples prior to opening the 'signal-box'. In the signal region, we observe 155 events with a predicted background of 129.2 ± 8.5 ± 3.3. We interpret this as null evidence for excess of single photon events, and set a limit. Assuming that the hypothetical single photon has a momentum distribution similar to that of a photon from the coherent π0 decay, the measurement yields an upper limit on single photon events, < 4.0 ×10-4 per νμ charged current event. Narrowing the search to events where the photon is approximately collinear with the incident neutrino, we observe 78 events with a predicted background of 76.6 ± 4.9 ± 1.9 yielding a more stringent upper limit, < 1.6 ×10-4 per νμ charged current event.

  9. Microfiber coupled superconducting nanowire single-photon detectors

    Science.gov (United States)

    Xu, Yingxin; Wu, Junjie; Fang, Wei; You, Lixing; Tong, Limin

    2017-12-01

    Superconducting nanowires single-photon detectors (SNSPDs or SSPDs) have emerged as an attractive single-photon detection technology with high performance. Two types of SNSPDs have been developed so far. One is the standard-fiber-coupled SNSPD with the light normally incident on the meandered nanowires, the other is waveguide-coupled SNSPD with the nanowires fabricated on the surface of the waveguide which guides photons while the fiber is coupled to the waveguide. Here we propose a new type of SNSPD integrated with microfiber. The photons are guided by a microfiber and evanescently absorbed by the nanowire of SNSPD when the nanowire is parallel and very close to the microfiber. The numerical simulation results show that the fiber to detector coupling efficiency can be close to unity with optimized device structure/parameters. With a minimal total NbN nanowire length of about 300 μm, the absorption of the nanowire can reach 90%.

  10. Single mode dye-doped polymer photonic crystal lasers

    DEFF Research Database (Denmark)

    Christiansen, Mads Brøkner; Buss, Thomas; Smith, Cameron

    2010-01-01

    Dye-doped polymer photonic crystal (PhC) lasers fabricated by combined nanoimprint and photolithography are studied for their reproducibility and stability characteristics. We introduce a phase shift in the PhC lattice that substantially improves the yield of single wavelength emission. Single mode...

  11. Deterministic teleportation using single-photon entanglement as a resource

    DEFF Research Database (Denmark)

    Björk, Gunnar; Laghaout, Amine; Andersen, Ulrik L.

    2012-01-01

    We outline a proof that teleportation with a single particle is, in principle, just as reliable as with two particles. We thereby hope to dispel the skepticism surrounding single-photon entanglement as a valid resource in quantum information. A deterministic Bell-state analyzer is proposed which...

  12. Investigating and Improving Student Understanding of Quantum Mechanics in the Context of Single Photon Interference

    Science.gov (United States)

    Marshman, Emily; Singh, Chandralekha

    2017-01-01

    Single photon experiments involving a Mach-Zehnder interferometer can illustrate the fundamental principles of quantum mechanics, e.g., the wave-particle duality of a single photon, single photon interference, and the probabilistic nature of quantum measurement involving single photons. These experiments explicitly make the connection between the…

  13. Nanoantenna enhancement for telecom-wavelength superconducting single photon detectors.

    Science.gov (United States)

    Heath, Robert M; Tanner, Michael G; Drysdale, Timothy D; Miki, Shigehito; Giannini, Vincenzo; Maier, Stefan A; Hadfield, Robert H

    2015-02-11

    Superconducting nanowire single photon detectors are rapidly emerging as a key infrared photon-counting technology. Two front-side-coupled silver dipole nanoantennas, simulated to have resonances at 1480 and 1525 nm, were fabricated in a two-step process. An enhancement of 50 to 130% in the system detection efficiency was observed when illuminating the antennas. This offers a pathway to increasing absorption into superconducting nanowires, creating larger active areas, and achieving more efficient detection at longer wavelengths.

  14. Single-photon nonlinear optics with graphene plasmons.

    Science.gov (United States)

    Gullans, M; Chang, D E; Koppens, F H L; García de Abajo, F J; Lukin, M D

    2013-12-13

    We show that it is possible to realize significant nonlinear optical interactions at the few photon level in graphene nanostructures. Our approach takes advantage of the electric field enhancement associated with the strong confinement of graphene plasmons and the large intrinsic nonlinearity of graphene. Such a system could provide a powerful platform for quantum nonlinear optical control of light. As an example, we consider an integrated optical device that exploits this large nonlinearity to realize a single photon switch.

  15. Coherent single-photon absorption by single emitters coupled to one-dimensional nanophotonic waveguides

    DEFF Research Database (Denmark)

    Chen, Yuntian; Wubs, Martijn; Mørk, Jesper

    2011-01-01

    solutions for the dynamics of absorption, with maximum atomic excitation . We furthermore propose a terminated waveguide to aid the single-photon absorption. We found that for an emitter placed at an optimal distance from the termination, the maximum atomic excitation due to an incident single......We study the dynamics of single-photon absorption by a single emitter coupled to a one-dimensional waveguide that simultaneously provides channels for spontaneous emission (SE) decay and a channel for the input photon. We have developed a time-dependent theory that allows us to specify any input......-photon wavepacket can exceed 70%. This high value is a direct consequence of the high SE β-factor for emission into the waveguide. Finally, we have also explored whether waveguide dispersion could aid single-photon absorption by pulse shaping. For a Gaussian input wavepacket, we found that the absorption efficiency...

  16. Thallium-201 uptake in a benign thymoma

    Energy Technology Data Exchange (ETDEWEB)

    Campeau, R.J.; Ey, E.H.; Varma, D.G.

    1986-07-01

    A 68-year-old woman was admitted with atypical angina. A chest radiograph showed an anterior mediastinal mass that was confirmed on CT. The mass was relatively avascular and separate from the heart and great vessels. She underwent stress thallium testing that demonstrated no exercise-induced ischemia; however, an abnormal focus of thallium activity was present in the anterior mediastinum on stress and redistribution images. Cardiac catheterization demonstrated a normal left ventriculogram, coronary arteries and thoracic aorta. Subsequent surgery and pathologic examination revealed the mass to be a benign thymoma arising in the right lobe of the thymus gland.

  17. Cooperative single-photon subradiant states

    Science.gov (United States)

    Jen, H. H.; Chang, M.-S.; Chen, Y.-C.

    2016-07-01

    We propose a set of subradiant states which can be prepared and detected in a one-dimensional optical lattice. We find that the decay rates are highly dependent on the spatial phases imprinted on the atomic chain, which allows systematic investigations of the subradiance in fluorescence experiments. The time evolution of these states can have a long decay time where up to 100 ms of lifetime is predicted for 100 atoms. They can also show decayed Rabi-like oscillations with a beating frequency determined by the difference of the cooperative Lamb shift in the subspace. Experimental requirements are also discussed for practical implementation of the subradiant states. Our proposal provides a scheme for quantum storage of photons in arrays of two-level atoms through the preparation and detection of subradiant states, which offers opportunities for quantum many-body state preparation and quantum information processing in optical lattices.

  18. Photoconductance quantization in a single-photon detector

    Science.gov (United States)

    Kosaka, Hideo; Rao, Deepak S.; Robinson, Hans D.; Bandaru, Prabhakar; Sakamoto, Toshitsugu; Yablonovitch, Eli

    2002-05-01

    We have made a single-photon detector that relies on photoconductive gain in a narrow electron channel in an AlyGa1-yAs/GaAs two-dimensional electron gas. Given that the electron channel is one dimensional, the photoinduced conductance has plateaus at multiples of the quantum conductance 2e2/h. Superimposed on these broad conductance plateaus are many sharp, small, conductance steps associated with single-photon absorption events that produce individual photocarriers. This is a first step toward a photoconductive detector that could measure a single photon, while safely storing and protecting the spin degree of freedom of its photocarrier, but we have not actually achieved that goal.

  19. The photonic nanowire: an emerging platform for highly efficient single-photon sources for quantum information applications

    DEFF Research Database (Denmark)

    Gregersen, Niels; Munsch, Mathieu; Malik, Nitin S.

    2013-01-01

    Efficient coupling between a localized quantum emitter and a well defined optical channel represents a powerful route to realize single-photon sources and spin-photon interfaces. The tailored fiber-like photonic nanowire embedding a single quantum dot has recently demonstrated an appealing...

  20. Evaluation of the ID220 single photon avalanche diode for extended spectral range of photon time-of-flight spectroscopy

    DEFF Research Database (Denmark)

    Nielsen, Otto Højager Attermann; Dahl, Anders Bjorholm; Anderson-Engels, Stefan

    This paper describe the performance of the ID220 single photon avalanche diode for single photon counting, and investigates its performance for photon time-of-flight (PToF) spectroscopy. At first this report will serve as a summary to the group for PToF spectroscopy at the Department of Physics...

  1. Lecture demonstrations of interference and quantum erasing with single photons

    Science.gov (United States)

    Dimitrova, T. L.; Weis, A.

    2009-07-01

    Single-photon interference is a beautiful manifestation of the wave-particle duality of light and the double-slit Gedankenexperiment is a standard lecture example for introducing quantum mechanical reality. Interference arises only if each photon can follow several (classical) paths from the source to the detector, and if one does not have the possibility to determine which specific path the photon has taken. Attaching a specific label to the photon traveling along a specific path destroys the interference. However, in some cases those labels can be erased from the photon between leaving the apparatus and being detected, by which interference can be restored, a phenomenon called quantum erasing. We present lecture demonstration experiments that illustrate the wave-particle duality of light and the phenomenon of quantum erasing. Both experiments are first shown with strong light and, in a second step, on a photon-by-photon basis. The smooth transition from the quantum to the classical case can be shown in real time by varying the incident light intensity.

  2. A Variable Single Photon Plasmonic Beamsplitter

    DEFF Research Database (Denmark)

    Israelsen, Niels Møller; Kumar, Shailesh; Huck, Alexander

    Plasmonic structures can both be exploited for scaling down optical components beyond the diffraction limit and enhancing andcollecting the emission from a single dipole emitter. Here, we experimentally demonstrate adiabatic coupling between two silvernanowires using a nitrogen vacancy center as ...

  3. Interfering Heralded Single Photons from Two Separate Silicon Nanowires Pumped at Different Wavelengths

    Directory of Open Access Journals (Sweden)

    Xiang Zhang

    2016-08-01

    Full Text Available Practical quantum photonic applications require on-demand single photon sources. As one possible solution, active temporal and wavelength multiplexing has been proposed to build an on-demand single photon source. In this scheme, heralded single photons are generated from different pump wavelengths in many temporal modes. However, the indistinguishability of these heralded single photons has not yet been experimentally confirmed. In this work, we achieve 88% ± 8% Hong–Ou–Mandel quantum interference visibility from heralded single photons generated from two separate silicon nanowires pumped at different wavelengths. This demonstrates that active temporal and wavelength multiplexing could generate indistinguishable heralded single photons.

  4. Investigation of Hamamatsu H8500 phototubes as single photon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Montgomery, R.A. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi, 40, 00044 Frascati (Italy); Hoek, M. [Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, Johann-Joachim-Becher-Weg 45, D 55128 Mainz (Germany); Lucherini, V.; Mirazita, M.; Orlandi, A.; Anefalos Pereira, S.; Pisano, S. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi, 40, 00044 Frascati (Italy); Rossi, P. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi, 40, 00044 Frascati (Italy); Jefferson Laboratory, Thomas Jefferson National Accelerator Facility, 12000 Jefferson Avenue, Newport News, VA 23606 (United States); Viticchiè, A. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi, 40, 00044 Frascati (Italy); Witchger, A. [Department of Physics, Duquesne University, 317 Fisher Hall, Pittsburgh, PA 15282 (United States)

    2015-08-01

    We have investigated the response of a significant sample of Hamamatsu H8500 MultiAnode PhotoMultiplier Tubes (MAPMTs) as single photon detectors, in view of their use in a ring imaging Cherenkov counter for the CLAS12 spectrometer at the Thomas Jefferson National Accelerator Facility. For this, a laser working at 407.2 nm wavelength was employed. The sample is divided equally into standard window type, with a spectral response in the visible light region, and UV-enhanced window type MAPMTs. The studies confirm the suitability of these MAPMTs for single photon detection in such a Cherenkov imaging application.

  5. Single-photon interference experiment for high schools

    Science.gov (United States)

    Bondani, Maria

    2014-07-01

    We follow the reductio ad absurdum reasoning described in the book "Sneaking a Look at God's Cards" by Giancarlo Ghirardi to demonstrate the wave-particle duality of light in a Mach-Zehnder interferometric setup analog to the conventional Young double-slit experiment. We aim at showing the double nature of light by measuring the existence of interference fringes down to the single-photon level. The setup includes a strongly attenuated laser, polarizing beam splitters, half-waveplates, polarizers and single-photon detectors.

  6. Dynamically reconfigurable directionality of plasmon-based single photon sources

    DEFF Research Database (Denmark)

    Chen, Yuntian; Lodahl, Peter; Koenderink, A. Femius

    2010-01-01

    We propose a plasmon-based reconfigurable antenna to controllably distribute emission from single quantum emitters in spatially separated channels. Our calculations show that crossed particle arrays can split the stream of photons from a single emitter into multiple narrow beams. We predict...... that beams can be switched on and off by switching host refractive index. The design method is based on engineering the dispersion relations of plasmon chains and is generally applicable to traveling wave antennas. Controllable photon delivery has potential applications in classical and quantum communication....

  7. Time correlated single-photon counting and fluorescence spectroscopy

    Science.gov (United States)

    Erdmann, Rainer; Enderlein, Jorg; Wahl, Michael

    2005-12-01

    A comprehensive reference on modern technological aspects of time-correlated single photon counting as used in academic and industrial applications. It thus covers areas that have either been neglected in the current literature, or for which an updated reference is not available. The book focuses on general fundamentals of photon statistics, light sources, and electronics for photon counting, time-correlated photon counting, data analysis, and fluorescence correlation techniques. One whole chapter is also devoted to applications of this universal technique in life sciences, with most of the attention given to fluorescence phenomena. The whole is backed by an appendix offering measurement examples and practical hints for data analysis. For physicists, spectroscopists, chemists, and biochemists.

  8. A single photon resolution integrating chip for microstrip detectors

    Science.gov (United States)

    Mozzanica, A.; Bergamaschi, A.; Dinapoli, R.; Graafsma, H.; Henrich, B.; Kraft, P.; Johnson, I.; Lohmann, M.; Schmitt, B.; Shi, X.

    2011-05-01

    A charge integrating readout chip for silicon strip sensors is currently under development at Paul Sherrer Institut. The goal of the project is to provide a readout system that can sustain, through charge integration and automatic gain switching, the instantaneous many-photon deposition typical of the forthcoming XFEL machines. Nevertheless, a charge integrating readout with single photon sensitivity presents several features that can be exploited in many Synchrotron source applications: the possibility of a higher position resolution, the high photon rate capabilities and the possibility to detect low energy photon. A prototype of the readout chip (ROC) has been integrated with a strip detector and with a dedicated DAQ electronic, and it has been tested at the SYRMEP beam line (ELETTRA, Trieste). This work presents the readout chip and shows the results of the beam line tests in terms of spatial resolution and rate capabilities.

  9. Time stamping of single optical photons with 10 ns resolution

    Science.gov (United States)

    Chakaberia, Irakli; Cotlet, Mircea; Fisher-Levine, Merlin; Hodges, Diedra R.; Nguyen, Jayke; Nomerotski, Andrei

    2017-05-01

    High spatial and temporal resolution are key features for many modern applications, e.g. mass spectrometry, probing the structure of materials via neutron scattering, studying molecular structure, etc.1-5 Fast imaging also provides the capability of coincidence detection, and the further addition of sensitivity to single optical photons with the capability of timestamping them further broadens the field of potential applications. Photon counting is already widely used in X-ray imaging,6 where the high energy of the photons makes their detection easier. TimepixCam is a novel optical imager,7 which achieves high spatial resolution using an array of 256×256 55 μm × 55μm pixels which have individually controlled functionality. It is based on a thin-entrance-window silicon sensor, bump-bonded to a Timepix ASIC.8 TimepixCam provides high quantum efficiency in the optical wavelength range (400-1000 nm). We perform the timestamping of single photons with a time resolution of 20 ns, by coupling TimepixCam to a fast image-intensifier with a P47 phosphor screen. The fast emission time of the P479 allows us to preserve good time resolution while maintaining the capability to focus the optical output of the intensifier onto the 256×256 pixel Timepix sensor area. We demonstrate the capability of the (TimepixCam + image intensifier) setup to provide high-resolution single-photon timestamping, with an effective frame rate of 50 MHz.

  10. Hyperbolic Metamaterial Nano-Resonators Make Poor Single Photon Sources

    CERN Document Server

    Axelrod, Simon; Wong, Herman M K; Helmy, Amr S; Hughes, Stephen

    2016-01-01

    We study the optical properties of quantum dipole emitters coupled to hyperbolic metamaterial nano-resonators using a semi-analytical quasinormal mode approach. We show that coupling to metamaterial nano-resonators can lead to significant Purcell enhancements that are nearly an order of magnitude larger than those of plasmonic resonators with comparable geometry. However, the associated single photon output $\\beta$-factors are extremely low (around 10%), far smaller than those of comparable sized metallic resonators (70%). Using a quasinormal mode expansion of the photon Green function, we describe how the low $\\beta$-factors are due to increased Ohmic quenching arising from redshifted resonances, larger quality factors and stronger confinement of light within the metal. In contrast to current wisdom, these results suggest that hyperbolic metamaterial nano-structures make poor choices for single photon sources.

  11. Protecting single-photon entanglement with practical entanglement source

    Science.gov (United States)

    Zhou, Lan; Ou-Yang, Yang; Wang, Lei; Sheng, Yu-Bo

    2017-06-01

    Single-photon entanglement (SPE) is important for quantum communication and quantum information processing. However, SPE is sensitive to photon loss. In this paper, we discuss a linear optical amplification protocol for protecting SPE. Different from the previous protocols, we exploit the practical spontaneous parametric down-conversion (SPDC) source to realize the amplification, for the ideal entanglement source is unavailable in current quantum technology. Moreover, we prove that the amplification using the entanglement generated from SPDC source as auxiliary is better than the amplification assisted with single photons. The reason is that the vacuum state from SPDC source will not affect the amplification, so that it can be eliminated automatically. This protocol may be useful in future long-distance quantum communications.

  12. Multi-group dynamic quantum secret sharing with single photons

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Hongwei [School of Science and State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Ma, Haiqiang, E-mail: hqma@bupt.edu.cn [School of Science and State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Wei, Kejin [School of Science and State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Yang, Xiuqing [School of Science, Beijing Jiaotong University, Beijing 100044 (China); Qu, Wenxiu; Dou, Tianqi; Chen, Yitian; Li, Ruixue; Zhu, Wu [School of Science and State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876 (China)

    2016-07-15

    In this letter, we propose a novel scheme for the realization of single-photon dynamic quantum secret sharing between a boss and three dynamic agent groups. In our system, the boss can not only choose one of these three groups to share the secret with, but also can share two sets of independent keys with two groups without redistribution. Furthermore, the security of communication is enhanced by using a control mode. Compared with previous schemes, our scheme is more flexible and will contribute to a practical application. - Highlights: • A multi-group dynamic quantum secret sharing with single photons scheme is proposed. • Any one of the groups can be chosen to share secret through controlling the polarization of photons. • Two sets of keys can be shared simultaneously without redistribution.

  13. Advanced active quenching circuits for single-photon avalanche photodiodes

    Science.gov (United States)

    Stipčević, M.; Christensen, B. G.; Kwiat, P. G.; Gauthier, D. J.

    2016-05-01

    Commercial photon-counting modules, often based on actively quenched solid-state avalanche photodiode sensors, are used in wide variety of applications. Manufacturers characterize their detectors by specifying a small set of parameters, such as detection efficiency, dead time, dark counts rate, afterpulsing probability and single photon arrival time resolution (jitter), however they usually do not specify the conditions under which these parameters are constant or present a sufficient description. In this work, we present an in-depth analysis of the active quenching process and identify intrinsic limitations and engineering challenges. Based on that, we investigate the range of validity of the typical parameters used by two commercial detectors. We identify an additional set of imperfections that must be specified in order to sufficiently characterize the behavior of single-photon counting detectors in realistic applications. The additional imperfections include rate-dependence of the dead time, jitter, detection delay shift, and "twilighting." Also, the temporal distribution of afterpulsing and various artifacts of the electronics are important. We find that these additional non-ideal behaviors can lead to unexpected effects or strong deterioration of the system's performance. Specifically, we discuss implications of these new findings in a few applications in which single-photon detectors play a major role: the security of a quantum cryptographic protocol, the quality of single-photon-based random number generators and a few other applications. Finally, we describe an example of an optimized avalanche quenching circuit for a high-rate quantum key distribution system based on time-bin entangled photons.

  14. The physics of nanowire superconducting single-photon detectors

    NARCIS (Netherlands)

    Renema, Jelmer Jan

    2015-01-01

    We investigate the detection mechanism in superconducting single photon detectors via quantum detector tomography. We find that the detection event is caused by diffusion of quasiparticles from the absorption spot, combined with entrance of a vortex. Moreover, we investigate the behaviour of

  15. Purification of single-photon entanglement with linear optics

    OpenAIRE

    Sangouard, Nicolas; Simon, Christoph; Coudreau, Thomas; Gisin, Nicolas

    2008-01-01

    We show that single-photon entangled states of the form |0>|1>+|1>|0> can be purified with a simple linear-optics based protocol, which is eminently feasible with current technology. Besides its conceptual interest, this result is relevant for attractive quantum repeater protocols.

  16. An integrated single photon detector array using porous anodic alumina

    NARCIS (Netherlands)

    Melai, J.; Salm, Cora; Schmitz, Jurriaan; Smits, Sander M.; Visschers, J.L.

    2006-01-01

    Abstract—This paper outlines a single photon sensitive detector array. The detector structure is made via CMOS compatible wafer-scale post-processing. The total system comprises a CMOS imaging chip with charge sensitive pixels, an electron multiplier and a photo-cathode. The electron multiplication

  17. Extent of sensitivity of single photon production to parton distribution ...

    Indian Academy of Sciences (India)

    Extent of sensitivity of single photon production to parton distribution functions. SOMNATH DE. Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700 064, India. E-mail: somvecc@gmail.com. MS received 19 September 2013; accepted 13 December 2013. DOI: 10.1007/s12043-014-0765-y; ePublication: 29 ...

  18. Deterministic Secure Quantum Communication with Collective Detection Using Single Photons

    Science.gov (United States)

    Huang, Wei; Wen, Qiao-Yan; Liu, Bin; Gao, Fei; Chen, Hui

    2012-09-01

    Two novel single-photon deterministic secure quantum communication (DSQC) schemes with collective detection are proposed. One is a two-party DSQC, the other is a DSQC network. In these two schemes, only single-photon source and single-photon measurements are required, which makes the schemes more feasible with present techniques. Apart from this, a detection strategy called collective detection is utilized in our schemes, in which the detection is taken only once after the whole process of particle transmission. Such detection strategy improves the efficiencies of our protocols and also reduces the cost of realization as the message sender only need to perform unitary operations in the whole communication. What's more, the efficiencies of qubits and source capacity are both high since almost all the states can be used to transmit message except the ones used for eavesdropping check and each single photon can carry one bit of information. Finally, we prove the security of the our protocols by using the theorems on quantum operation discrimination.

  19. Single photons, dileptons and hadrons from relativistic heavy ion ...

    Indian Academy of Sciences (India)

    Abstract. The production of single photons in Pb+Pb collisions at the CERN SPS as measured by the WA98 experiment is analysed. A quark gluon plasma is assumed to be formed initially, which expands, cools, hadronizes, and undergoes freeze-out. A rich hadronic equation of state is used and the transverse expansion of ...

  20. Single photons, dileptons and hadrons from relativistic heavy ion ...

    Indian Academy of Sciences (India)

    The production of single photons in Pb+Pb collisions at the CERN SPS as measured by the WA98 experiment is analysed. A quark gluon plasma is assumed to be formed initially, which expands, cools, hadronizes, and undergoes freeze-out. A rich hadronic equation of state is used and the transverse expansion of the ...

  1. Deep-submicron CMOS Single Photon Detectors and Quantum Effects

    NARCIS (Netherlands)

    Karami, M.A.

    2011-01-01

    Quantum parasitic effects and miniaturization of Single Photon Avalanche Diodes in deep-submicron technologies have been studied in this thesis in detail. Tunneling noise and Random Telegraph Signal (RTS) noise have been the main two parasitic effects addressed comprehensively. While the fundamental

  2. Superconducting Single-Photon Detectors for Integrated Quantum Optics

    OpenAIRE

    Kahl, Oliver

    2016-01-01

    This thesis reports on the implementation and characterization of a fully integrated single-photon detector. Several detector circuits are realized and it is shown that the detectors exhibit supreme detection performance over a wide optical spectrum. The detectors' scalability is showcased by the parallel operation of multiple detectors within a single integrated circuit. These demonstrations are essential for future developments in integrated quantum optics.

  3. Single photon detection with self-quenching multiplication

    Science.gov (United States)

    Zheng, Xinyu (Inventor); Cunningham, Thomas J. (Inventor); Pain, Bedabrata (Inventor)

    2011-01-01

    A photoelectronic device and an avalanche self-quenching process for a photoelectronic device are described. The photoelectronic device comprises a nanoscale semiconductor multiplication region and a nanoscale doped semiconductor quenching structure including a depletion region and an undepletion region. The photoelectronic device can act as a single photon detector or a single carrier multiplier. The avalanche self-quenching process allows electrical field reduction in the multiplication region by movement of the multiplication carriers, thus quenching the avalanche.

  4. Trapping a single atom with a fraction of a photon using a photonic crystal nanocavity

    NARCIS (Netherlands)

    van Oosten, D.|info:eu-repo/dai/nl/269286470; Kuipers, L.

    2011-01-01

    We consider the interaction between a single rubidium atom and a photonic crystal nanocavity. Because of the ultrasmall mode volume of the nanocavity, an extremely strong coupling regime can be achieved in which the atom can shift the cavity resonance by many cavity linewidths. We show that this

  5. Multi-photon creation and single-photon annihilation of electron-positron pairs

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Huayu

    2011-04-27

    In this thesis we study multi-photon e{sup +}e{sup -} pair production in a trident process, and singlephoton e{sup +}e{sup -} pair annihilation in a triple interaction. The pair production is considered in the collision of a relativistic electron with a strong laser beam, and calculated within the theory of laser-dressed quantum electrodynamics. A regularization method is developed systematically for the resonance problem arising in the multi-photon process. Total production rates, positron spectra, and relative contributions of different reaction channels are obtained in various interaction regimes. Our calculation shows good agreement with existing experimental data from SLAC, and adds further insights into the experimental findings. Besides, we study the process in a manifestly nonperturbative domain, whose accessibility to future all-optical experiments based on laser acceleration is shown. In the single-photon e{sup +}e{sup -} pair annihilation, the recoil momentum is absorbed by a spectator particle. Various kinematic configurations of the three incoming particles are examined. Under certain conditions, the emitted photon exhibits distinct angular and polarization distributions which could facilitate the detection of the process. Considering an equilibrium relativistic e{sup +}e{sup -} plasma, it is found that the single-photon process becomes the dominant annihilation channel for plasma temperatures above 3 MeV. Multi-particle correlation effects are therefore essential for the e{sup +}e{sup -} dynamics at very high density. (orig.)

  6. Room temperature mid-IR single photon spectral imaging

    DEFF Research Database (Denmark)

    Dam, Jeppe Seidelin; Tidemand-Lichtenberg, Peter; Pedersen, Christian

    2012-01-01

    modern Quantum cascade lasers have evolved as ideal coherent mid-IR excitation sources, simple, low noise, room temperature detectors and imaging systems still lag behind. We address this need presenting a novel, field-deployable, upconversion system for sensitive, 2-D, mid-IR spectral imaging. Measured...... room temperature dark noise is 0.2 photons/spatial element/second, which is a billion times below the dark noise level of cryogenically cooled InSb cameras. Single photon imaging and up to 200 x 100 spatial elements resolution is obtained reaching record high continuous wave quantum efficiency of about...

  7. Fast path and polarization manipulation of telecom wavelength single photons in lithium niobate waveguide devices.

    Science.gov (United States)

    Bonneau, Damien; Lobino, Mirko; Jiang, Pisu; Natarajan, Chandra M; Tanner, Michael G; Hadfield, Robert H; Dorenbos, Sanders N; Zwiller, Val; Thompson, Mark G; O'Brien, Jeremy L

    2012-02-03

    We demonstrate fast polarization and path control of photons at 1550 nm in lithium niobate waveguide devices using the electro-optic effect. We show heralded single photon state engineering, quantum interference, fast state preparation of two entangled photons, and feedback control of quantum interference. These results point the way to a single platform that will enable the integration of nonlinear single photon sources and fast reconfigurable circuits for future photonic quantum information science and technology.

  8. Designs for high-efficiency electrically pumped photonic nanowire single-photon sources

    DEFF Research Database (Denmark)

    Gregersen, Niels; Nielsen, Torben Roland; Mørk, Jesper

    2010-01-01

    We propose and analyze three electrically-pumped nanowire single-photon source structures, which achieve output efficiencies of more than 80%. These structures are based on a quantum dot embedded in a photonic nanowire with carefully tailored ends and optimized contact electrodes. Contrary...... to conventional cavity-based sources, this non-resonant approach provides broadband spontaneous emission control and features an improved fabrication tolerance towards surface roughness and imperfections. Using an element-splitting approach, we analyze the various building blocks of the designs with respect...

  9. Advanced time-correlated single photon counting applications

    CERN Document Server

    Becker, Wolfgang

    2015-01-01

    This book is an attempt to bridge the gap between the instrumental principles of multi-dimensional time-correlated single photon counting (TCSPC) and typical applications of the technique. Written by an originator of the technique and by sucessful users, it covers the basic principles of the technique, its interaction with optical imaging methods and its application to a wide range of experimental tasks in life sciences and clinical research. The book is recommended for all users of time-resolved detection techniques in biology, bio-chemistry, spectroscopy of live systems, live cell microscopy, clinical imaging, spectroscopy of single molecules, and other applications that require the detection of low-level light signals at single-photon sensitivity and picosecond time resolution.

  10. Efficient fiber-coupled single-photon source based on quantum dots in a photonic-crystal waveguide

    DEFF Research Database (Denmark)

    Daveau, Raphaël S.; Balram, Krishna C.; Pregnolato, Tommaso

    2017-01-01

    Many photonic quantum information processing applications would benefit from a high brightness, fiber-coupled source of triggered single photons. Here, we present a fiber-coupled photonic-crystal waveguide (PCWG) singlephoton source relying on evanescent coupling of the light field from a tapered...

  11. Single Microwave Photon Detection with a Trapped Electron

    Directory of Open Access Journals (Sweden)

    April Cridland

    2016-11-01

    Full Text Available We investigate theoretically the use of an electron in a Penning trap as a detector of single microwave photons. At the University of Sussex we are developing a chip Penning trap technology, designed to be integrated within quantum circuits. Microwave photons are guided into the trap and interact with the electron’s quantum cyclotron motion. This is an electric dipole transition, where the near field of the microwave radiation induces quantum jumps of the cyclotron harmonic oscillator. The quantum jumps can be monitored using the continuous Stern-Gerlach effect, providing the quantum non demolition signal of the microwave quanta. We calculate the quantum efficiency of photon detection and discuss the main features and technical challenges for the trapped electron as a quantum microwave sensor.

  12. On-chip single photon filtering and multiplexing in hybrid quantum photonic circuits.

    Science.gov (United States)

    Elshaari, Ali W; Zadeh, Iman Esmaeil; Fognini, Andreas; Reimer, Michael E; Dalacu, Dan; Poole, Philip J; Zwiller, Val; Jöns, Klaus D

    2017-08-30

    Quantum light plays a pivotal role in modern science and future photonic applications. Since the advent of integrated quantum nanophotonics different material platforms based on III-V nanostructures-, colour centers-, and nonlinear waveguides as on-chip light sources have been investigated. Each platform has unique advantages and limitations; however, all implementations face major challenges with filtering of individual quantum states, scalable integration, deterministic multiplexing of selected quantum emitters, and on-chip excitation suppression. Here we overcome all of these challenges with a hybrid and scalable approach, where single III-V quantum emitters are positioned and deterministically integrated in a complementary metal-oxide-semiconductor-compatible photonic circuit. We demonstrate reconfigurable on-chip single-photon filtering and wavelength division multiplexing with a foot print one million times smaller than similar table-top approaches, while offering excitation suppression of more than 95 dB and efficient routing of single photons over a bandwidth of 40 nm. Our work marks an important step to harvest quantum optical technologies' full potential.Combining different integration platforms on the same chip is currently one of the main challenges for quantum technologies. Here, Elshaari et al. show III-V Quantum Dots embedded in nanowires operating in a CMOS compatible circuit, with controlled on-chip filtering and tunable routing.

  13. High-fidelity frequency down-conversion of visible entangled photon pairs with superconducting single-photon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Ikuta, Rikizo; Kato, Hiroshi; Kusaka, Yoshiaki; Yamamoto, Takashi; Imoto, Nobuyuki [Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan); Miki, Shigehito; Yamashita, Taro; Terai, Hirotaka; Wang, Zhen [Advanced ICT Research Institute, National Institute of Information and Communications Technology (NICT), Kobe 651-2492 (Japan); Fujiwara, Mikio; Sasaki, Masahide [Advanced ICT Research Institute, National Institute of Information and Communications Technology (NICT), Koganei, Tokyo 184-8795 (Japan); Koashi, Masato [Photon Science Center, The University of Tokyo, Bunkyo-ku, 113-8656 (Japan)

    2014-12-04

    We experimentally demonstrate a high-fidelity visible-to-telecommunicationwavelength conversion of a photon by using a solid-state-based difference frequency generation. In the experiment, one half of a pico-second visible entangled photon pair at 780 nm is converted to a 1522-nm photon. Using superconducting single-photon detectors with low dark count rates and small timing jitters, we observed a fidelity of 0.93±0.04 after the wavelength conversion.

  14. Automated Characterization of Single-Photon Avalanche Photodiode

    Directory of Open Access Journals (Sweden)

    Aina Mardhiyah M. Ghazali

    2012-01-01

    Full Text Available We report an automated characterization of a single-photon detector based on commercial silicon avalanche photodiode (PerkinElmer C30902SH. The photodiode is characterized by I-V curves at different illumination levels (darkness, 10 pW and 10 µW, dark count rate and photon detection efficiency at different bias voltages. The automated characterization routine is implemented in C++ running on a Linux computer. ABSTRAK: Kami melaporkan pencirian pengesan foton tunggal secara automatik berdasarkan kepada diod foto runtuhan silikon (silicon avalanche photodiode (PerkinElmer C30902SH komersial. Pencirian  diod foto adalah berdasarkan kepada plot arus-voltan (I-V pada tahap pencahayaan yang berbeza (kelam - tanpa cahaya, 10pW, dan 10µW, kadar bacaan latar belakang, kecekapan pengesanan foton pada voltan picuan yang berbeza. Pengaturcaraan C++ digunakan di dalam rutin pencirian automatik melalui komputer dengan sistem pengendalian LINUX.KEYWORDS: avalanche photodiode (APD; single photon detector; photon counting; experiment automation

  15. Conversion from Single Photon to Single Electron Spin Using Electrically Controllable Quantum Dots

    Science.gov (United States)

    Oiwa, Akira; Fujita, Takafumi; Kiyama, Haruki; Allison, Giles; Ludwig, Arne; Wieck, Andreas D.; Tarucha, Seigo

    2017-01-01

    Polarization is a fundamental property of light and could provide various solutions to the development of secure optical communications with high capacity and high speed. In particular, the coherent quantum state conversion between single photons and single electron spins is a prerequisite for long-distance quantum communications and distributed quantum computation. Electrically defined quantum dots have already been proven to be suitable for scalable solid state qubits by demonstrations of single-spin coherent manipulations and two-qubit gate operations. Thus, their capacity for quantum information technologies would be considerably extended by the achievement of entanglement between an electron spin in the quantum dots and a photon. In this review paper, we show the basic technologies for trapping single electrons generated by single photons in quantum dots and for detecting their spins using the Pauli effect with sensitive charge sensors.

  16. An all-silicon single-photon source by unconventional photon blockade.

    Science.gov (United States)

    Flayac, Hugo; Gerace, Dario; Savona, Vincenzo

    2015-06-10

    The lack of suitable quantum emitters in silicon and silicon-based materials has prevented the realization of room temperature, compact, stable, and integrated sources of single photons in a scalable on-chip architecture, so far. Current approaches rely on exploiting the enhanced optical nonlinearity of silicon through light confinement or slow-light propagation, and are based on parametric processes that typically require substantial input energy and spatial footprint to reach a reasonable output yield. Here we propose an alternative all-silicon device that employs a different paradigm, namely the interplay between quantum interference and the third-order intrinsic nonlinearity in a system of two coupled optical cavities. This unconventional photon blockade allows to produce antibunched radiation at extremely low input powers. We demonstrate a reliable protocol to operate this mechanism under pulsed optical excitation, as required for device applications, thus implementing a true single-photon source. We finally propose a state-of-art implementation in a standard silicon-based photonic crystal integrated circuit that outperforms existing parametric devices either in input power or footprint area.

  17. Advanced time-correlated single photon counting techniques

    CERN Document Server

    Becker, Wolfgang

    2005-01-01

    Time-correlated single photon counting (TCSPC) is a remarkable technique for recording low-level light signals with extremely high precision and picosecond-time resolution. TCSPC has developed from an intrinsically time-consuming and one-dimensional technique into a fast, multi-dimensional technique to record light signals. So this reference and text describes how advanced TCSPC techniques work and demonstrates their application to time-resolved laser scanning microscopy, single molecule spectroscopy, photon correlation experiments, and diffuse optical tomography of biological tissue. It gives practical hints about constructing suitable optical systems, choosing and using detectors, detector safety, preamplifiers, and using the control features and optimising the operating conditions of TCSPC devices. Advanced TCSPC Techniques is an indispensable tool for everyone in research and development who is confronted with the task of recording low-intensity light signals in the picosecond and nanosecond range.

  18. Single-photon source based on Rydberg exciton blockade

    Science.gov (United States)

    Khazali, Mohammadsadegh; Heshami, Khabat; Simon, Christoph

    2017-11-01

    Bound states of electron–hole pairs in semiconductors demonstrate a hydrogen-like behavior in their high-lying excited states that are also known as Rydberg exciton states. The strong interaction between excitons in levels with high principal quantum numbers prevents the creation of more than one exciton in a small crystal; resulting in the Rydberg blockade effect. Here, we propose a new kind of solid-state single-photon source based on the recently observed Rydberg blockade effect for excitons in cuprous oxide. Our quantitative estimates based on single and double excitation probability dynamics indicate that GHz rates and values of the second-order correlation function {g}2(0) below the percent level can be simultaneously achievable. These results should pave the way to explore applications of Rydberg excitons in photonic quantum information processing.

  19. Storing single photons emitted by a quantum memory on a highly excited Rydberg state.

    Science.gov (United States)

    Distante, Emanuele; Farrera, Pau; Padrón-Brito, Auxiliadora; Paredes-Barato, David; Heinze, Georg; de Riedmatten, Hugues

    2017-01-19

    Strong interaction between two single photons is a long standing and important goal in quantum photonics. This would enable a new regime of nonlinear optics and unlock several applications in quantum information science, including photonic quantum gates and deterministic Bell-state measurements. In the context of quantum networks, it would be important to achieve interactions between single photons from independent photon pairs storable in quantum memories. So far, most experiments showing nonlinearities at the single-photon level have used weak classical input light. Here we demonstrate the storage and retrieval of a paired single photon emitted by an ensemble quantum memory in a strongly nonlinear medium based on highly excited Rydberg atoms. We show that nonclassical correlations between the two photons persist after retrieval from the Rydberg ensemble. Our result is an important step towards deterministic photon-photon interactions, and may enable deterministic Bell-state measurements with multimode quantum memories.

  20. Single-photon ultrashort-lived radionuclides: symposium proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Paras, P.; Thiessen, J.W. (eds.)

    1985-01-01

    The purpose was to define the current role and state-of-the-art regarding the development, clinical applications, and usefulness of generator-produced single-photon ultrashort-lived radionuclides (SPUSLR's) and to predict their future impact on medicine. Special emphasis was placed on the generator production of iridium-191, gold-195, and krypton-81. This report contains expanded summaries of the included papers. (ACR)

  1. Single-photon imaging inspired by human vision

    Science.gov (United States)

    Mohseni, Hooman

    2008-02-01

    Single photon detectors are regarded as a key enabling technology in a wide range of medical, industrial, and military applications. However, the existing single photon detectors that can operate at or near room temperature have poor efficiency and high noise. Interestingly, the counterparts of these devices in nature, namely the rod cells, have amazingly high efficiency and low noise. In particular, the noise performance of the rod cells is five to six orders of magnitude better than the semiconductor based single photon detectors at room temperature. At Bio-inspired Sensors and Optoelectronics Laboratory, we explored the origin of such a high noise performance, and designed and implemented a novel semiconductor device based on the underlying detection mechanism in the rod cells. Our device shows very promising properties including orders of magnitude higher gain and lower noise compared with the existing devices. More interestingly, the low operating voltage of the device combined with high gain uniformity should allow, for the first time, realization of large imaging arrays with a high internal gain. Such imagers would open new opportunities for novel applications such as quantum ghost imaging.

  2. A Search for Single Photon Events in Neutrino Interactions

    CERN Document Server

    Kullenberg, C.T.; Dimmery, D.; Tian, X.C.; Autiero, D.; Gninenko, S.; Rubbia, A.; Alekhin, S.; Astier, P.; Baldisseri, A.; Baldo-Ceolin, M.; Banner, M.; Bassompierre, G.; Benslama, K.; Besson, N.; Bird, I.; Blumenfeld, B.; Bobisut, F.; Bouchez, J.; Boyd, S.; Bueno, A.; Bunyatov, S.; Camilleri, L.; Cardini, A.; Cattaneo, P.W.; Cavasinni, V.; Cervera-Villanueva, A.; Challis, R.; Chukanov, A.; Collazuol, G.; Conforto, G.; Conta, C.; Contalbrigo, M.; Cousins, R.; Degaudenzi, H.; De Santo, A.; Del Prete, T.; Di Lella, L.; do Couto e Silva, E.; Dumarchez, J.; Ellis, M.; Feldman, G.J.; Ferrari, R.; Ferrère, D.; Flaminio, V.; Fraternali, M.; Gaillard, J.-M.; Gangler, E.; Geiser, A.; Geppert, D.; Gibin, D.; Godley, A.; Gomez-Cadenas, J.-J.; Gosset, J.; Gößling, C.; Gouanère, M.; Grant, A.; Graziani, G.; Guglielmi, A.; Hagner, C.; Hernando, J.; Hurst, P.; Hyett, N.; Iacopini, E.; Joseph, C.; Juget, F.; Kent, N.; Klimov, O.; Kokkonen, J.; Kovzelev, A.; Krasnoperov, A.; Kim, J.J.; Kirsanov, M.; Kulagin, S.; Lacaprara, S.; Lachaud, C.; Lakić, B.; Lanza, A.; La Rotonda, L.; Laveder, M.; Letessier-Selvon, A.; Levy, J.M.; Ling, J.; Linssen, L.; Ljubičic, A.; Long, J.; Lupi, A.; Lyubushkin, V.; Marchionni, A.; Martelli, F.; Méchain, X.; Mendiburu, J.-P.; Meyer, J.-P.; Mezzetto, M.; Moorhead, G.F.; Naumov, D.; Nédélec, P.; Nefedov, Yu.; Nguyen-Mau, C.; Orestano, D.; Pastore, F.; Peak, L.S.; Pennacchio, E.; Pessard, H.; Petti, R.; Placci, A.; Polesello, G.; Pollmann, D.; Polyarush, A.; Poulsen, C.; Popov, B.; Rebuffi, L.; Rico, J.; Riemann, P.; Roda, C.; Salvatore, F.; Samoylov, O.; Schahmaneche, K.; Schmidt, B.; Schmidt, T.; Sconza, A.; Scott, A.M.; Seaton, M.B.; Sevior, M.; Sillou, D.; Soler, F.J.P.; Sozzi, G.; Steele, D.; Stiegler, U.; Stipčević, M.; Stolarczyk, Th.; Tareb-Reyes, M.; Taylor, G.N.; Tereshchenko, V.; Toropin, A.; Touchard, A.-M.; Tovey, S.N.; Tran, M.-T.; Tsesmelis, E.; Ulrichs, J.; Vacavant, L.; Valdata-Nappi, M.; Valuev, V.; Vannucci, F.; Varvell, K.E.; Veltri, M.; Vercesi, V.; Vidal-Sitjes, G.; Vieira, J.-M.; Vinogradova, T.; Weber, F.V.; Weisse, T.; Wilson, F.F.; Winton, L.J.; Wu, Q.; Yabsley, B.D.; Zaccone, H.; Zuber, K.; Zuccon, P.

    2012-01-01

    We present a search for neutrino-induced events containing a single, exclusive photon using data from the NOMAD experiment at the CERN SPS where the average energy of the neutrino flux is $\\simeq 25$ GeV. The search is motivated by an excess of electron-like events in the 200--475 MeV energy region as reported by the MiniBOONE experiment. In NOMAD, photons are identified via their conversion to $e^+e^-$ in an active target embedded in a magnetic field. The background to the single photon signal is dominated by the asymmetric decay of neutral pions produced either in a coherent neutrino-nucleus interaction, or in a neutrino-nucleon neutral current deep inelastic scattering, or in an interaction occurring outside the fiducial volume. All three backgrounds are determined {\\it in situ} using control data samples prior to opening the `signal-box'. In the signal region, we observe {\\bf 155} events with a predicted background of {\\bf 129.2 $\\pm$ 8.5 $\\pm$ 3.3}. We interpret this as null evidence for excess of single...

  3. Photon counting imaging with an electron-bombarded CCD: Towards wide-field time-correlated single photon counting (TCSPC)

    Energy Technology Data Exchange (ETDEWEB)

    Hirvonen, Liisa M.; Jiggins, Stephen; Sergent, Nicolas; Zanda, Gianmarco; Suhling, Klaus, E-mail: klaus.suhling@kcl.ac.uk

    2015-07-01

    Single photon detecting capabilities of an electron-bombarded CCD (EBCCD), where a photon is converted into a photoelectron that is accelerated through a high voltage before hitting the CCD chip, were characterised. The photon event pulse height distribution was found to be linearly dependent on the gain voltage. Based on these results, we propose that a gain voltage sweep during exposure in an EBCCD or EBCMOS camera would allow photon arrival time determination from the photon event pulse height with sub-frame exposure time resolution. This effectively uses an electron-bombarded sensor as a parallel-processing photoelectronic time-to-amplitude converter (TAC), or a 2-dimensional streak camera. Several applications that require timing of photon arrival, including fluorescence lifetime imaging microscopy (FLIM), may benefit from this approach. Moreover, the EBCCD was used on a fluorescence microscope to image fluorescently labelled cells in single photon counting mode.

  4. Directional emission of single photons from small atomic samples

    DEFF Research Database (Denmark)

    Miroshnychenko, Yevhen; V. Poulsen, Uffe; Mølmer, Klaus

    2013-01-01

    We provide a formalism to describe deterministic emission of single photons with tailored spatial and temporal profiles from a regular array of multi-level atoms. We assume that a single collective excitation is initially shared by all the atoms in a metastable atomic state, and that this state i...... is coupled by a classical laser field to an optically excited state which rapidly decays to the ground atomic state. Our model accounts for the different field polarization components via re-absorption and emission of light by the Zeeman manifold of optically excited states....

  5. Determining the quantum expectation value by measuring a single photon

    Science.gov (United States)

    Piacentini, Fabrizio; Avella, Alessio; Rebufello, Enrico; Lussana, Rudi; Villa, Federica; Tosi, Alberto; Gramegna, Marco; Brida, Giorgio; Cohen, Eliahu; Vaidman, Lev; Degiovanni, Ivo P.; Genovese, Marco

    2017-12-01

    One description provides only probabilities for obtaining various eigenvalues of a quantum variable. The eigenvalues and the corresponding probabilities specify the expectation value of a physical observable, which is known to be a statistical property of an ensemble of quantum systems. In contrast to this paradigm, here we demonstrate a method for measuring the expectation value of a physical variable on a single particle, namely, the polarization of a single protected photon. This realization of quantum protective measurements could find applications in the foundations of quantum mechanics and quantum-enhanced measurements.

  6. Single-photon non-linear optics with a quantum dot in a waveguide.

    Science.gov (United States)

    Javadi, A; Söllner, I; Arcari, M; Hansen, S Lindskov; Midolo, L; Mahmoodian, S; Kiršanskė, G; Pregnolato, T; Lee, E H; Song, J D; Stobbe, S; Lodahl, P

    2015-10-23

    Strong non-linear interactions between photons enable logic operations for both classical and quantum-information technology. Unfortunately, non-linear interactions are usually feeble and therefore all-optical logic gates tend to be inefficient. A quantum emitter deterministically coupled to a propagating mode fundamentally changes the situation, since each photon inevitably interacts with the emitter, and highly correlated many-photon states may be created. Here we show that a single quantum dot in a photonic-crystal waveguide can be used as a giant non-linearity sensitive at the single-photon level. The non-linear response is revealed from the intensity and quantum statistics of the scattered photons, and contains contributions from an entangled photon-photon bound state. The quantum non-linearity will find immediate applications for deterministic Bell-state measurements and single-photon transistors and paves the way to scalable waveguide-based photonic quantum-computing architectures.

  7. Apparent superluminal advancement of a single photon far beyond its coherence length

    Energy Technology Data Exchange (ETDEWEB)

    Cialdi, Simone; Boscolo, Ilario; Castelli, Fabrizio; Petrillo, Vittoria [Istituto Nazionale di Fisica Nucleare and Dipartimento di Fisica, Universita di Milano, Via Celoria 16, 20133 Milano (Italy)], E-mail: fabrizio.castelli@mi.infn.it

    2009-02-15

    We present experimental results relative to superluminal propagation based on a single photon traversing an optical system, called a 4f-system, which acts singularly on the photon's spectral component phases. A single photon is created by a continuous wave (CW) laser light down-conversion process. The introduction of a linear spectral phase function will lead to the shift of the photon peak far beyond the coherence length of the photon itself (an apparent superluminal propagation of the photon). Superluminal group velocity detection is done by interferometric measurement of the temporally shifted photon with its correlated untouched reference. The observed superluminal photon propagation complies with causality. The operation of the optical system allows the origin of the apparent superluminal photon velocity to be elucidated. The experiment foresees a superluminal effect with single-photon wavepackets.

  8. Single photon imaging and timing array sensor apparatus and method

    Science.gov (United States)

    Smith, R. Clayton

    2003-06-24

    An apparatus and method are disclosed for generating a three-dimension image of an object or target. The apparatus is comprised of a photon source for emitting a photon at a target. The emitted photons are received by a photon receiver for receiving the photon when reflected from the target. The photon receiver determines a reflection time of the photon and further determines an arrival position of the photon on the photon receiver. An analyzer is communicatively coupled to the photon receiver, wherein the analyzer generates a three-dimensional image of the object based upon the reflection time and the arrival position.

  9. Adaptive Depth Imaging with Single-Photon Detectors

    CERN Document Server

    He, Weiji; Lin, Jie; Shen, Shanshan; Chen, Qian; Gu, Guohua; Zhou, Beibei; Zhang, Ping

    2016-01-01

    For active optical imaging, the use of single-photon detectors could greatly improve the detection sensitivity of the system. However in low light-level, traditional maximum-likelihood based imaging method needs long acquisition time to capture clear three-dimensional (3D) image. To tackle this problem, we present a novel imaging method for depth estimate, which can obtain the accurate depth image in a short acquisition time. We exploit the temporal correlations of signal and avoid building the photon-count histogram of the maximum likelihood depth estimate. Our method can efficiently distinguish signal from noise and adaptively change the dwell time of each pixel. The experiment results demonstrate that we can fast obtain the accurate depth image despite the existence of strong background noise.

  10. Search for single photons from supersymmetric particle production

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, E.; Ford, W.T.; Qi, N.; Read A.L. Jr.; Smith, J.G.; Camporesi, T.; De Sangro, R.; Marini, A.; Peruzzi, I.; Piccolo, M.; Ronga, F.; Blume, H.T.; Hurst, R.B.; Venuti, J.P.; Wald, H.B.; Weinstein, R.; Band, H.R.; Gettner, M.W.; Goderre, G.P.; Meyer, O.A.; Moromisato, J.H.; Polvado, R.O.; Shambroom, W.D.; Sleeman, J.C.; von Goeler, E.; Ash, W.W.; Chadwick, G.B.; Clearwater, S.H.; Coombes, R.W.; Kaye, H.S.; Lau, K.H.; Leedy, R.E.; Lynch, H.L.; Messner, R.L.; Moss, L.J.; Muller, F.; Nelson, H.N.; Ritson, D.M.; Rosenberg, L.J.; Wiser, D.E.; Zdarko, R.W.; Groom, D.E.; Lee, H.Y.; Delfino, M.C.; Heltsley, B.K.; Johnson, J.R.; Lavine, T.L.; Maruyama, T.; Prepost, R.

    1985-03-18

    A search in e/sup +/e/sup -/ annihilation for final states which contain only a single energetic photon has been performed at ..sqrt..s = 29 GeV with the MAC detector at PEP. The upper limit on an anomalous signal has been interpreted in terms of mass limits for supersymmetric particles under the assumption of radiative pair paroduction of either supersymmetric photons or neutrinos. For the supersymmetric electron (e) this limit is m/sub e/>37 GeV/c/sup 2/ at the 90% confidence level if M/sub e//sub L/ = m/sub e//sub R/ and the supersymmetric photo (gamma-tilde) has m/sub gamma-tilde/ = 0.

  11. Single-photon counting multicolor multiphoton fluorescence microscope.

    Science.gov (United States)

    Buehler, Christof; Kim, Ki H; Greuter, Urs; Schlumpf, Nick; So, Peter T C

    2005-01-01

    We present a multicolor multiphoton fluorescence microscope with single-photon counting sensitivity. The system integrates a standard multiphoton fluorescence microscope, an optical grating spectrograph operating in the UV-Vis wavelength region, and a 16-anode photomultiplier tube (PMT). The major technical innovation is in the development of a multichannel photon counting card (mC-PhCC) for direct signal collection from multi-anode PMTs. The electronic design of the mC-PhCC employs a high-throughput, fully-parallel, single-photon counting scheme along with a high-speed electrical or fiber-optical link interface to the data acquisition computer. There is no electronic crosstalk among the detection channels of the mC-PhCC. The collected signal remains linear up to an incident photon rate of 10(8) counts per second. The high-speed data interface offers ample bandwidth for real-time readout: 2 MByte lambda-stacks composed of 16 spectral channels, 256 x 256 pixel image with 12-bit dynamic range can be transferred at 30 frames per second. The modular design of the mC-PhCC can be readily extended to accommodate PMTs of more anodes. Data acquisition from a 64-anode PMT has been verified. As a demonstration of system performance, spectrally resolved images of fluorescent latex spheres and ex-vivo human skin are reported. The multicolor multiphoton microscope is suitable for highly sensitive, real-time, spectrally-resolved three-dimensional imaging in biomedical applications.

  12. Photon-by-Photon Determination of Emission Bursts from Diffusing Single Chromophores

    Science.gov (United States)

    Zhang, Kai; Yang, Haw

    2006-03-01

    Diffusing-type single molecule experiment is expected to provide rich information such as protein conformational distribution, DNA sequencing, ultra-sensitive detection, to name a few. However, its application is greatly limited by the difficulty of extracting the useful information out of the noisy data because of the embedded Poissonian noise. Conventional analysis of such trajectories involves further smoothing the data followed by artificially setting a threshold to distinguish the signal, risking the chance of ignoring the fast transition events along the trajectory. Here we report a statistically robust algorithm, which operates on the trajectory photon by photon, based on the well established sequential test model. A demonstration experiment with the gold nanoparticle diffusing throuth the detection volume shows that our algorithm indeed retrieves more information, relieving the incertitude of artificial placement of bin width and threshold.

  13. Strong single-photon coupling in superconducting quantum magnetomechanics.

    Science.gov (United States)

    Via, Guillem; Kirchmair, Gerhard; Romero-Isart, Oriol

    2015-04-10

    We show that the inductive coupling between the quantum mechanical motion of a superconducting microcantilever and a flux-dependent microwave quantum circuit can attain the strong single-photon nanomechanical coupling regime with feasible experimental parameters. We propose to use a superconducting strip, which is in the Meissner state, at the tip of a cantilever. A pickup coil collects the flux generated by the sheet currents induced by an external quadrupole magnetic field centered at the strip location. The position-dependent magnetic response of the superconducting strip, enhanced by both diamagnetism and demagnetizing effects, leads to a strong magnetomechanical coupling to quantum circuits.

  14. Optimised quantum hacking of superconducting nanowire single-photon detectors

    Science.gov (United States)

    Tanner, Michael G.; Makarov, Vadim; Hadfield, Robert H.

    2014-03-01

    We explore bright-light control of superconducting nanowire single-photon detectors (SNSPDs) in the shunted configuration (a practical measure to avoid latching). In an experiment, we simulate an illumination pattern the SNSPD would receive in a typical quantum key distribution system under hacking attack. We show that it effectively blinds and controls the SNSPD. The transient blinding illumination lasts for a fraction of a microsecond and produces several deterministic fake clicks during this time. This attack does not lead to elevated timing jitter in the spoofed output pulse, and hence does not introduce significant errors. Five different SNSPD chip designs were tested. We consider possible countermeasures to this attack.

  15. Inhomogeneous critical current in nanowire superconducting single-photon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Gaudio, R., E-mail: r.gaudio@tue.nl; Hoog, K. P. M. op ' t; Zhou, Z.; Sahin, D.; Fiore, A. [COBRA Research Institute, Eindhoven University of Technology, P.O. Box 513, NL-5600MB Eindhoven (Netherlands)

    2014-12-01

    A superconducting thin film with uniform properties is the key to realize nanowire superconducting single-photon detectors (SSPDs) with high performance and high yield. To investigate the uniformity of NbN films, we introduce and characterize simple detectors consisting of short nanowires with length ranging from 100 nm to 15 μm. Our nanowires, contrary to meander SSPDs, allow probing the homogeneity of NbN at the nanoscale. Experimental results, endorsed by a microscopic model, show the strongly inhomogeneous nature of NbN films on the sub-100 nm scale.

  16. Ghosting phenomena in single photon counting imagers with Vernier anode.

    Science.gov (United States)

    Yang, Hao; Zhao, Baosheng; Qiurong, Yan; Liu, Yong'an; Hu, Huijun

    2011-02-01

    We provide the ghosting theory of two-dimensional Vernier anode based imagers. The single photon counting detection system based on Vernier anode is constructed. The ghosting, which occurs during the decoding of two-dimensional Vernier anode, and its possible solutions are described in detail. On the basis of the discussion of the decoding algorithm, the ghosting theoretical model is established. Phase conditions on which imaging ghosting can be avoided and the probability distribution function are proposed; the root causes of ghosting of two-dimensional Vernier anode are also discussed.

  17. Heralded Single Photons Based on Spectral Multiplexing and Feed-Forward Control

    Science.gov (United States)

    Grimau Puigibert, M.; Aguilar, G. H.; Zhou, Q.; Marsili, F.; Shaw, M. D.; Verma, V. B.; Nam, S. W.; Oblak, D.; Tittel, W.

    2017-08-01

    We propose and experimentally demonstrate a novel approach to a heralded single-photon source based on spectral multiplexing (SMUX) and feed-forward-based spectral manipulation of photons created by means of spontaneous parametric down-conversion in a periodically poled LiNbO3 crystal. As a proof of principle, we show that our three-mode SMUX increases the heralded single-photon rate compared to that of the individual modes without compromising the quality of the emitted single photons. We project that by adding further modes, our approach can lead to a deterministic single-photon source.

  18. Quantum Information Science with Single Atoms and Photons

    Science.gov (United States)

    Kimble, H. J.

    2003-03-01

    Cavity quantum electrodynamics (QED) offers powerful possibilities for the deterministic control of atom-photon interactions quantum by quantum [1]. Indeed, modern experiments in cavity QED have achieved the exceptional circumstance of strong coupling, for which single quanta can profoundly impact the dynamics of the atom-cavity system. The diverse accomplishments of this field set the stage for advances into yet broader frontiers in quantum information science for which cavity QED offers unique advantages, including the creation of quantum networks [2]. The primary technical challenge on the road toward such scientific goals is the need to trap and localize atoms within a cavity in a setting suitable for strong coupling. Two separate experiments in our group have achieved significant milestones in this quest, namely the real-time trapping and tracking of single atoms in cavity QED [3-5]. In one experiment, an atom is trapped by an auxiliary field that functions as a far-detuned dipole-force trap (FORT) [3,4], with trap lifetime 3s, which should be compared to the nanosecond time scale for internal dynamics of the atom-cavity system. In a second experiment, we rely upon light forces at the single-photon level to trap a single atom within the cavity mode [5]. As illustrated by the movies available at http://www.its.caltech.edu/ qoptics/atomorbits/, these reconstructions reveal single atoms bound in orbit by the mechanical forces associated with single photons, and realize a new form of microscopy. Over the duration of the observation, the sensitivity is near the standard quantum limit for sensing the motion of a Cesium atom. This work is supported by the NSF, by the Caltech MURI for Quantum Networks administered by the ARO, and by the ONR. 1. For a review, see contributions in the Special Issue of Physica Scripta T76 (1998). 2. J. I. Cirac, S. J. van Enk, P. Zoller, H. J. Kimble, and H. Mabuchi, Physica Scripta T76, 223 (1998). 3. J. Ye, D. W. Vernooy, and H. J

  19. Waveguide integrated superconducting single-photon detector for on-chip quantum and spectral photonic application

    Science.gov (United States)

    Kovalyuk, V.; Ferrari, S.; Kahl, O.; Semenov, A.; Lobanov, Yu; Shcherbatenko, M.; Korneev, A.; Pernice, W.; Goltsman, G.

    2017-11-01

    With use of the travelling-wave geometry approach, integrated superconductor-nanophotonic devices based on silicon nitride nanophotonic waveguide with a superconducting NbN-nanowire suited on top of the waveguide were fabricated. NbN-nanowire was operated as a single-photon counting detector with up to 92 % on-chip detection efficiency in the coherent mode, serving as a highly sensitive IR heterodyne mixer with spectral resolution (f/df) greater than 106 in C-band at 1550 nm wavelength.

  20. Efficient fiber-coupled single-photon source based on quantum dots in a photonic-crystal waveguide.

    Science.gov (United States)

    Daveau, Raphaël S; Balram, Krishna C; Pregnolato, Tommaso; Liu, Jin; Lee, Eun H; Song, Jin D; Verma, Varun; Mirin, Richard; Nam, Sae Woo; Midolo, Leonardo; Stobbe, Søren; Srinivasan, Kartik; Lodahl, Peter

    2017-02-20

    Many photonic quantum information processing applications would benefit from a high brightness, fiber-coupled source of triggered single photons. Here, we present a fiber-coupled photonic-crystal waveguide single-photon source relying on evanescent coupling of the light field from a tapered out-coupler to an optical fiber. A two-step approach is taken where the performance of the tapered out-coupler is recorded first on an independent device containing an on-chip reflector. Reflection measurements establish that the chip-to-fiber coupling efficiency exceeds 80 %. The detailed characterization of a high-efficiency photonic-crystal waveguide extended with a tapered out-coupling section is then performed. The corresponding overall single-photon source efficiency is 10.9 % ± 2.3 %, which quantifies the success probability to prepare an exciton in the quantum dot, couple it out as a photon in the waveguide, and subsequently transfer it to the fiber. The applied out-coupling method is robust, stable over time, and broadband over several tens of nanometers, which makes it a highly promising pathway to increase the efficiency and reliability of planar chip-based single-photon sources.

  1. Modeling and Design of High-Efficiency Single-Photon Sources

    DEFF Research Database (Denmark)

    Gregersen, Niels; Nielsen, Per Kær; Mørk, Jesper

    2013-01-01

    Solid-state sources capable of emitting single photons on demand are of great interest in quantum information applications. Ideally, such a source should emit exactly one photon into the collection optics per trigger, the emitted photons should be indistinguishable, and the source should be elect......Solid-state sources capable of emitting single photons on demand are of great interest in quantum information applications. Ideally, such a source should emit exactly one photon into the collection optics per trigger, the emitted photons should be indistinguishable, and the source should...

  2. Ultra-Low Power Optical Transistor Using a Single Quantum Dot Embedded in a Photonic Wire

    DEFF Research Database (Denmark)

    Nguyen, H.A.; Grange, T.; Malik, N.S.

    2017-01-01

    Using a single InAs quantum dot embedded in a GaAs photonic wire, we realize a giant non-linearity between two optical modes to experimentally demonstrate an all-optical transistor triggered by 10 photons.......Using a single InAs quantum dot embedded in a GaAs photonic wire, we realize a giant non-linearity between two optical modes to experimentally demonstrate an all-optical transistor triggered by 10 photons....

  3. Dynamically unpolarized single-photon source in diamond with intrinsic randomness

    OpenAIRE

    Abe, Naofumi; Mitsumori, Yasuyoshi; Sadgrove, Mark; Edamatsu, Keiichi

    2017-01-01

    Polarization is one of the fundamental properties of light, providing numerous applications in science and technology. While ?dynamically unpolarized? single-photon sources are demanded for various quantum applications, such sources have never been explored. Here we demonstrate dynamically unpolarized single-photon emission from a single [111]-oriented nitrogen- vacancy centre in diamond, in which the single-photon stream is unpolarized, exhibiting intrinsic randomness with vanishing polariza...

  4. Doped niobium superconducting nanowire single-photon detectors

    Science.gov (United States)

    Jia, Tao; Kang, Lin; Zhang, Labao; Zhao, Qingyuan; Gu, Min; Qiu, Jian; Chen, Jian; Jin, Biaobing

    2014-09-01

    We designed and fabricated a special doped niobium (Nb*) superconducting nanowire single-photon detector (SNSPD) on MgO substrate. The superconductivity of this ultra-thin Nb* film was further improved by depositing an ultra-thin aluminum nitride protective layer on top. Compared with traditional Nb films, Nb* films present higher T C and J C. We investigated the dependence of the characteristics of devices, such as cut-off wavelength, response bandwidth, and temperature, on their geometrical dimensions. Results indicate that reduction in both the width and thickness of Nb* nanowires extended the cut-off wavelength and improved the sensitivity. The Nb* SNSPD (50 nm width and 4.5 nm thickness) exhibited single-photon sensitivities at 1,310, 1,550, and 2,010 nm. We also demonstrated an enhancement in the detection efficiency by a factor of 10 in its count rate by lowering the working temperature from 2.26 K to 315 mK.

  5. Mitigating radiation damage of single photon detectors for space applications

    Energy Technology Data Exchange (ETDEWEB)

    Anisimova, Elena; Higgins, Brendon L.; Bourgoin, Jean-Philippe [University of Waterloo, Institute for Quantum Computing, Waterloo, ON (Canada); University of Waterloo, Department of Physics and Astronomy, Waterloo, ON (Canada); Cranmer, Miles [University of Waterloo, Institute for Quantum Computing, Waterloo, ON (Canada); Choi, Eric [University of Waterloo, Institute for Quantum Computing, Waterloo, ON (Canada); Magellan Aerospace, Ottawa, ON (Canada); Hudson, Danya; Piche, Louis P.; Scott, Alan [Honeywell Aerospace (formerly COM DEV Ltd.), Ottawa, ON (Canada); Makarov, Vadim [University of Waterloo, Institute for Quantum Computing, Waterloo, ON (Canada); University of Waterloo, Department of Physics and Astronomy, Waterloo, ON (Canada); University of Waterloo, Department of Electrical and Computer Engineering, Waterloo, ON (Canada); Jennewein, Thomas [University of Waterloo, Institute for Quantum Computing, Waterloo, ON (Canada); University of Waterloo, Department of Physics and Astronomy, Waterloo, ON (Canada); Canadian Institute for Advanced Research, Quantum Information Science Program, Toronto, ON (Canada)

    2017-12-15

    Single-photon detectors in space must retain useful performance characteristics despite being bombarded with sub-atomic particles. Mitigating the effects of this space radiation is vital to enabling new space applications which require high-fidelity single-photon detection. To this end, we conducted proton radiation tests of various models of avalanche photodiodes (APDs) and one model of photomultiplier tube potentially suitable for satellite-based quantum communications. The samples were irradiated with 106 MeV protons at doses approximately equivalent to lifetimes of 0.6, 6, 12 and 24 months in a low-Earth polar orbit. Although most detection properties were preserved, including efficiency, timing jitter and afterpulsing probability, all APD samples demonstrated significant increases in dark count rate (DCR) due to radiation-induced damage, many orders of magnitude higher than the 200 counts per second (cps) required for ground-to-satellite quantum communications. We then successfully demonstrated the mitigation of this DCR degradation through the use of deep cooling, to as low as -86 C. This achieved DCR below the required 200 cps over the 24 months orbit duration. DCR was further reduced by thermal annealing at temperatures of +50 to +100 C. (orig.)

  6. Single Photon Counting Performance and Noise Analysis of CMOS SPAD-Based Image Sensors

    Directory of Open Access Journals (Sweden)

    Neale A. W. Dutton

    2016-07-01

    Full Text Available SPAD-based solid state CMOS image sensors utilising analogue integrators have attained deep sub-electron read noise (DSERN permitting single photon counting (SPC imaging. A new method is proposed to determine the read noise in DSERN image sensors by evaluating the peak separation and width (PSW of single photon peaks in a photon counting histogram (PCH. The technique is used to identify and analyse cumulative noise in analogue integrating SPC SPAD-based pixels. The DSERN of our SPAD image sensor is exploited to confirm recent multi-photon threshold quanta image sensor (QIS theory. Finally, various single and multiple photon spatio-temporal oversampling techniques are reviewed.

  7. Single Photon Counting Performance and Noise Analysis of CMOS SPAD-Based Image Sensors.

    Science.gov (United States)

    Dutton, Neale A W; Gyongy, Istvan; Parmesan, Luca; Henderson, Robert K

    2016-07-20

    SPAD-based solid state CMOS image sensors utilising analogue integrators have attained deep sub-electron read noise (DSERN) permitting single photon counting (SPC) imaging. A new method is proposed to determine the read noise in DSERN image sensors by evaluating the peak separation and width (PSW) of single photon peaks in a photon counting histogram (PCH). The technique is used to identify and analyse cumulative noise in analogue integrating SPC SPAD-based pixels. The DSERN of our SPAD image sensor is exploited to confirm recent multi-photon threshold quanta image sensor (QIS) theory. Finally, various single and multiple photon spatio-temporal oversampling techniques are reviewed.

  8. Two-photon interference at telecom wavelengths for time-bin-encoded single photons from quantum-dot spin qubits.

    Science.gov (United States)

    Yu, Leo; Natarajan, Chandra M; Horikiri, Tomoyuki; Langrock, Carsten; Pelc, Jason S; Tanner, Michael G; Abe, Eisuke; Maier, Sebastian; Schneider, Christian; Höfling, Sven; Kamp, Martin; Hadfield, Robert H; Fejer, Martin M; Yamamoto, Yoshihisa

    2015-11-24

    Practical quantum communication between remote quantum memories rely on single photons at telecom wavelengths. Although spin-photon entanglement has been demonstrated in atomic and solid-state qubit systems, the produced single photons at short wavelengths and with polarization encoding are not suitable for long-distance communication, because they suffer from high propagation loss and depolarization in optical fibres. Establishing entanglement between remote quantum nodes would further require the photons generated from separate nodes to be indistinguishable. Here, we report the observation of correlations between a quantum-dot spin and a telecom single photon across a 2-km fibre channel based on time-bin encoding and background-free frequency downconversion. The downconverted photon at telecom wavelengths exhibits two-photon interference with another photon from an independent source, achieving a mean wavepacket overlap of greater than 0.89 despite their original wavelength mismatch (900 and 911 nm). The quantum-networking operations that we demonstrate will enable practical communication between solid-state spin qubits across long distances.

  9. Photon-by-Photon Hidden Markov Model Analysis for Microsecond Single-Molecule FRET Kinetics.

    Science.gov (United States)

    Pirchi, Menahem; Tsukanov, Roman; Khamis, Rashid; Tomov, Toma E; Berger, Yaron; Khara, Dinesh C; Volkov, Hadas; Haran, Gilad; Nir, Eyal

    2016-12-29

    The function of biological macromolecules involves large-scale conformational dynamics spanning multiple time scales, from microseconds to seconds. Such conformational motions, which may involve whole domains or subunits of a protein, play a key role in allosteric regulation. There is an urgent need for experimental methods to probe the fastest of these motions. Single-molecule fluorescence experiments can in principle be used for observing such dynamics, but there is a lack of analysis methods that can extract the maximum amount of information from the data, down to the microsecond time scale. To address this issue, we introduce H 2 MM, a maximum likelihood estimation algorithm for photon-by-photon analysis of single-molecule fluorescence resonance energy transfer (FRET) experiments. H 2 MM is based on analytical estimators for model parameters, derived using the Baum-Welch algorithm. An efficient and effective method for the calculation of these estimators is introduced. H 2 MM is shown to accurately retrieve the reaction times from ∼1 s to ∼10 μs and even faster when applied to simulations of freely diffusing molecules. We further apply this algorithm to single-molecule FRET data collected from Holliday junction molecules and show that at low magnesium concentrations their kinetics are as fast as ∼10 4 s -1 . The new algorithm is particularly suitable for experiments on freely diffusing individual molecules and is readily incorporated into existing analysis packages. It paves the way for the broad application of single-molecule fluorescence to study ultrafast functional dynamics of biomolecules.

  10. Entangled Absorption of a Single Photon with a Single Spin in Diamond

    Science.gov (United States)

    Kosaka, Hideo; Niikura, Naeko

    2015-02-01

    Quantum entanglement, a key resource for quantum information science, is inherent in a solid. It has been recently shown that entanglement between a single optical photon and a single spin qubit in a solid is generated via spontaneous emission. However, entanglement generation by measurement is rather essential for quantum operations. We here show that the physics behind the entangled emission can be time reversed to demonstrate entangled absorption mediated by an inherent spin-orbit entanglement in a single nitrogen vacancy center in diamond. Optical arbitrary spin state preparation and complete spin state tomography reveal the fidelity of the entangled absorption to be 95%. With the entangled emission and absorption of a photon, materials can be spontaneously entangled or swap their quantum state based on the quantum teleportation scheme.

  11. Large-mode-area single-polarization single-mode photonic crystal fiber: design and analysis.

    Science.gov (United States)

    Kumar, Ajeet; Saini, Than Singh; Naik, Kishor Dinkar; Sinha, Ravindra Kumar

    2016-07-01

    A rectangular core photonic crystal fiber structure has been presented and analyzed for single-polarization single-mode operation. Single-polarization is obtained with asymmetric design and by introducing different loss for x-polarization and y-polarization of fundamental modes. Single-polarization single-mode operation of the proposed photonic crystal fiber is investigated in detail by using a full vector finite element method with an anisotropic perfectly matched layer. The variations of the confinement loss and effective mode area of x-polarization and y-polarization of fundamental modes have been simulated by varying the structural parameters of the proposed photonic crystal fiber. At the optimized parameters, confinement loss and effective mode area is obtained as 0.94 dB/m and 60.67  μm2 for y-polarization as well as 26.67 dB/m and 67.23  μm2 for x-polarization of fundamental modes, respectively, at 1.55 μm. Therefore simulation results confirmed that, 0.75 m length of fiber will be sufficient to get a y-polarized fundamental mode with an effective mode area as large as 60.67  μm2.

  12. Efficiency and Coherence of Quantum-Dot Single-Photon Sources

    DEFF Research Database (Denmark)

    Madsen, Marta Arcari

    in a Hong-Ou-Mandel experiment. Finally, we demonstrate that a coherent quantum dot coupled to a photonic crystal waveguide is not only a promising single-photon source, but also a highly nonlinear system sensitive at the single-photon level. By performing resonant transmission measurements through...... on this result, we improved the design of the photonic crystal waveguide, and we characterized in detail the efficiency of the device and the coherence of the emitted single photons. We investigate the decoherence mechanisms affecting the quantum dots by performing resonance fluorescence experiments on emitters...... of a single charge. A very high degree of coherence can be achieved by embedding quantum dots in electrically gated samples. We show that a single quantum dot behaves like a nearly-ideal two-level system in a sample with electrical gates, and single photons emitted up to 1 μs apart show indistinguishability...

  13. Direct Photonic-Plasmonic Coupling and Routing in Single Nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Rouxue; Pausauskie, Peter; Huang, Jiaxing; Yang, Piedong

    2009-10-20

    Metallic nanoscale structures are capable of supporting surface plasmon polaritons (SPPs), propagating collective electron oscillations with tight spatial confinement at the metal surface. SPPs represent one of the most promising structures to beat the diffraction limit imposed by conventional dielectric optics. Ag nano wires have drawn increasing research attention due to 2D sub-100 nm mode confinement and lower losses as compared with fabricated metal structures. However, rational and versatile integration of Ag nanowires with other active and passive optical components, as well as Ag nanowire based optical routing networks, has yet to be achieved. Here, we demonstrate that SPPs can be excited simply by contacting a silver nanowire with a SnO2 nanoribbon that serves both as an unpolarized light source and a dielectric waveguide. The efficient coupling makes it possible to measure the propagation-distance-dependent waveguide spectra and frequency-dependent propagation length on a single Ag nanowire. Furthermore, we have demonstrated prototypical photonic-plasmonic routing devices, which are essential for incorporating low-loss Ag nanowire waveguides as practical components into high-capacity photonic circuits.

  14. Single-photon scattering with counter rotating wave interaction

    Science.gov (United States)

    He, Qi-Kai; Zhu, Wei; Wang, Z. H.; Zhou, D. L.

    2017-07-01

    Recent experiments have pushed the studies on atom-photon interactions to the ultrastrong regime, which motivates the exploration of physics beyond the rotation wave approximation. Here we study the single-photon scattering on a system composed of a coupling cavity array with a two-level atom in the center cavity, which, by varying two outside coupling parameters, corresponds to a model from a supercavity (SC) QED to a waveguide QED with counter rotating wave (CRW) interaction. By applying a time-independent scattering theory based on the bound states in the scattering region, we find that the CRW interaction obviously changes the transmission valley even in the weak atom-cavity coupling regime; in particular, the CRW interaction leads to an inelastic scattering process and a Fano-type resonance, which is directly observed in the crossover from the SC-QED case to the waveguide QED case. Predictably, our findings provide the potential of manipulating the CRW effects in realistic systems and pave the way for the numerical study of very general QED systems.

  15. Room temperature mid-IR single photon spectral imaging

    CERN Document Server

    Dam, Jeppe Seidelin; Tidemand-Lichtenberg, Peter

    2012-01-01

    Spectral imaging and detection of mid-infrared (mid-IR) wavelengths are emerging as an enabling technology of great technical and scientific interest; primarily because important chemical compounds display unique and strong mid-IR spectral fingerprints revealing valuable chemical information. While modern Quantum cascade lasers have evolved as ideal coherent mid-IR excitation sources, simple, low noise, room temperature detectors and imaging systems still lag behind. We address this need presenting a novel, field-deployable, upconversion system for sensitive, 2-D, mid-IR spectral imaging. Measured room temperature dark noise is 0.2 photons/spatial element/second, which is a billion times below the dark noise level of cryogenically cooled InSb cameras. Single photon imaging and up to 200 x 100 spatial elements resolution is obtained reaching record high continuous wave quantum efficiency of about 20 % for polarized incoherent light at 3 \\mum. The proposed method is relevant for existing and new mid-IR applicat...

  16. Single-photon sources for quantum technologies - Results of the joint research project SIQUTE

    DEFF Research Database (Denmark)

    Kück, S.; López, M.; Rodiek, B.

    2017-01-01

    In this presentation, the results of the joint research project “Single-Photon Sources for Quantum Technologies” (SIQUTE) [1] will be presented. The focus will be on the development of absolutely characterized single-photon sources, on the realization of an efficient waveguide-based single...

  17. Dynamically unpolarized single-photon source in diamond with intrinsic randomness

    Science.gov (United States)

    Abe, Naofumi; Mitsumori, Yasuyoshi; Sadgrove, Mark; Edamatsu, Keiichi

    2017-04-01

    Polarization is one of the fundamental properties of light, providing numerous applications in science and technology. While ‘dynamically unpolarized’ single-photon sources are demanded for various quantum applications, such sources have never been explored. Here we demonstrate dynamically unpolarized single-photon emission from a single [111]-oriented nitrogen- vacancy centre in diamond, in which the single-photon stream is unpolarized, exhibiting intrinsic randomness with vanishing polarization correlation between time adjacent photons. These properties not only allow true random number generation, but may also enable fundamental tests in quantum physics.

  18. Athermal avalanche in bilayer superconducting nanowire single-photon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Verma, V. B., E-mail: verma@nist.gov; Lita, A. E.; Stevens, M. J.; Mirin, R. P.; Nam, S. W. [National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305 (United States)

    2016-03-28

    We demonstrate that two superconducting nanowires separated by a thin insulating barrier can undergo an avalanche process. In this process, Joule heating caused by a photodetection event in one nanowire and the associated production of athermal phonons which are transmitted through the barrier cause the transition of the adjacent nanowire from the superconducting to the normal state. We show that this process can be utilized in the fabrication of superconducting nanowire single photon detectors to improve the signal-to-noise ratio, reduce system jitter, maximize device area, and increase the external efficiency over a very broad range of wavelengths. Furthermore, the avalanche mechanism may provide a path towards a superconducting logic element based on athermal gating.

  19. Efficient quantum private comparison employing single photons and collective detection

    Science.gov (United States)

    Liu, Bin; Gao, Fei; Jia, Heng-yue; Huang, Wei; Zhang, Wei-wei; Wen, Qiao-yan

    2013-02-01

    Two efficient quantum private comparison (QPC) protocols are proposed, employing single photons and collective detection. In the proposed protocols, two distrustful parties (Alice and Bob) compare the equivalence of information with the help of a semi-honest third party (TP). Utilizing collective detection, the cost of practical realization is reduced greatly. In the first protocol, TP gains the result of the comparison. While in the second protocol, TP cannot get the comparison result. In both of our protocols, Alice and Bob only need be equipped with unitary operation machines, such as phase plates. So Alice and Bob need not to have the expensive quantum devices, such as qubit generating machine, quantum memory machine and quantum measuring machine. Security of the protocols is ensured by theorems on quantum operation discrimination.

  20. TCAD simulations for a novel single-photon avalanche diode

    Science.gov (United States)

    Jin, Xiangliang; Yang, Jia; Yang, Hongjiao; Tang, Lizhen; Liu, Weihui

    2015-03-01

    A single-photon avalanche diode (SPAD) device with P+-SEN junction, and a low concentration of N-type doping circular virtual guard-ring was presented in this paper. SEN layer of the proposed SPAD has high concentration of N-type doping, causing the SPAD low breakdown voltage (~14.26 V). What's more, an efficient and narrow (about 2μm) guard-ring of the proposed SPAD not only can withstand considerably higher electric fields for preventing edge breakdown, but also offers a little increment in fill factor compared with existing SPADs due to its small area. In addition, some Silvaco TCAD simulations have been done and verify characteristics and performance of the design in this work.

  1. Super-resolution from single photon emission: toward biological application

    Science.gov (United States)

    Moreva, E.; Traina, P.; Forneris, J.; Ditalia Tchernij, S.; Guarina, L.; Franchino, C.; Picollo, F.; Ruo Berchera, I.; Brida, G.; Degiovanni, I. P.; Carabelli, V.; Olivero, P.; Genovese, M.

    2017-08-01

    Properties of quantum light represent a tool for overcoming limits of classical optics. Several experiments have demonstrated this advantage ranging from quantum enhanced imaging to quantum illumination. In this work, experimental demonstration of quantum-enhanced resolution in confocal fluorescence microscopy will be presented. This is achieved by exploiting the non-classical photon statistics of fluorescence emission of single nitrogen-vacancy (NV) color centers in diamond. By developing a general model of super-resolution based on the direct sampling of the kth-order autocorrelation function of the photoluminescence signal, we show the possibility to resolve, in principle, arbitrarily close emitting centers. Finally, possible applications of NV-based fluorescent nanodiamonds in biosensing and future developments will be presented.

  2. Superconductor-superconductor bilayers for enhancing single-photon detection

    Science.gov (United States)

    Ivry, Yachin; Surick, Jonathan J.; Barzilay, Maya; Kim, Chung-Soo; Najafi, Faraz; Kalfon-Cohen, Estelle; Dane, Andrew D.; Berggren, Karl K.

    2017-10-01

    Here, we optimized ultrathin films of granular NbN on SiO2 and of amorphous αW5Si3. We showed that hybrid superconducting nanowire single-photon detectors (SNSPDs) made of 2 nm thick αW5Si3 films over 2 nm thick NbN films exhibit advantageous coexistence of timing (96% quantum efficiency) performance. We discuss the governing mechanism of this hybridization via the proximity effect. Our results demonstrate saturated SNSPDs performance at 1550 nm optical wavelength and suggest that such hybridization can significantly expand the range of available superconducting properties, impacting other nano-superconducting technologies. Lastly, this hybridization may be used to tune properties, such as the amorphous character of superconducting films.

  3. Superconductor-superconductor bilayers for enhancing single-photon detection.

    Science.gov (United States)

    Ivry, Yachin; Surick, Jonathan J; Barzilay, Maya; Kim, Chung-Soo; Najafi, Faraz; Kalfon-Cohen, Estelle; Dane, Andrew D; Berggren, Karl K

    2017-10-27

    Here, we optimized ultrathin films of granular NbN on SiO 2 and of amorphous αW 5 Si 3 . We showed that hybrid superconducting nanowire single-photon detectors (SNSPDs) made of 2 nm thick αW 5 Si 3 films over 2 nm thick NbN films exhibit advantageous coexistence of timing (96% quantum efficiency) performance. We discuss the governing mechanism of this hybridization via the proximity effect. Our results demonstrate saturated SNSPDs performance at 1550 nm optical wavelength and suggest that such hybridization can significantly expand the range of available superconducting properties, impacting other nano-superconducting technologies. Lastly, this hybridization may be used to tune properties, such as the amorphous character of superconducting films.

  4. Estudio de la reserva de perfusión miocárdica mediante tomografía de emisión de fotón único con talio-201 y estrés farmacológico con adenosina trifosfato en pacientes con factores de riesgo cardiovascular

    National Research Council Canada - National Science Library

    Huelmos Rodrigo, Ana; Alegría Ezquerra, Eduardo; Martínez Caro, Diego; José García Velloso, María; Ángel Richter Echevarría, José

    1997-01-01

    ...- nificativamente más bajas en los individuos con factores de riesgo cardiovascular que en los suje- aquellos con enfermedad coronaria, lo que puede sugerir que se encuentran en una etapa precoz de aterosclerosis. STUDY OF MYOCARDIAL PERFUSION RESERVE WITH SINGLE-PHOTON-EMISSION COMPUTED TOMOGRAPHY WITH THALLIUM-201 AND PHARMACOLOGICAL STRESS W...

  5. Efficient fiber-coupled single-photon sources based on quantum dots

    DEFF Research Database (Denmark)

    Daveau, Raphaël Sura

    This thesis presents the study of solid-state quantum emitters in two dierent forms. The rst part of the thesis deals with quantum dot based single-photon sources with an emphasis on ecient photon extraction into an optical ber. The second part of the thesis covers a theoretical study of optical...... refrigeration with coupled quantum wells. Many photonic quantum information processing applications would benet from a highbrightness, ber-coupled source of triggered single photons. This thesis presents a study of such sources based on quantum dots coupled to unidirectional photonic-crystal waveguide devices...

  6. Coherent storage and phase modulation of single hard-x-ray photons using nuclear excitons.

    Science.gov (United States)

    Liao, Wen-Te; Pálffy, Adriana; Keitel, Christoph H

    2012-11-09

    The coherent storage and phase modulation of x-ray single-photon wave packets in the resonant scattering of light off nuclei is theoretically investigated. We show that by switching off and on again the magnetic field in the nuclear sample, phase-sensitive storage of photons in the keV regime can be achieved. Corresponding π phase modulation of the stored photon can be accomplished if the retrieving magnetic field is rotated by 180°. The development of such x-ray single-photon control techniques is a first step towards forwarding quantum optics and quantum information to shorter wavelengths and more compact photonic devices.

  7. Wide-field single photon counting imaging with an ultrafast camera and an image intensifier

    Energy Technology Data Exchange (ETDEWEB)

    Zanda, Gianmarco, E-mail: gianmarco.zanda@kcl.ac.uk [King' s College London, Department of Physics, Strand, London WC2R 2LS (United Kingdom); Sergent, Nicolas; Green, Mark; Levitt, James A. [King' s College London, Department of Physics, Strand, London WC2R 2LS (United Kingdom); Petrasek, Zdenek [Biotechnologisches Zentrum, Technische Universitaet Dresden, Tatzberg 47/49, 01307 Dresden (Germany); Suhling, Klaus, E-mail: klaus.suhling@kcl.ac.uk [King' s College London, Department of Physics, Strand, London WC2R 2LS (United Kingdom)

    2012-12-11

    We are reporting a method for wide-field photon counting imaging using a CMOS camera with a 40 kHz frame rate coupled with a three-stage image intensifier mounted on a standard fluorescence microscope. This system combines high frame rates with single photon sensitivity. The output of the phosphor screen, consisting of single-photon events, is collected by a CMOS camera allowing to create a wide-field image with parallel positional and timing information of each photon. Using a pulsed excitation source and a luminescent sample, the arrival time of hundreds of photons can be determined simultaneously in many pixels with microsecond resolution.

  8. Wide-field single photon counting imaging with an ultrafast camera and an image intensifier

    Science.gov (United States)

    Zanda, Gianmarco; Sergent, Nicolas; Green, Mark; Levitt, James A.; Petrášek, Zdeněk; Suhling, Klaus

    2012-12-01

    We are reporting a method for wide-field photon counting imaging using a CMOS camera with a 40 kHz frame rate coupled with a three-stage image intensifier mounted on a standard fluorescence microscope. This system combines high frame rates with single photon sensitivity. The output of the phosphor screen, consisting of single-photon events, is collected by a CMOS camera allowing to create a wide-field image with parallel positional and timing information of each photon. Using a pulsed excitation source and a luminescent sample, the arrival time of hundreds of photons can be determined simultaneously in many pixels with microsecond resolution.

  9. High Count Rate Single Photon Counting Detector Array Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An optical communications receiver requires efficient and high-rate photon-counting capability so that the information from every photon, received at the aperture,...

  10. Photon counting imaging and centroiding with an electron-bombarded CCD using single molecule localisation software

    Energy Technology Data Exchange (ETDEWEB)

    Hirvonen, Liisa M.; Barber, Matthew J.; Suhling, Klaus, E-mail: klaus.suhling@kcl.ac.uk

    2016-06-01

    Photon event centroiding in photon counting imaging and single-molecule localisation in super-resolution fluorescence microscopy share many traits. Although photon event centroiding has traditionally been performed with simple single-iteration algorithms, we recently reported that iterative fitting algorithms originally developed for single-molecule localisation fluorescence microscopy work very well when applied to centroiding photon events imaged with an MCP-intensified CMOS camera. Here, we have applied these algorithms for centroiding of photon events from an electron-bombarded CCD (EBCCD). We find that centroiding algorithms based on iterative fitting of the photon events yield excellent results and allow fitting of overlapping photon events, a feature not reported before and an important aspect to facilitate an increased count rate and shorter acquisition times.

  11. Setting Single Photon Detectors for Use with an Entangled Photon Distribution System

    Science.gov (United States)

    2017-12-01

    photon pairs, quantum networks, quantum state tomography, detection efficiency, entanglement distribution 16. SECURITY CLASSIFICATION OF: 17...Detection and Measurement of Entangled Photon Pairs 3 3. Experiment Procedure 4 3.1 Physical Setup of Equipment and Identification with EPA Software 4 3.2...Entangled Properties of Entangled Photon Pairs 10 4. Data and Results 11 4.1 Two-Photon Interference 11 4.2 Quantum State Tomography 12 5

  12. Time-Bin-Encoded Boson Sampling with a Single-Photon Device

    Science.gov (United States)

    He, Yu; Ding, X.; Su, Z.-E.; Huang, H.-L.; Qin, J.; Wang, C.; Unsleber, S.; Chen, C.; Wang, H.; He, Y.-M.; Wang, X.-L.; Zhang, W.-J.; Chen, S.-J.; Schneider, C.; Kamp, M.; You, L.-X.; Wang, Z.; Höfling, S.; Lu, Chao-Yang; Pan, Jian-Wei

    2017-05-01

    Boson sampling is a problem strongly believed to be intractable for classical computers, but can be naturally solved on a specialized photonic quantum simulator. Here, we implement the first time-bin-encoded boson sampling using a highly indistinguishable (˜94 %) single-photon source based on a single quantum-dot-micropillar device. The protocol requires only one single-photon source, two detectors, and a loop-based interferometer for an arbitrary number of photons. The single-photon pulse train is time-bin encoded and deterministically injected into an electrically programmable multimode network. The observed three- and four-photon boson sampling rates are 18.8 and 0.2 Hz, respectively, which are more than 100 times faster than previous experiments based on parametric down-conversion.

  13. Efficient Concentration Protocols for the Single-Photon Entanglement State with Polarization Feature

    Directory of Open Access Journals (Sweden)

    Lan Zhou

    2017-03-01

    Full Text Available We propose two efficient entanglement concentration protocols (ECPs for arbitrary less-entangled single-photon entanglement state, in which the photon qubit has the polarization feature. The first ECP is in linear optics, and the second ECP is in nonlinear optics. The two ECPs have some attractive advantages. First, they can preserve the polarization feature of the photon qubit, while all the other existing ECPs for single photon state cannot achieve this goal. Second, they only require one pair of less-entangled single-photon entanglement state and some auxiliary single photons. Third, they only require local operations. Especially, the second ECP can be used repeatedly, which can increase its success probability largely. Based on above properties, our two ECPs, especially the second one may be useful in current and future quantum communication.

  14. Single photon response in GaAs quantum transport devices for photon-spin quantum state transfer

    Energy Technology Data Exchange (ETDEWEB)

    Kutsuwa, T. [CREST, Japan Science and Technology Agency (JST), Kawaguchi, Saitama, 332-0012 (Japan); Arai, K. [CREST, Japan Science and Technology Agency (JST), Kawaguchi, Saitama, 332-0012 (Japan); ERATO-JST, Semiconductor Spintronics, Project, JST (Japan); Shigyo, H.; Kinjo, H.; Edamatsu, K. [Research Institute of Electrical Communication, Tohoku University, Sendai (Japan); Ono, K. [CREST, Japan Science and Technology Agency (JST), Kawaguchi, Saitama, 332-0012 (Japan); Low Temperature Physics Laboratory, RIKEN, Saitama (Japan); Mitsumori, Y.; Kosaka, H. [CREST, Japan Science and Technology Agency (JST), Kawaguchi, Saitama, 332-0012 (Japan); Research Institute of Electrical Communication, Tohoku University, Sendai (Japan)

    2006-07-01

    Quantum information can be stored and manipulated by an electron spin if its state was faithfully transferred from messenger photon qubit. Such a quantum state transfer needs to have a function of conversion from photon polarization to electron spin state and flagging the safe conversion without destroying the spin state. We have achieved single photon response by using a quantum dot as an electron trap and a quantum point contact as a charge sensor on GaAs/AlGaAs-based modulation doped structure. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  15. Evaluation of a fast single-photon avalanche photodiode for measurement of early transmitted photons through diffusive media.

    Science.gov (United States)

    Mu, Ying; Valim, Niksa; Niedre, Mark

    2013-06-15

    We tested the performance of a fast single-photon avalanche photodiode (SPAD) in measurement of early transmitted photons through diffusive media. In combination with a femtosecond titanium:sapphire laser, the overall instrument temporal response time was 59 ps. Using two experimental models, we showed that the SPAD allowed measurement of photon-density sensitivity functions that were approximately 65% narrower than the ungated continuous wave case at very early times. This exceeds the performance that we have previously achieved with photomultiplier-tube-based systems and approaches the theoretical maximum predicted by time-resolved Monte Carlo simulations.

  16. Continuous-Wave Single-Photon Transistor Based on a Superconducting Circuit

    DEFF Research Database (Denmark)

    Kyriienko, Oleksandr; Sørensen, Anders Søndberg

    2016-01-01

    We propose a microwave frequency single-photon transistor which can operate under continuous wave probing and represents an efficient single microwave photon detector. It can be realized using an impedance matched system of a three level artificial ladder-type atom coupled to two microwave cavities...... and the appearance of a photon flux leaving the second cavity through a separate input-output port. The proposal does not require time variation of the probe signals, thus corresponding to a passive version of a single-photon transistor. The resulting device is robust to qubit dephasing processes, possesses low dark...

  17. Photoreactions of Porphyrins Initiated by Deep Ultraviolet Single Photons.

    Science.gov (United States)

    Chen, Jing; Luo, Zhixun; Fu, Hongbing; Yao, Jiannian

    2017-06-22

    The newly built 177 nm all-solid-state deep ultraviolet (DUV) laser photoionization mass spectrometer finds a unique advantage to identify porphyrins that bear ionization energies close to 7.0 eV. We observed dramatic selectivity of tetraphenylporphyrins (TPPs) pertaining to varied photochemical processes initiated by the DUV laser excitation. Single-photon ionization was found dominant for 2H-TPP resulting in a fragmentation-free mass spectrum; photoinduced dehydrogenation was observed for zinc TPP, but both dehydrogenation and demetalation are noted for copper TPP. Along with first-principle calculations, we demonstrate how the photoinduced reactions vary with residual energies of photoionization, highest occupied molecular orbital-lowest unoccupied molecular orbital gaps, donor-acceptor orbital overlaps, single-step barriers, and whether or not there is a major process of structural rearrangement. It is demonstrated that the rotation of benzene ring under proper laser radiation prompts dehydrogenation process; also, metallo-TPPs do not support direct demetalation, but it is selectively accomplishable along with dehydrogenation and successive hydrogenation processes. These findings not only provide insights into the hydrogen atom transfer in porphyrins initiated by ultraviolet laser but also suggest promising applications of the DUV laser in designed synthesis and chemical modification of porphyrins.

  18. Hardy's paradox tested in the spin-orbit Hilbert space of single photons

    OpenAIRE

    Karimi, Ebrahim; Cardano, Filippo; Maffei, Maria; de Lisio, Corrado; Marrucci, Lorenzo; Boyd, Robert W.; Santamato, Enrico

    2014-01-01

    We test experimentally the quantum ``paradox'' proposed by Lucien Hardy in 1993 [Phys. Rev. Lett. 71, 1665 (1993)] by using single photons instead of photon pairs. This is achieved by addressing two compatible degrees of freedom of the same particle, namely its spin angular momentum, determined by the photon polarization, and its orbital angular momentum, a property related to the optical transverse mode. Because our experiment involves a single particle, we cannot use locality to logically e...

  19. Efficient generation of indistinguishable single photons on-demand at telecom wavelengths

    Science.gov (United States)

    Kim, Jehyung; Cai, Tao; Richardson, Christopher; Leavitt, Richard; Waks, Edo

    Highly efficient single photon sources are important building blocks for optical quantum information processing. For practical use and long-distance quantum communication, single photons should have fiber-compatible telecom wavelengths. In addition, most quantum communication applications require high degree of indistinguishability of single photons, such that they exhibit interference on a beam splitter. However, deterministic generation of indistinguishable single photons with high brightness remains a challenging problem in particular at telecom wavelengths. We demonstrate a telecom wavelength source of indistinguishable single photons using an InAs/InP quantum dot in a nanophotonic cavity. To obtain the efficient single quantum dot emission, we employ the higher order mode in L3 photonic crystal cavity that shows a nearly Gaussian transverse mode profile and results in out-coupling efficiency exceeding 46 % and unusual bright single quantum dot emission exceeding 1.5 million counts per second at a detector. We also observe Purcell enhanced spontaneous emission rate as large as 4 and high linear polarization ratio of 0.96 for the coupled dots. Using this source, we generate high purity single photons at 1.3 μm wavelength and demonstrate the indistinguishable nature of the emission using a two-photon interference measurement.

  20. Photon antibunching from a single lithographically defined InGaAs/GaAs quantum dot.

    Science.gov (United States)

    Verma, V B; Stevens, Martin J; Silverman, K L; Dias, N L; Garg, A; Coleman, J J; Mirin, R P

    2011-02-28

    We demonstrate photon antibunching from a single lithographically defined quantum dot fabricated by electron beam lithography, wet chemical etching, and overgrowth of the barrier layers by metalorganic chemical vapor deposition. Measurement of the second-order autocorrelation function indicates g(2)(0)=0.395±0.030, below the 0.5 limit necessary for classification as a single photon source.

  1. Ultrafast downconversion quantum interface for a single quantum dot spin and 1550-nm single-photon channel

    Science.gov (United States)

    Yu, L.; Pelc, J. S.; de Greve, K.; McMahon, P. L.; Fejer, M. M.; Yamamoto, Y.; Maier, S.; Schneider, C.; Kamp, M.; Hofling, S.; Forchel, A.; Natarajan, C. M.; Hadfield, R. H.

    2013-03-01

    Long-distance quantum communication networks require appropriate interfaces between matter qubit-based nodes and low-loss photonic quantum channels. Quantum frequency conversion (QFC), whereby a photonic qubit's carrier frequency is translated while maintaining its quantum state, is well-suited to the task. Quantum dots have been studied extensively as potential quantum network nodes, but they do not emit indistinguishable single photons at telecomm wavelengths. We report an ultrafast, low-noise downconversion quantum interface, in which 910-nm single photons from a quantum dot are downconverted to the 1.5- μm lowest-loss telecom band, showing near-perfect preservation of antibunched photon statistics. Moreover, the resulting time resolution could also improve photon indistinguishability. Together with the III-V semiconductor quantum dot spin system, this ultrafast downconversion quantum interface provides new possibility to realize long-distance quantum communication networks.

  2. Low-noise low-jitter 32-pixels CMOS single-photon avalanche diodes array for single-photon counting from 300 nm to 900 nm

    Energy Technology Data Exchange (ETDEWEB)

    Scarcella, Carmelo; Tosi, Alberto, E-mail: alberto.tosi@polimi.it; Villa, Federica; Tisa, Simone; Zappa, Franco [Politecnico di Milano, Dipartimento di Elettronica, Informazione e Bioingegneria, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy)

    2013-12-15

    We developed a single-photon counting multichannel detection system, based on a monolithic linear array of 32 CMOS SPADs (Complementary Metal-Oxide-Semiconductor Single-Photon Avalanche Diodes). All channels achieve a timing resolution of 100 ps (full-width at half maximum) and a photon detection efficiency of 50% at 400 nm. Dark count rate is very low even at room temperature, being about 125 counts/s for 50 μm active area diameter SPADs. Detection performance and microelectronic compactness of this CMOS SPAD array make it the best candidate for ultra-compact time-resolved spectrometers with single-photon sensitivity from 300 nm to 900 nm.

  3. Experimental single photon exchange along a space link of 7000 km

    DEFF Research Database (Denmark)

    Dequal, Daniele; Vallone, Giuseppe; Bacco, Davide

    2015-01-01

    Extending the single photon transmission distance is a basic requirement for the implementation of quantum communication on a global scale. In this work we report the single photon exchange from a medium Earth orbit satellite (MEO) at more than 7000 km of slanted distance to the ground station...... at the Matera Laser Ranging Observatory. The single photon transmitter was realized by exploiting the corner cube retro-reflectors mounted on the LAGEOS-2 satellite. Long duration of data collection is possible with such altitude, up to 43 minutes in a single passage. The mean number of photons per pulse (µsat......) has been limited to 1 for 200 seconds, resulting in an average detection rate of 3.0 cps and a signal to noise ratio of 1.5. The feasibility of single photon exchange from MEO satellites paves the way to tests of Quantum Mechanics in moving frames and to global Quantum Information....

  4. Temporal and spatial multiplexed infrared single-photon counter based on high-speed avalanche photodiode.

    Science.gov (United States)

    Chen, Xiuliang; Ding, Chengjie; Pan, Haifeng; Huang, Kun; Laurat, Julien; Wu, Guang; Wu, E

    2017-03-15

    We report on a high-speed temporal and spatial multiplexed single-photon counter with photon-number-resolving capability up to four photons. The infrared detector combines a fiber loop to split, delay and recombine optical pulses and a 200 MHz dual-channel single-photon detector based on InGaAs/InP avalanche photodiode. To fully characterize the photon-number-resolving capability, we perform quantum detector tomography and then reconstruct its positive-operator-valued measure and the associated Wigner functions. The result shows that, despite of the afterpulsing noise and limited system detection efficiency, this temporal and spatial multiplexed single-photon counter can already find applications for large repetition rate quantum information schemes.

  5. Quantum nonlinear optics with single photons enabled by strongly interacting atoms.

    Science.gov (United States)

    Peyronel, Thibault; Firstenberg, Ofer; Liang, Qi-Yu; Hofferberth, Sebastian; Gorshkov, Alexey V; Pohl, Thomas; Lukin, Mikhail D; Vuletić, Vladan

    2012-08-02

    The realization of strong nonlinear interactions between individual light quanta (photons) is a long-standing goal in optical science and engineering, being of both fundamental and technological significance. In conventional optical materials, the nonlinearity at light powers corresponding to single photons is negligibly weak. Here we demonstrate a medium that is nonlinear at the level of individual quanta, exhibiting strong absorption of photon pairs while remaining transparent to single photons. The quantum nonlinearity is obtained by coherently coupling slowly propagating photons to strongly interacting atomic Rydberg states in a cold, dense atomic gas. Our approach paves the way for quantum-by-quantum control of light fields, including single-photon switching, all-optical deterministic quantum logic and the realization of strongly correlated many-body states of light.

  6. Quantum nonlinear optics with single photons enabled by strongly interacting atoms

    DEFF Research Database (Denmark)

    Peyronel, Thibault; Firstenberg, Ofer; Liang, Qi Yu

    2012-01-01

    The realization of strong nonlinear interactions between individual light quanta (photons) is a long-standing goal in optical science and engineering, being of both fundamental and technological significance. In conventional optical materials, the nonlinearity at light powers corresponding...... to single photons is negligibly weak. Here we demonstrate a medium that is nonlinear at the level of individual quanta, exhibiting strong absorption of photon pairs while remaining transparent to single photons. The quantum nonlinearity is obtained by coherently coupling slowly propagating photons...... to strongly interacting atomic Rydberg states in a cold, dense atomic gas. Our approach paves the way for quantum-by-quantum control of light fields, including single-photon switching, all-optical deterministic quantum logic and the realization of strongly correlated many-body states of light....

  7. Cavity enhanced telecom heralded single photons for spin-wave solid state quantum memories

    Science.gov (United States)

    Rieländer, Daniel; Lenhard, Andreas; Mazzera, Margherita; de Riedmatten, Hugues

    2016-12-01

    We report on a source of heralded narrowband (≈ 3 MHz) single photons compatible with solid-state spin-wave quantum memories based on praseodymium doped crystals. Widely non-degenerate narrow-band photon pairs are generated using cavity enhanced down conversion. One photon from the pair is at telecom wavelengths and serves as heralding signal, while the heralded single photon is at 606 nm, resonant with an optical transition of Pr3+:Y2SiO5. The source offers a heralding efficiency of 28% and a generation rate exceeding 2000 pairs mW-1 in a single-mode. The single photon nature of the heralded field is confirmed by a direct antibunching measurement, with a measured antibunching parameter down to 0.010(4). Moreover, we investigate in detail photon cross- and autocorrelation functions proving non-classical correlations between the two photons. The results presented in this paper offer prospects for the demonstration of single photon spin-wave storage in an on-demand solid state quantum memory, heralded by a telecom photon.

  8. Single Photon Emission Tomography Imaging in Parkinsonian Disorders: A Review

    Directory of Open Access Journals (Sweden)

    Paul D. Acton

    2000-01-01

    Full Text Available Parkinsonian symptoms are associated with a number of neurodegenerative disorders, such as Parkinson’s disease, multiple system atrophy and progressive supranuclear palsy. Pathological evidence has shown clearly that these disorders are associated with a loss of neurons, particularly in the nigrostriatal dopaminergic pathway. Positron emission tomography (PET and single photon emission tomography (SPECT now are able to visualise and quantify changes in cerebral blood flow, glucose metabolism, and dopaminergic function produced by parkinsonian disorders. Both PET and SPECT have become important tools in the differential diagnosis of these diseases, and may have sufficient sensitivity to detect neuronal changes before the onset of clinical symptoms. Imaging is now being utilised to elucidate the genetic contribution to Parkinson’s disease, and in longitudinal studies to assess the efficacy and mode of action of neuroprotective drug and surgical treatments. This review summarises recent applications of SPECT imaging in the study of parkinsonian disorders, with particular reference to the increasing role it is playing in the understanding, diagnosis and management of these diseases.

  9. Brain single photon emission computed tomography in neonates

    Energy Technology Data Exchange (ETDEWEB)

    Denays, R.; Van Pachterbeke, T.; Tondeur, M.; Spehl, M.; Toppet, V.; Ham, H.; Piepsz, A.; Rubinstein, M.; Nol, P.H.; Haumont, D. (Free Universities of Brussels (Belgium))

    1989-08-01

    This study was designed to rate the clinical value of ({sup 123}I)iodoamphetamine (IMP) or ({sup 99m}Tc) hexamethyl propylene amine oxyme (HM-PAO) brain single photon emission computed tomography (SPECT) in neonates, especially in those likely to develop cerebral palsy. The results showed that SPECT abnormalities were congruent in most cases with structural lesions demonstrated by ultrasonography. However, mild bilateral ventricular dilatation and bilateral subependymal porencephalic cysts diagnosed by ultrasound were not associated with an abnormal SPECT finding. In contrast, some cortical periventricular and sylvian lesions and all the parasagittal lesions well visualized in SPECT studies were not diagnosed by ultrasound scans. In neonates with subependymal and/or intraventricular hemorrhage the existence of a parenchymal abnormality was only diagnosed by SPECT. These results indicate that ({sup 123}I)IMP or ({sup 99m}Tc)HM-PAO brain SPECT shows a potential clinical value as the neurodevelopmental outcome is clearly related to the site, the extent, and the number of cerebral lesions. Long-term clinical follow-up is, however, mandatory in order to define which SPECT abnormality is associated with neurologic deficit.

  10. Tracking hidden objects with a single-photon camera

    CERN Document Server

    Gariepy, Genevieve; Henderson, Robert; Leach, Jonathan; Faccio, Daniele

    2015-01-01

    The ability to know what is hidden around a corner or behind a wall provides a crucial advantage when physically going around the obstacle is impossible or dangerous. Previous solutions to this challenge were constrained e.g. by their physical size, the requirement of reflective surfaces or long data acquisition times. These impede both the deployment of the technology outside the laboratory and the development of significant advances, such as tracking the movement of large-scale hidden objects. We demonstrate a non-line-of-sight laser ranging technology that relies upon the ability, using only a floor surface, to send and detect light that is scattered around an obstacle. A single-photon avalanche diode (SPAD) camera detects light back-scattered from a hidden object that can then be located with centimetre precision, simultaneously tracking its movement. This non-line-of-sight laser ranging system is also shown to work at human length scales, paving the way for a variety of real-life situations.

  11. Proposal for automated transformations on single-photon multipath qudits

    Science.gov (United States)

    Baldijão, R. D.; Borges, G. F.; Marques, B.; Solís-Prosser, M. A.; Neves, L.; Pádua, S.

    2017-09-01

    We propose a method for implementing automated state transformations on single-photon multipath qudits encoded in a one-dimensional transverse spatial domain. It relies on transferring the encoding from this domain to the orthogonal one by applying a spatial phase modulation with diffraction gratings, merging all the initial propagation paths by using a stable interferometric network, and filtering out the unwanted diffraction orders. The automation feature is attained by utilizing a programmable phase-only spatial light modulator (SLM) where properly designed diffraction gratings displayed on its screen will implement the desired transformations, including, among others, projections, permutations, and random operations. We discuss the losses in the process which is, in general, inherently nonunitary. Some examples of transformations are presented and, considering a realistic scenario, we analyze how they will be affected by the pixelated structure of the SLM screen. The method proposed here enables one to implement much more general transformations on multipath qudits than is possible with a SLM alone operating in the diagonal basis of which-path states. Therefore, it will extend the range of applicability for this encoding in high-dimensional quantum information and computing protocols as well as fundamental studies in quantum theory.

  12. Proceedings of clinical SPECT (single photon emission computed tomography) symposium

    Energy Technology Data Exchange (ETDEWEB)

    1986-09-01

    It has been five years since the last in-depth American College of Nuclear Physicians/Society of Nuclear Medicine Symposium on the subject of single photon emission computed tomography (SPECT) was held. Because this subject was nominated as the single most desired topic we have selected SPECT imaging as the basis for this year's program. The objectives of this symposium are to survey the progress of SPECT clinical applications that have taken place over the last five years and to provide practical and timely guidelines to users of SPECT so that this exciting imaging modality can be fully integrated into the evaluation of pathologic processes. The first half was devoted to a consideration of technical factors important in SPECT acquisition and the second half was devoted to those organ systems about which sufficient clinical SPECT imaging data are available. With respect to the technical aspect of the program we have selected the key areas which demand awareness and attention in order to make SPECT operational in clinical practice. These include selection of equipment, details of uniformity correction, utilization of phantoms for equipment acceptance and quality assurance, the major aspect of algorithms, an understanding of filtered back projection and appropriate choice of filters and an awareness of the most commonly generated artifacts and how to recognize them. With respect to the acquisition and interpretation of organ images, the faculty will present information on the major aspects of hepatic, brain, cardiac, skeletal, and immunologic imaging techniques. Individual papers are processed separately for the data base. (TEM)

  13. Time-gating scheme based on a photodiode for single-photon counting

    Science.gov (United States)

    Kumavor, Patrick D.; Tavakoli, Behnoosh; Donkor, Eric; Zhu, Quing

    2012-01-01

    A fast, simple, and low-cost optical time-gating scheme for counting single photons is presented. Its construction consists of a silicon photodiode connected in series with a 50 Ω resistor and that operates in the photoconductive mode. The temporal resolution at the FWHM of the photon counting system was measured to be 62 ps. The profile of a single-photon pulse measured with the counting system agreed well with analytical results. The system was also used to successfully resolve a pair of targets with 4 mm separation inside a highly scattering medium by the use of time-gated early-arriving photons. PMID:21725458

  14. Temporal Purity and Quantum Interference of Single Photons from Two Independent Cold Atomic Ensembles.

    Science.gov (United States)

    Qian, Peng; Gu, Zhenjie; Cao, Rong; Wen, Rong; Ou, Z Y; Chen, J F; Zhang, Weiping

    2016-07-01

    The temporal purity of single photons is crucial to the indistinguishability of independent photon sources for the fundamental study of the quantum nature of light and the development of photonic technologies. Currently, the technique for single photons heralded from time-frequency entangled biphotons created in nonlinear crystals does not guarantee the temporal-quantum purity, except using spectral filtering. Nevertheless, an entirely different situation is anticipated for narrow-band biphotons with a coherence time far longer than the time resolution of a single-photon detector. Here we demonstrate temporally pure single photons with a coherence time of 100 ns, directly heralded from the time-frequency entangled biphotons generated by spontaneous four-wave mixing in cold atomic ensembles, without any supplemented filters or cavities. A near-perfect purity and indistinguishability are both verified through Hong-Ou-Mandel quantum interference using single photons from two independent cold atomic ensembles. The time-frequency entanglement provides a route to manipulate the pure temporal state of the single-photon source.

  15. Tomography of a Mode-Tunable Coherent Single-Photon Subtractor

    Directory of Open Access Journals (Sweden)

    Young-Sik Ra

    2017-07-01

    Full Text Available Single-photon subtraction plays important roles in optical quantum information processing as it provides a non-Gaussian characteristic in continuous-variable quantum information. While the conventional way of implementing single-photon subtraction based on a low-reflectance beam splitter works properly for a single-mode quantum state, it is unsuitable for a multimode quantum state because a single photon is subtracted from all multiple modes without maintaining their mode coherence. Here, we experimentally implement and characterize a mode-tunable coherent single-photon subtractor based on sum-frequency generation. It can subtract a single photon exclusively from one desired time-frequency mode of light or from a coherent superposition of multiple time-frequency modes. To experimentally characterize the time-frequency modes of the single-photon subtractor, we employ quantum process tomography based on coherent states. The mode-tunable coherent single-photon subtractor will be an essential element for realizing non-Gaussian quantum networks necessary to get a quantum advantage in information processing.

  16. Efficient out-coupling of high-purity single photons from a coherent quantum dot in a photonic-crystal cavity

    DEFF Research Database (Denmark)

    Madsen, Kristian Høeg; Ates, Serkan; Liu, J.

    2014-01-01

    We demonstrate a single-photon collection efficiency of (44.3 ± 2.1)% from a quantum dot in a low-Q mode of a photonic-crystal cavity with a single-photon purity of g(2)(0) = (4 ± 5)% recorded above the saturation power. The high efficiency is directly confirmed by detecting up to 962 ± 46...... kilocounts per second on a single-photon detector on another quantum dot coupled to the cavity mode. The high collection efficiency is found to be broadband, as is explained by detailed numerical simulations. Cavity-enhanced efficient excitation of quantum dots is obtained through phonon-mediated excitation...... and under these conditions, single-photon indistinguishability measurements reveal long coherence times reaching 0.77 ± 0.19 ns in a weak-excitation regime. Our work demonstrates that photonic crystals provide a very promising platform for highly integrated generation of coherent single photons including...

  17. EQUIPMENTS TO SINGLE PHOTON REGISTRATION. PART 1. FEATURES AND POSSIBILITIES OF MULTI-CHANNEL PHOTODETECTORS WITH INTRINSIC AMPLIFICATION. (REVIEW

    Directory of Open Access Journals (Sweden)

    O. V. Dvornikov

    2012-01-01

    Full Text Available The main types of the modern photo detectors applied to single photon registration are analyzed. It is offered to use silicon photomultipliers for production of multi-channel optoelectronic systems with the single photon resolution.

  18. Room-temperature single-photon generation from solitary dopants of carbon nanotubes

    Science.gov (United States)

    Ma, Xuedan; Hartmann, Nicolai F.; Baldwin, Jon K. S.; Doorn, Stephen K.; Htoon, Han

    2015-08-01

    On-demand single-photon sources capable of operating at room temperature and the telecom wavelength range of 1,300-1,500 nm hold the key to the realization of novel technologies that span from sub-diffraction imaging to quantum key distribution and photonic quantum information processing. Here, we show that incorporation of undoped (6,5) single-walled carbon nanotubes into a SiO2 matrix can lead to the creation of solitary oxygen dopant states capable of fluctuation-free, room-temperature single-photon emission in the 1,100-1,300 nm wavelength range. We investigated the effects of temperature on photoluminescence emission efficiencies, fluctuations and decay dynamics of the dopant states and determined the conditions most suitable for the observation of single-photon emission. This emission can in principle be extended to 1,500 nm by doping of smaller-bandgap single-walled carbon nanotubes. This easy tunability presents a distinct advantage over existing defect centre single-photon emitters (for example, diamond defect centres). Our SiO2-encapsulated sample also presents exciting opportunities to apply Si/SiO2-based micro/nano-device fabrication techniques in the development of electrically driven single-photon sources and integration of these sources into quantum photonic devices and networks.

  19. Photon emission statistics and photon tracking in single-molecule spectroscopy of molecular aggregates : Dimers and trimers

    NARCIS (Netherlands)

    Bloemsma, E. A.; Knoester, J.

    2012-01-01

    Based on the generating function formalism, we investigate broadband photon statistics of emission for single dimers and trimers driven by a continuous monochromatic laser field. In particular, we study the first and second moments of the emission statistics, which are the fluorescence excitation

  20. Myocardial perfusion single photon emission computed tomography in asymptomatic diabetics.

    Science.gov (United States)

    Harshad, K; Sathyamurthy, I; Ashish, G; Padma, D; Shelley, S; Indirani, M; Subramanian, K

    2010-01-01

    Coronary artery disease (CAD) is the most important cause of mortality in diabetic patients. Diabetes mellitus (DM) due to autonomic neuropathy leads to asymptomatic CAD. Hence, it is important to screen the patients with DM for CAD. To study the prevalence of asymptomatic CAD by Myocardial Perfuision SPECT (Single Photon Emission Computed Tomography) (MPS) in diabetics. This prospective study included 88 asymptomatic patients (58 males and 30 females) of Type 2 DM of more than 5 years duration in the age group of 40-65 years. Risk factors like hypertension, dyslipidemia, smoking, family history of CAD and Body Mass Index > or = 25 kg/sq.m were assessed. All these patients underwent MPS study as two day standard protocol. Thirty eight patients underwent invasive Coronary Angiography (CAG) and stenosis greater than 50% was considered significant. Abnormal perfusion was detected in 38 (43%) diabetics and 4 (11%) controls. A total of 81 perfusion defects were identified (19 fired and 62 reversible). CAG showed significant coronary stenosis in 26 (68.4%), insignificant in 8 (21%) and no stenosis in 4 (10.6%) patients. A total of 114 coronaries were analysed, significant stenosis in 67 (58.8%) coronaries, 21 (18.4%) had insignificant lesions and 26(22.8%) were normal. In comparison to CAG, MPS had sensitivity of 86.6% and specificity of 51%. The Myocardial Perfusion SPECT is a sensitive diagnostic tool to identify ischemia in asymptomatic diabetics. MPS can be used as screening test for risk stratification. It has a prognostic value in predicting the outcome of CAD and can be useful for long-term follow up too.

  1. Large-area single-mode photonic bandgap vcsels

    DEFF Research Database (Denmark)

    Birkedal, Dan; Gregersen, N.; Bischoff, S.

    2003-01-01

    We demonstrate that the photonic bandgap effect can be used to control the modes of large area vertical cavity surface emitting lasers. We obtain more than 20 dB side mode suppression ratios in a 10-micron area device....

  2. Photonic waveguides evanescently coupled with single NV-centers

    OpenAIRE

    Liebermeister, Lars

    2015-01-01

    The interaction of photons with individual quantum systems is a very fundamental process in physics. Thereby, the emission rate as well as the angular emission pattern of a quantum emitter are not only a function of intrinsic properties of the emitter itself, but are also strongly modified by its surrounding. For instance, by restricting the optical modes which are allowed at the position of the dipole, the emission rate can be strongly modified and the emitted photons can be directed into sp...

  3. Single Mode Photonic Crystal Vertical Cavity Surface Emitting Lasers

    Directory of Open Access Journals (Sweden)

    Kent D. Choquette

    2012-01-01

    Full Text Available We review the design, fabrication, and performance of photonic crystal vertical cavity surface emitting lasers (VCSELs. Using a periodic pattern of etched holes in the top facet of the VCSEL, the optical cavity can be designed to support the fundamental mode only. The electrical confinement is independently defined by proton implantation or oxide confinement. By control of the refractive index and loss created by the photonic crystal, operation in the Gaussian mode can be insured, independent of the lasing wavelength.

  4. Scattering of a single photon on a two-qubit structure with resonators

    Science.gov (United States)

    Sultanov, A. N.; Karpov, D. S.; Greenberg, Y. S.; Shevchenko, S. N.; Shtygashev, A. A.

    2017-07-01

    In this paper, the scattering of a single photon in a waveguide-resonator-qubit system is studied. An open waveguide is connected to two resonators, located at an arbitrary distance from each other and containing a single qubit each. The scattering of a single photon makes it possible to describe the behavior of the system completely quantum mechanically. We show the existence of Fano resonance, which is a direct manifestation of the interference between the incident photon and virtual photons associated with transitions between the states of the system. The obtained expressions for the transmission coefficients allowed us to take into account the influence of the incident photon frequency on the resonances and their widths.

  5. Efficient single-photon frequency conversion in the microwave domain using superconducting quantum circuits

    Science.gov (United States)

    Jia, W. Z.; Wang, Y. W.; Liu, Yu-xi

    2017-11-01

    We present an approach to achieve efficient single-photon frequency conversion in the microwave domain based on coherent control in superconducting quantum circuits, which consist of a driven artificial atom coupled to a semi-infinite transmission line. Using the full quantum-mechanical method, we analyze the single-photon scattering process in this system and find that single-photon frequency up- or down-conversion with efficiency close to unity can be achieved by adjusting the parameters of the control field applied to the artificial atom. We further show that our approach is experimentally feasible in currently available superconducting flux qubit circuits.

  6. Spin-based single-photon transistor, dynamic random access memory, diodes, and routers in semiconductors

    Science.gov (United States)

    Hu, C. Y.

    2016-12-01

    The realization of quantum computers and quantum Internet requires not only quantum gates and quantum memories, but also transistors at single-photon levels to control the flow of information encoded on single photons. Single-photon transistor (SPT) is an optical transistor in the quantum limit, which uses a single photon to open or block a photonic channel. In sharp contrast to all previous SPT proposals which are based on single-photon nonlinearities, here I present a design for a high-gain and high-speed (up to THz) SPT based on a linear optical effect: giant circular birefringence induced by a single spin in a double-sided optical microcavity. A gate photon sets the spin state via projective measurement and controls the light propagation in the optical channel. This spin-cavity transistor can be directly configured as diodes, routers, DRAM units, switches, modulators, etc. Due to the duality as quantum gate and transistor, the spin-cavity unit provides a solid-state platform ideal for future Internet: a mixture of all-optical Internet with quantum Internet.

  7. Efficient multi-mode to single-mode coupling in a photonic lantern

    DEFF Research Database (Denmark)

    Noordegraaf, Danny; Skovgaard, Peter M.; Nielsen, Martin D.

    2009-01-01

    We demonstrate the fabrication of a high performance multi-mode (MM) to single-mode (SM) splitter or “photonic lantern”, first described by Leon-Saval et al. (2005). Our photonic lantern is a solid all-glass version, and we show experimentally that this device can be used to achieve efficient...

  8. Multiparty Quantum English Auction Scheme Using Single Photons as Message Carrier

    Science.gov (United States)

    Liu, Ge; Zhang, Jian-Zhong; Xie, Shu-Cui

    2017-11-01

    In this paper, a secure and economic multiparty english auction protocol using the single photons as message carrier of bids is proposed. In order to achieve unconditional security, fairness, undeniability and so on, we adopt the decoy photon checking technique and quantum encryption algorithm. Analysis result shows that our protocol satisfies all the characteristics of traditional english auction, meanwhile, it can resist malicious attacks.

  9. Experimental realization of highly efficient broadband coupling of single quantum dots to a photonic crystal waveguide

    DEFF Research Database (Denmark)

    Lund-Hansen, Toke; Stobbe, Søren; Julsgaard, Brian

    2008-01-01

    We present time-resolved spontaneous emission measurements of single quantum dots embedded in photonic crystal waveguides. Quantum dots that couple to a photonic crystal waveguide are found to decay up to 27 times faster than uncoupled quantum dots. From these measurements -factors of up to 0...

  10. Boson Sampling with Single-Photon Fock States from a Bright Solid-State Source.

    Science.gov (United States)

    Loredo, J C; Broome, M A; Hilaire, P; Gazzano, O; Sagnes, I; Lemaitre, A; Almeida, M P; Senellart, P; White, A G

    2017-03-31

    A boson-sampling device is a quantum machine expected to perform tasks intractable for a classical computer, yet requiring minimal nonclassical resources as compared to full-scale quantum computers. Photonic implementations to date employed sources based on inefficient processes that only simulate heralded single-photon statistics when strongly reducing emission probabilities. Boson sampling with only single-photon input has thus never been realized. Here, we report on a boson-sampling device operated with a bright solid-state source of single-photon Fock states with high photon-number purity: the emission from an efficient and deterministic quantum dot-micropillar system is demultiplexed into three partially indistinguishable single photons, with a single-photon purity 1-g^{(2)}(0) of 0.990±0.001, interfering in a linear optics network. Our demultiplexed source is between 1 and 2 orders of magnitude more efficient than current heralded multiphoton sources based on spontaneous parametric down-conversion, allowing us to complete the boson-sampling experiment faster than previous equivalent implementations.

  11. Quantum State Transfer from a Single Photon to a Distant Quantum-Dot Electron Spin.

    Science.gov (United States)

    He, Yu; He, Yu-Ming; Wei, Yu-Jia; Jiang, Xiao; Chen, Kai; Lu, Chao-Yang; Pan, Jian-Wei; Schneider, Christian; Kamp, Martin; Höfling, Sven

    2017-08-11

    Quantum state transfer from flying photons to stationary matter qubits is an important element in the realization of quantum networks. Self-assembled semiconductor quantum dots provide a promising solid-state platform hosting both single photon and spin, with an inherent light-matter interface. Here, we develop a method to coherently and actively control the single-photon frequency bins in superposition using electro-optic modulators, and measure the spin-photon entanglement with a fidelity of 0.796±0.020. Further, by Greenberger-Horne-Zeilinger-type state projection on the frequency, path, and polarization degrees of freedom of a single photon, we demonstrate quantum state transfer from a single photon to a single electron spin confined in an InGaAs quantum dot, separated by 5 m. The quantum state mapping from the photon's polarization to the electron's spin is demonstrated along three different axes on the Bloch sphere, with an average fidelity of 78.5%.

  12. Quantum State Transfer from a Single Photon to a Distant Quantum-Dot Electron Spin

    Science.gov (United States)

    He, Yu; He, Yu-Ming; Wei, Yu-Jia; Jiang, Xiao; Chen, Kai; Lu, Chao-Yang; Pan, Jian-Wei; Schneider, Christian; Kamp, Martin; Höfling, Sven

    2017-08-01

    Quantum state transfer from flying photons to stationary matter qubits is an important element in the realization of quantum networks. Self-assembled semiconductor quantum dots provide a promising solid-state platform hosting both single photon and spin, with an inherent light-matter interface. Here, we develop a method to coherently and actively control the single-photon frequency bins in superposition using electro-optic modulators, and measure the spin-photon entanglement with a fidelity of 0.796 ±0.020 . Further, by Greenberger-Horne-Zeilinger-type state projection on the frequency, path, and polarization degrees of freedom of a single photon, we demonstrate quantum state transfer from a single photon to a single electron spin confined in an InGaAs quantum dot, separated by 5 m. The quantum state mapping from the photon's polarization to the electron's spin is demonstrated along three different axes on the Bloch sphere, with an average fidelity of 78.5%.

  13. Room temperature single photon source using fiber-integrated hexagonal boron nitride

    Science.gov (United States)

    Vogl, Tobias; Lu, Yuerui; Lam, Ping Koy

    2017-07-01

    Single photons are a key resource for quantum optics and optical quantum information processing. The integration of scalable room temperature quantum emitters into photonic circuits remains to be a technical challenge. Here we utilize a defect center in hexagonal boron nitride (hBN) attached by Van der Waals force onto a multimode fiber as a single photon source. We perform an optical characterization of the source in terms of spectrum, state lifetime, power saturation and photostability. A special feature of our source is that it allows for easy switching between fiber-coupled and free space single photon generation modes. In order to prove the quantum nature of the emission we measure the second-order correlation function {{g}(2)}≤ft(τ \\right) . For both fiber-coupled and free space emission, the {{g}(2)}≤ft(τ \\right) dips below 0.5 indicating operation in the single photon regime. The results so far demonstrate the feasibility of 2D material single photon sources for scalable photonic quantum information processing.

  14. NFAD Arrays for Single Photon Optical Communications at 1.5 um Project

    Data.gov (United States)

    National Aeronautics and Space Administration — For this program, we propose to develop large pixel-count single photon counting detector arrays suitable for deployment in spacecraft terminal receivers supporting...

  15. Central benzodiazepine receptor imaging and quantitation with single photon emission computerised tomography

    DEFF Research Database (Denmark)

    Okocha, C I; Kapczinski, F; Lassen, N

    1995-01-01

    This review discusses the current use of single photon emission computerised tomography (SPECT) for central benzodiazepine receptor imaging and quantitation. The general principles underlying SPECT imaging and receptor quantitation methods such as the kinetic, pseudo-equilibrium and steady...

  16. The influence of phonon bath on the control of single photon

    Science.gov (United States)

    Zhang, Wei; Lu, Hai-Tao

    2015-06-01

    The influence of vacuum fluctuation and phonon bath on the probability of single photon emission are both considered in the two-level system model theoretically; by using the master equations and generating function method we get the analytical expression of the second-order fluorescence correlation function, probability of single photon emission, and Mandel’s Q parameter. The results manifest that the coupling between the phonon bath and single photon source destroys the superposition state induced by the square laser pulse, the Rabi oscillation damped rapidly with the increasing of temperature. Theoretically, when the structure parameter of arsenide quantum dots α scaled to 0.1 times of the sample, the critical coherence-temperature will rise up to hundreds of Kelvin, which means a step forward to the realization of coherent control of single photon source at room temperature. Project supported by the Fundamental Research Funds for the Central Universities of Central South University, China (Grant No. 2014zzts145).

  17. Number-Resolved Single-Photon Detection with Ultralow Noise van der Waals Hybrid.

    Science.gov (United States)

    Roy, Kallol; Ahmed, Tanweer; Dubey, Harshit; Sai, T Phanindra; Kashid, Ranjit; Maliakal, Shruti; Hsieh, Kimberly; Shamim, Saquib; Ghosh, Arindam

    2018-01-01

    Van der Waals hybrids of graphene and transition metal dichalcogenides exhibit an extremely large response to optical excitation, yet counting of photons with single-photon resolution is not achieved. Here, a dual-gated bilayer graphene (BLG) and molybdenum disulphide (MoS 2 ) hybrid are demonstrated, where opening a band gap in the BLG allows extremely low channel (receiver) noise and large optical gain (≈10 10 ) simultaneously. The resulting device is capable of unambiguous determination of the Poissonian emission statistics of an optical source with single-photon resolution at an operating temperature of 80 K, dark count rate 0.07 Hz, and linear dynamic range of ≈40 dB. Single-shot number-resolved single-photon detection with van der Waals heterostructures may impact multiple technologies, including the linear optical quantum computation. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Single Photon Sensitive HgCdTe Avalanche Photodiode Detector (APD) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Leveraging Phase I SBIR successes, in Phase II, a single photon sensitive LIDAR receiver will be fabricated and delivered to NASA. In Phase I, high-gain,...

  19. Complementarity in single photon interference – the role of the mode function and vacuum fields

    National Research Council Canada - National Science Library

    Menzel, R; Puhlmann, D; Heuer, A

    2017-01-01

    ...).Single photon first order interferences of spatially separated regions from the cone structure of spontaneous parametric down conversion allow for analyzing the role of the mode function in quantum...

  20. Coherent state amplification using frequency conversion and a single photon source

    Science.gov (United States)

    Kasture, Sachin

    2017-11-01

    Quantum state discrimination lies at the heart of quantum communication and quantum cryptography protocols. Quantum Key Distribution (QKD) using coherent states and homodyne detection has been shown to be a feasible method for quantum communication over long distances. However, this method is still limited because of optical losses. Noiseless coherent state amplification has been proposed as a way to overcome this. Photon addition using stimulated Spontaneous Parametric Down-conversion followed by photon subtraction has been used as a way to implement amplification. However, this process occurs with very low probability which makes it very difficult to implement cascaded stages of amplification due to dark count probability in the single photon detectors used to herald the addition and subtraction of single photons. We discuss a scheme using the χ (2) and χ (3) optical non-linearity and frequency conversion (sum and difference frequency generation) along with a single photon source to implement photon addition. Unlike the photon addition scheme using SPDC, this scheme allows us to tune the success probability at the cost of reduced amplification. The photon statistics of the converted field can be controlled using the power of the pump field and the interaction time.

  1. Photonics

    CERN Document Server

    Andrews, David L

    2015-01-01

    Discusses the basic physical principles underlying thescience and technology of nanophotonics, its materials andstructures This volume presents nanophotonic structures and Materials.Nanophotonics is photonic science and technology that utilizeslight/matter interactions on the nanoscale where researchers arediscovering new phenomena and developing techniques that go wellbeyond what is possible with conventional photonics andelectronics.The topics discussed in this volume are: CavityPhotonics; Cold Atoms and Bose-Einstein Condensates; Displays;E-paper; Graphene; Integrated Photonics; Liquid Cry

  2. Photonics

    CERN Document Server

    Andrews, David L

    2015-01-01

    Discusses the basic physical principles underlying the technology instrumentation of photonics This volume discusses photonics technology and instrumentation. The topics discussed in this volume are: Communication Networks; Data Buffers; Defense and Security Applications; Detectors; Fiber Optics and Amplifiers; Green Photonics; Instrumentation and Metrology; Interferometers; Light-Harvesting Materials; Logic Devices; Optical Communications; Remote Sensing; Solar Energy; Solid-State Lighting; Wavelength Conversion Comprehensive and accessible coverage of the whole of modern photonics Emphas

  3. Photonics

    CERN Document Server

    Andrews, David L

    2015-01-01

    This book covers modern photonics accessibly and discusses the basic physical principles underlying all the applications and technology of photonicsThis volume covers the basic physical principles underlying the technology and all applications of photonics from statistical optics to quantum optics. The topics discussed in this volume are: Photons in perspective; Coherence and Statistical Optics; Complex Light and Singular Optics; Electrodynamics of Dielectric Media; Fast and slow Light; Holography; Multiphoton Processes; Optical Angular Momentum; Optical Forces, Trapping and Manipulation; Pol

  4. On-demand single-photon sources via quantum blockade and applications in decoy-state quantum key distribution.

    Science.gov (United States)

    Li, Ao; Chen, Tian; Zhou, Yiheng; Wang, Xiangbin

    2016-05-01

    Quantum blockades as a nonlinear quantum optical process have been well studied in recent years. Using the quantum trajectory method, we calculate and discuss the output photon number distributions of a single-photon blockade process in a Kerr nonlinear dissipative resonator, revealing that the probability of the single-photon state can be optimized. Then we show through numerical simulations that such a quasi-single-photon source can drastically raise the key rate in the decoy-state quantum key distribution.

  5. Time-dependent spectrum of a single photon and its positive-operator-valued measure

    Science.gov (United States)

    van Enk, S. J.

    2017-09-01

    Suppose we measure the time-dependent spectrum of a single photon. That is, we first send the photon through a set of frequency filters (which we assume to have different filter frequencies but the same finite bandwidth Γ ) and then record at what time (with some finite precision Δ t and some finite efficiency η ) and after passing what filter the photon is detected. What is the positive-operator-valued measure (POVM), the most general description of a quantum measurement, corresponding to such a measurement? We show how to construct the POVM in various cases, with special interest in the case Γ Δ t ≪1 (time-frequency uncertainty still holds, even in that limit). One application of the formalism is to heralding single photons. We also find a Hong-Ou-Mandel type of interference effect with two photons entering a frequency filter.

  6. A single molecule as a high-fidelity photon gun for producing intensity-squeezed light

    Science.gov (United States)

    Chu, Xiao-Liu; Götzinger, Stephan; Sandoghdar, Vahid

    2017-01-01

    A two-level atom cannot emit more than one photon at a time. As early as the 1980s, this quantum feature was identified as a gateway to 'single-photon sources', where a regular excitation sequence would create a stream of light particles with photon number fluctuations below the shot noise. Such an intensity-squeezed beam of light would be desirable for a range of applications, such as quantum imaging, sensing, enhanced precision measurements and information processing. However, experimental realizations of these sources have been hindered by large losses caused by low photon-collection efficiencies and photophysical shortcomings. By using a planar metallodielectric antenna applied to an organic molecule, we demonstrate the most regular stream of single photons reported to date. The measured intensity fluctuations were limited by our detection efficiency and amounted to 2.2 dB squeezing.

  7. Coherent perfect absorption in deeply subwavelength films in the single photon regime

    CERN Document Server

    Roger, Thomas; Bolduc, Eliot; Valente, Joao; Heitz, Julius J F; Jeffers, John; Soci, Cesare; Leach, Jonathan; Couteau, Christophe; Zheludev, Nikolay; Faccio, Daniele

    2016-01-01

    The technologies of heating, photovoltaics, water photocatalysis and artificial photosynthesis depend on the absorption of light and novel approaches such as coherent absorption from a standing wave promise total dissipation of energy. Extending the control of absorption down to very low light levels and eventually to the single photon regime is of great interest yet remains largely unexplored. Here we demonstrate the coherent absorption of single photons in a deeply sub-wavelength 50% absorber. We show that while absorption of photons from a travelling wave is probabilistic, standing wave absorption can be observed deterministically, with nearly unitary probability of coupling a photon into a mode of the material, e.g. a localised plasmon when this is a metamaterial excited at the plasmon resonance. These results bring a better understanding of the coherent absorption process, which is of central importance for light harvesting, detection, sensing and photonic data processing applications.

  8. Bright single photon source based on self-aligned quantum dot–cavity systems

    DEFF Research Database (Denmark)

    Maier, Sebastian; Gold, Peter; Forchel, Alfred

    2014-01-01

    We report on a quasi-planar quantum-dot-based single-photon source that shows an unprecedented high extraction efficiency of 42% without complex photonic resonator geometries or post-growth nanofabrication. This very high efficiency originates from the coupling of the photons emitted by a quantum...... dot to a Gaussian shaped nanohill defect that naturally arises during epitaxial growth in a self-aligned manner. We investigate the morphology of these defects and characterize the photonic operation mechanism. Our results show that these naturally arising coupled quantum dot-defects provide a new...... avenue for efficient (up to 42% demonstrated) and pure (g2(0) value of 0.023) single-photon emission....

  9. Optimal Entangling Operations between Deterministic Blocks of Qubits Encoded into Single Photons

    OpenAIRE

    Smith, Jake A.; Kaplan, Lev

    2017-01-01

    Here, we numerically simulate probabilistic elementary entangling operations between rail-encoded photons for the purpose of scalable universal quantum computation or communication. We propose grouping logical qubits into single-photon blocks wherein single-qubit rotations and the CNOT gate are fully deterministic and simple to implement. Inter-block communication is then allowed through said probabilistic entangling operations. We find a promising trend in the increasing probability of succe...

  10. All-silicon light-emitting diodes waveguide-integrated with superconducting single-photon detectors

    Science.gov (United States)

    Buckley, Sonia; Chiles, Jeffrey; McCaughan, Adam N.; Moody, Galan; Silverman, Kevin L.; Stevens, Martin J.; Mirin, Richard P.; Nam, Sae Woo; Shainline, Jeffrey M.

    2017-10-01

    We demonstrate cryogenic, electrically injected, waveguide-coupled Si light-emitting diodes (LEDs) operating at 1.22 μm. The active region of the LED consists of W centers implanted in the intrinsic region of a p-i-n diode. The LEDs are integrated on waveguides with superconducting nanowire single-photon detectors (SNSPDs). We demonstrate the scalability of this platform with an LED coupled to eleven SNSPDs in a single integrated photonic device.

  11. Highly anisotropic decay rate of single quantum dots in photonic crystal membranes

    DEFF Research Database (Denmark)

    Wang, Qin; Stobbe, Søren; Nielsen, Henri Thyrrestrup

    2010-01-01

    We measured the variation of spontaneous emission rates with polarization for self-assembled single quantum-dots in photonic crystal membranes, and obtained a maximum anisotropy factor of 6 between decay rates of the two nondegenerate bright states.......We measured the variation of spontaneous emission rates with polarization for self-assembled single quantum-dots in photonic crystal membranes, and obtained a maximum anisotropy factor of 6 between decay rates of the two nondegenerate bright states....

  12. Photonic transistor and router using a single quantum-dot-confined spin in a single-sided optical microcavity.

    Science.gov (United States)

    Hu, C Y

    2017-03-28

    The future Internet is very likely the mixture of all-optical Internet with low power consumption and quantum Internet with absolute security guaranteed by the laws of quantum mechanics. Photons would be used for processing, routing and com-munication of data, and photonic transistor using a weak light to control a strong light is the core component as an optical analogue to the electronic transistor that forms the basis of modern electronics. In sharp contrast to previous all-optical tran-sistors which are all based on optical nonlinearities, here I introduce a novel design for a high-gain and high-speed (up to terahertz) photonic transistor and its counterpart in the quantum limit, i.e., single-photon transistor based on a linear optical effect: giant Faraday rotation induced by a single electronic spin in a single-sided optical microcavity. A single-photon or classical optical pulse as the gate sets the spin state via projective measurement and controls the polarization of a strong light to open/block the photonic channel. Due to the duality as quantum gate for quantum information processing and transistor for optical information processing, this versatile spin-cavity quantum transistor provides a solid-state platform ideal for all-optical networks and quantum networks.

  13. Photonic transistor and router using a single quantum-dot-confined spin in a single-sided optical microcavity

    Science.gov (United States)

    Hu, C. Y.

    2017-03-01

    The future Internet is very likely the mixture of all-optical Internet with low power consumption and quantum Internet with absolute security guaranteed by the laws of quantum mechanics. Photons would be used for processing, routing and com-munication of data, and photonic transistor using a weak light to control a strong light is the core component as an optical analogue to the electronic transistor that forms the basis of modern electronics. In sharp contrast to previous all-optical tran-sistors which are all based on optical nonlinearities, here I introduce a novel design for a high-gain and high-speed (up to terahertz) photonic transistor and its counterpart in the quantum limit, i.e., single-photon transistor based on a linear optical effect: giant Faraday rotation induced by a single electronic spin in a single-sided optical microcavity. A single-photon or classical optical pulse as the gate sets the spin state via projective measurement and controls the polarization of a strong light to open/block the photonic channel. Due to the duality as quantum gate for quantum information processing and transistor for optical information processing, this versatile spin-cavity quantum transistor provides a solid-state platform ideal for all-optical networks and quantum networks.

  14. Single-photon single ionization of W$^{+}$ ions: experiment and theory

    CERN Document Server

    Müller, A; Hellhund, J; Holste, K; Kilcoyne, A L D; Phaneuf, R A; Ballance, C P; McLaughlin, B M

    2015-01-01

    Experimental and theoretical results are reported for photoionization of Ta-like (W$^{+}$) tungsten ions. Absolute cross sections were measured in the energy range 16 to 245 eV employing the photon-ion merged-beam setup at the Advanced Light Source in Berkeley. Detailed photon-energy scans at 100 meV bandwidth were performed in the 16 to 108 eV range. In addition, the cross section was scanned at 50 meV resolution in regions where fine resonance structures could be observed. Theoretical results were obtained from a Dirac-Coulomb R-matrix approach. Photoionization cross section calculations were performed for singly ionized atomic tungsten ions in their $5s^2 5p^6 5d^4({^5}D)6s \\; {^6}{\\rm D}_{J}$, $J$=1/2, ground level and the associated excited metastable levels with $J$=3/2, 5/2, 7/2 and 9/2. Since the ion beams used in the experiments must be expected to contain long-lived excited states also from excited configurations, additional cross-section calculations were performed for the second-lowest term, $5d^5...

  15. Interfacing Superconducting Qubits and Single Optical Photons Using Molecules in Waveguides

    Science.gov (United States)

    Das, Sumanta; Elfving, Vincent E.; Faez, Sanli; Sørensen, Anders S.

    2017-04-01

    We propose an efficient light-matter interface at optical frequencies between a single photon and a superconducting qubit. The desired interface is based on a hybrid architecture composed of an organic molecule embedded inside an optical waveguide and electrically coupled to a superconducting qubit placed near the outside surface of the waveguide. We show that high fidelity, photon-mediated, entanglement between distant superconducting qubits can be achieved with incident pulses at the single photon level. Such a low light level is highly desirable for achieving a coherent optical interface with superconducting qubit, since it minimizes decoherence arising from the absorption of light.

  16. Single photon superradiance and cooperative Lamb shift in an optoelectronic device

    CERN Document Server

    Frucci, Giulia; Vasanelli, Angela; Dailly, Baptiste; Todorov, Yanko; Sirtori, Carlo; Beaudoin, Grégoire; Sagnes, Isabelle

    2016-01-01

    Single photon superradiance is a strong enhancement of spontaneous emission appearing when a single excitation is shared between a large number of two-level systems. This enhanced rate can be accompanied by a shift of the emission frequency, the cooperative Lamb shift, issued from the exchange of virtual photons between the emitters. In this work we present a semiconductor optoelectronic device allowing the observation of these two phenomena at room temperature. We demonstrate experimentally and theoretically that plasma oscillations in spatially separated quantum wells interact through real and virtual photon exchange. This gives rise to a superradiant mode displaying a large cooperative Lamb shift.

  17. Investigating and improving student understanding of quantum mechanics in the context of single photon interference

    Directory of Open Access Journals (Sweden)

    Emily Marshman

    2017-04-01

    Full Text Available Single photon experiments involving a Mach-Zehnder interferometer can illustrate the fundamental principles of quantum mechanics, e.g., the wave-particle duality of a single photon, single photon interference, and the probabilistic nature of quantum measurement involving single photons. These experiments explicitly make the connection between the abstract quantum theory and concrete laboratory settings and have the potential to help students develop a solid grasp of the foundational issues in quantum mechanics. Here we describe students’ conceptual difficulties with these topics in the context of Mach-Zehnder interferometer experiments with single photons and how the difficulties found in written surveys and individual interviews were used as a guide in the development of a Quantum Interactive Learning Tutorial (QuILT. The QuILT uses an inquiry-based approach to learning and takes into account the conceptual difficulties found via research to help upper-level undergraduate and graduate students learn about foundational quantum mechanics concepts using the concrete quantum optics context. It strives to help students learn the basics of quantum mechanics in the context of single photon experiment, develop the ability to apply fundamental quantum principles to experimental situations in quantum optics, and explore the differences between classical and quantum ideas in a concrete context. We discuss the findings from in-class evaluations suggesting that the QuILT was effective in helping students learn these abstract concepts.

  18. Investigating and improving student understanding of quantum mechanics in the context of single photon interference

    Science.gov (United States)

    Marshman, Emily; Singh, Chandralekha

    2017-06-01

    Single photon experiments involving a Mach-Zehnder interferometer can illustrate the fundamental principles of quantum mechanics, e.g., the wave-particle duality of a single photon, single photon interference, and the probabilistic nature of quantum measurement involving single photons. These experiments explicitly make the connection between the abstract quantum theory and concrete laboratory settings and have the potential to help students develop a solid grasp of the foundational issues in quantum mechanics. Here we describe students' conceptual difficulties with these topics in the context of Mach-Zehnder interferometer experiments with single photons and how the difficulties found in written surveys and individual interviews were used as a guide in the development of a Quantum Interactive Learning Tutorial (QuILT). The QuILT uses an inquiry-based approach to learning and takes into account the conceptual difficulties found via research to help upper-level undergraduate and graduate students learn about foundational quantum mechanics concepts using the concrete quantum optics context. It strives to help students learn the basics of quantum mechanics in the context of single photon experiment, develop the ability to apply fundamental quantum principles to experimental situations in quantum optics, and explore the differences between classical and quantum ideas in a concrete context. We discuss the findings from in-class evaluations suggesting that the QuILT was effective in helping students learn these abstract concepts.

  19. Weak measurement of the arrival times of single photons and pairs of entangled photons

    Science.gov (United States)

    Ahnert, S. E.; Payne, M. C.

    2004-04-01

    In this paper we propose a setup for the weak measurement of photon arrival time. It is found that the weak values of this arrival time can lie far away from the expectation value, and in principle also in regions forbidden by special relativity. We discuss in brief the implications of these results as well as their reconciliation with the principle of causality. Furthermore, an analysis of the weak arrival times of a pair of photons in a Bell state shows that these weak arrival times are correlated.

  20. An integrated single photon detector array using porous anodic alumina

    NARCIS (Netherlands)

    Melai, J.; Salm, Cora; Schmitz, Jurriaan; Smits, Sander M.; Visschers, J.L.

    2006-01-01

    The aim of the work is fabrication of a photon detector array made using IC compatible wafer-scale post-processing stepts. Plans will be presented to outline these fabrication steps. The detector comprises an integrated Micro-Channel-Plate and an imaging chip like Medipix2. The aim of the work is

  1. Continuously scanning time-correlated single-photon-counting single-pixel 3-D lidar

    Science.gov (United States)

    Henriksson, Markus; Larsson, Håkan; Grönwall, Christina; Tolt, Gustav

    2017-03-01

    Time-correlated single-photon-counting (TCSPC) lidar provides very high resolution range measurements. This makes the technology interesting for three-dimensional imaging of complex scenes with targets behind foliage or other obscurations. TCSPC is a statistical method that demands integration of multiple measurements toward the same area to resolve objects at different distances within the instantaneous field-of-view. Point-by-point scanning will demand significant overhead for the movement, increasing the measurement time. Here, the effect of continuously scanning the scene row-by-row is investigated and signal processing methods to transform this into low-noise point clouds are described. The methods are illustrated using measurements of a characterization target and an oak and hazel copse. Steps between different surfaces of less than 5 cm in range are resolved as two surfaces.

  2. arXiv Single-electron and single-photon sensitivity with a silicon Skipper CCD

    CERN Document Server

    Tiffenberg, Javier; Drlica-Wagner, Alex; Essig, Rouven; Guardincerri, Yann; Holland, Steve; Volansky, Tomer; Yu, Tien-Tien

    2017-09-26

    We have developed ultralow-noise electronics in combination with repetitive, nondestructive readout of a thick, fully depleted charge-coupled device (CCD) to achieve an unprecedented noise level of 0.068  e- rms/pixel. This is the first time that discrete subelectron readout noise has been achieved reproducible over millions of pixels on a stable, large-area detector. This enables the contemporaneous, discrete, and quantized measurement of charge in pixels, irrespective of whether they contain zero electrons or thousands of electrons. Thus, the resulting CCD detector is an ultra-sensitive calorimeter. It is also capable of counting single photons in the optical and near-infrared regime. Implementing this innovative non-destructive readout system has a negligible impact on CCD design and fabrication, and there are nearly immediate scientific applications. As a particle detector, this CCD will have unprecedented sensitivity to low-mass dark matter particles and coherent neutrino-nucleus scattering, while ...

  3. Single-photon emission at 1.5 μm from an InAs/InP quantum dot with highly suppressed multi-photon emission probabilities

    Science.gov (United States)

    Miyazawa, T.; Takemoto, K.; Nambu, Y.; Miki, S.; Yamashita, T.; Terai, H.; Fujiwara, M.; Sasaki, M.; Sakuma, Y.; Takatsu, M.; Yamamoto, T.; Arakawa, Y.

    2016-09-01

    We have demonstrated highly pure single-photon emissions from an InAs/InP quantum dot at the wavelength of 1.5 μm. By applying quasi-resonant excitation, one exciton is deterministically generated in an excited state, which then relaxes to the exciton ground state before recombining to emit a single photon. The photon-correlation function of the emission from the exciton ground state exhibits a record g(2)(0) value of (4.4 ± 0.2) × 10-4 measured using high-performance super-conducting single-photon detectors, without any background subtraction. This single-photon source with extremely low multi-photon emission probability paves the way to realize long distance quantum key distribution and low error-rate quantum computation.

  4. Very Efficient Single-Photon Sources Based on Quantum Dots in Photonic Wires

    DEFF Research Database (Denmark)

    Gerard, Jean-Michel; Claudon, Julien; Bleuse, Joel

    2014-01-01

    . By placing a tip-shaped or trumpet-like tapering at the output end of the wire, a highly directional Gaussian far-field emission pattern is obtained. More generally, a photonic wire containing a quantum dot appears as an attractive template to explore and exploit in a solid-state system the unique optical...

  5. A highly efficient single-photon source based on a quantum dot in a photonic nanowire

    DEFF Research Database (Denmark)

    Claudon, Julien; Bleuse, Joel; Malik, Nitin Singh

    2010-01-01

    –4 or a semiconductor quantum dot5–7. Achieving a high extraction efficiency has long been recognized as a major issue, and both classical solutions8 and cavity quantum electrodynamics effects have been applied1,9–12. We adopt a different approach, based on an InAs quantum dot embedded in a GaAs photonic nanowire...

  6. Multi-state discrimination below the quantum noise limit at the single-photon level

    Science.gov (United States)

    Ferdinand, A. R.; DiMario, M. T.; Becerra, F. E.

    2017-10-01

    Measurements approaching the ultimate quantum limits of sensitivity are central in quantum information processing, quantum metrology, and communication. Quantum measurements to discriminate multiple states at the single-photon level are essential for optimizing information transfer in low-power optical communications and quantum communications, and can enhance the capabilities of many quantum information protocols. Here, we theoretically investigate and experimentally demonstrate the discrimination of multiple coherent states of light with sensitivities surpassing the quantum noise limit (QNL) at the single-photon level under realistic conditions of loss and noise based on strategies implementing globally-optimized adaptive measurements with single photon counting and displacement operations. These discrimination strategies can provide realistic advantages to enhance information transfer at low powers, and are compatible with photon number resolving detection, which provides robustness at high powers, thus allowing for surpassing the QNL at arbitrary input power levels under realistic conditions.

  7. Observation of entanglement between a quantum dot spin and a single photon.

    Science.gov (United States)

    Gao, W B; Fallahi, P; Togan, E; Miguel-Sanchez, J; Imamoglu, A

    2012-11-15

    Entanglement has a central role in fundamental tests of quantum mechanics as well as in the burgeoning field of quantum information processing. Particularly in the context of quantum networks and communication, a main challenge is the efficient generation of entanglement between stationary (spin) and propagating (photon) quantum bits. Here we report the observation of quantum entanglement between a semiconductor quantum dot spin and the colour of a propagating optical photon. The demonstration of entanglement relies on the use of fast, single-photon detection, which allows us to project the photon into a superposition of red and blue frequency components. Our results extend the previous demonstrations of single-spin/single-photon entanglement in trapped ions, neutral atoms and nitrogen-vacancy centres to the domain of artificial atoms in semiconductor nanostructures that allow for on-chip integration of electronic and photonic elements. As a result of its fast optical transitions and favourable selection rules, the scheme we implement could in principle generate nearly deterministic entangled spin-photon pairs at a rate determined ultimately by the high spontaneous emission rate. Our observation constitutes a first step towards implementation of a quantum network with nodes consisting of semiconductor spin quantum bits.

  8. Single-Photon-Sensitive HgCdTe Avalanche Photodiode Detector

    Science.gov (United States)

    Huntington, Andrew

    2013-01-01

    The purpose of this program was to develop single-photon-sensitive short-wavelength infrared (SWIR) and mid-wavelength infrared (MWIR) avalanche photodiode (APD) receivers based on linear-mode HgCdTe APDs, for application by NASA in light detection and ranging (lidar) sensors. Linear-mode photon-counting APDs are desired for lidar because they have a shorter pixel dead time than Geiger APDs, and can detect sequential pulse returns from multiple objects that are closely spaced in range. Linear-mode APDs can also measure photon number, which Geiger APDs cannot, adding an extra dimension to lidar scene data for multi-photon returns. High-gain APDs with low multiplication noise are required for efficient linear-mode detection of single photons because of APD gain statistics -- a low-excess-noise APD will generate detectible current pulses from single photon input at a much higher rate of occurrence than will a noisy APD operated at the same average gain. MWIR and LWIR electron-avalanche HgCdTe APDs have been shown to operate in linear mode at high average avalanche gain (M > 1000) without excess multiplication noise (F = 1), and are therefore very good candidates for linear-mode photon counting. However, detectors fashioned from these narrow-bandgap alloys require aggressive cooling to control thermal dark current. Wider-bandgap SWIR HgCdTe APDs were investigated in this program as a strategy to reduce detector cooling requirements.

  9. Efficient frequency downconversion at the single photon level from the red spectral range to the telecommunications C-band.

    Science.gov (United States)

    Zaske, Sebastian; Lenhard, Andreas; Becher, Christoph

    2011-06-20

    We report on single photon frequency downconversion from the red part of the spectrum (738 nm) to the telecommunications C-band. By mixing attenuated laser pulses with an average photon number per pulse telecommunications wavelengths.

  10. Two-photon interference using background-free quantum frequency conversion of single photons emitted by an InAs quantum dot.

    Science.gov (United States)

    Ates, Serkan; Agha, Imad; Gulinatti, Angelo; Rech, Ivan; Rakher, Matthew T; Badolato, Antonio; Srinivasan, Kartik

    2012-10-05

    We show that quantum frequency conversion (QFC) can overcome the spectral distinguishability common to inhomogeneously broadened solid-state quantum emitters. QFC is implemented by combining single photons from an InAs/GaAs quantum dot (QD) at 980 nm with a 1550 nm pump laser in a periodically poled lithium niobate (PPLN) waveguide to generate photons at 600 nm with a signal-to-background ratio exceeding 100:1. Photon correlation and two-photon interference measurements confirm that both the single photon character and wave packet interference of individual QD states are preserved during frequency conversion. Finally, we convert two spectrally separate QD transitions to the same wavelength in a single PPLN waveguide and show that the resulting field exhibits nonclassical two-photon interference.

  11. Hybrid microfiber-lithium-niobate nanowaveguide structures as high-purity heralded single-photon sources

    Science.gov (United States)

    Main, Philip; Mosley, Peter J.; Ding, Wei; Zhang, Lijian; Gorbach, Andrey V.

    2016-12-01

    We propose a compact, fiber-integrated architecture for photon-pair generation by parametric downconversion with unprecedented flexibility in the properties of the photons produced. Our approach is based on a thin-film lithium niobate nanowaveguide, evanescently coupled to a tapered silica microfiber. We demonstrate how controllable mode hybridization between the fiber and waveguide yields control over the joint spectrum of the photon pairs. We also investigate how independent engineering of the linear and nonlinear properties of the structure can be achieved through the addition of a tapered, proton-exchanged layer to the waveguide. This allows further refinement of the joint spectrum through custom profiling of the effective nonlinearity, drastically improving the purity of the heralded photons. We give details of a source design capable of generating heralded single photons in the telecom wavelength range with purity of at least 0.95, and we provide a feasible fabrication methodology.

  12. Coherent properties of single quantum dot transitions and single photon emission

    Energy Technology Data Exchange (ETDEWEB)

    Ester, Patrick

    2008-04-23

    of the first laser pulse. The relative phase of the QDs exciton can be controlled externally via the bias voltage. This effect is the basis for the observation of RAMSEY-fringes, which are presented in this work. The coherent manipulation of the p-shell is the basis for a novel excitation scheme for single photon emission. In this work it is shown that the first excited state can be coherently manipulated, similar to the ground state. (orig.)

  13. A novel ultra-broadband single polarization single mode photonic crystal fiber

    Science.gov (United States)

    Jiang, Linghong; Zheng, Yi; Hou, Lantian; Zheng, Kai; Peng, Jiying; Zhao, Xingtao

    2017-08-01

    The concept of employing a central hole infiltrated with nematic liquid crystal (NLC) and two additional air holes in the core region is exploited to obtain an ultra-broadband single polarization single mode photonic crystal fiber (SPSM-PCF). The effects of structural parameters on the SPSM operation are studied using the full-vectorial finite element method. Numerical results show that the proposed structure can attain the SPSM operation bandwidth of 1610 nm (from 1.51 to 3.12 μm) with confinement loss lower than 0.01 dB/km. The SPSM operation range can also be widely tuned to shorter wavelengths by adjusting the structure parameters. And meanwhile, a broad dispersion-flattened SPSM PCF is also obtained around the communication wavelength. Moreover, the dual-core SPSM PCF has also been investigated, enabling potential applications in the wavelength splitter of 1.31 and 1.55 μm bands at a short fiber length of 1.629 mm with SPSM operation.

  14. Development of a high-speed single-photon pixellated detector for visible wavelengths

    Energy Technology Data Exchange (ETDEWEB)

    Raighne, Aaron Mac [Department of Physics and Astronomy, University of Glasgow, England (United Kingdom)], E-mail: aaron.macraighne@gmail.com; Teixeira, Antonio; Mathot, Serge [CERN, Geneve (Switzerland); McPhate, Jason; Vallerga, John [University of California, Berkeley (United States); Jarron, Pierre [CERN, Geneve (Switzerland); Brownlee, Colin [Marine Biological Association of the United Kingdom, Plymouth (United Kingdom); O' Shea, Val [Department of Physics and Astronomy, University of Glasgow, England (United Kingdom)

    2009-08-01

    We present the development of a high-speed, single-photon counting, Hybrid Photo Detector (HPD). The HPD consists of a vacuum tube, containing the detector assembly, sealed with a transparent optical input window. Photons incident on the photocathode eject a photoelectron into a large electric field, which accelerates the incident electron onto a silicon detector. The silicon detector is bump bonded to a Medipix readout chip. This set-up allows for the detection and readout of low incident photon intensities at rates that are otherwise unattainable with current camera technology. Reported is the fabrication of the camera that brings together a range of sophisticated design and fabrication techniques and the expected theoretical imaging performance. Applications to cellular and molecular microscopy are also described in which single-photon-counting abilities at high frame rates are crucial.

  15. Memory effect in silicon time-gated single-photon avalanche diodes

    Energy Technology Data Exchange (ETDEWEB)

    Dalla Mora, A.; Contini, D., E-mail: davide.contini@polimi.it; Di Sieno, L. [Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy); Tosi, A.; Boso, G.; Villa, F. [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy); Pifferi, A. [Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy); CNR, Istituto di Fotonica e Nanotecnologie, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy)

    2015-03-21

    We present a comprehensive characterization of the memory effect arising in thin-junction silicon Single-Photon Avalanche Diodes (SPADs) when exposed to strong illumination. This partially unknown afterpulsing-like noise represents the main limiting factor when time-gated acquisitions are exploited to increase the measurement dynamic range of very fast (picosecond scale) and faint (single-photon) optical signals following a strong stray one. We report the dependences of this unwelcome signal-related noise on photon wavelength, detector temperature, and biasing conditions. Our results suggest that this so-called “memory effect” is generated in the deep regions of the detector, well below the depleted region, and its contribution on detector response is visible only when time-gated SPADs are exploited to reject a strong burst of photons.

  16. Efficient multi-mode to single-mode conversion in a 61 port photonic lantern

    DEFF Research Database (Denmark)

    Noordegraaf, Danny; Skovgaard, Peter M. W.; Dybendahl Maack, Martin

    2010-01-01

    We demonstrate the fabrication of a multi-mode (MM) to 61 port single-mode (SM) splitter or "Photonic Lantern". Low port count Photonic Lanterns were first described by Leon-Saval et al. (2005). These are based on a photonic crystal fiber type design, with air-holes defining the multi-mode fiber...... (MMF) cladding. Our fabricated Photonic Lanterns are solid all-glass versions, with the MMF defined by a low-index tube surrounding the single-mode fibers (SMFs). We show experimentally that these devices can be used to achieve efficient and reversible coupling between a MMF and 61 SMFs, when perfectly...... of astrophotonics for coupling MM star-light to an ensemble of SM fibers in order to perform fiber Bragg grating based spectral filtering....

  17. Development of a high-speed single-photon pixellated detector for visible wavelengths

    CERN Document Server

    Mac Raighne, Aaron; Mathot, Serge; McPhate, Jason; Vallerga, John; Jarron, Pierre; Brownlee, Colin; O’Shea, Val

    2009-01-01

    We present the development of a high-speed, single-photon counting, Hybrid Photo Detector (HPD). The HPD consists of a vacuum tube, containing the detector assembly, sealed with a transparent optical input window. Photons incident on the photocathode eject a photoelectron into a large electric field, which accelerates the incident electron onto a silicon detector. The silicon detector is bump bonded to a Medipix readout chip. This set-up allows for the detection and readout of low incident photon intensities at rates that are otherwise unattainable with current camera technology. Reported is the fabrication of the camera that brings together a range of sophisticated design and fabrication techniques and the expected theoretical imaging performance. Applications to cellular and molecular microscopy are also described in which single-photon-counting abilities at high frame rates are crucial

  18. Single photon emission from site-controlled InGaN/GaN quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Lei; Hill, Tyler A.; Deng, Hui, E-mail: dengh@umich.edu [Department of Physics, University of Michigan, 450 Church Street, Ann Arbor, Michigan 48109 (United States); Teng, Chu-Hsiang; Lee, Leung-Kway; Ku, Pei-Cheng, E-mail: peicheng@umich.edu [Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Ave., Ann Arbor, Michigan 48109 (United States)

    2013-11-04

    Single photon emission was observed from site-controlled InGaN/GaN quantum dots. The single-photon nature of the emission was verified by the second-order correlation function up to 90 K, the highest temperature to date for site-controlled quantum dots. Micro-photoluminescence study on individual quantum dots showed linearly polarized single exciton emission with a lifetime of a few nanoseconds. The dimensions of these quantum dots were well controlled to the precision of state-of-the-art fabrication technologies, as reflected in the uniformity of their optical properties. The yield of optically active quantum dots was greater than 90%, among which 13%–25% exhibited single photon emission at 10 K.

  19. New cardiac cameras: single-photon emission CT and PET.

    Science.gov (United States)

    Slomka, Piotr J; Berman, Daniel S; Germano, Guido

    2014-07-01

    Nuclear cardiology instrumentation has evolved significantly in the recent years. Concerns about radiation dose and long acquisition times have propelled developments of dedicated high-efficiency cardiac SPECT scanners. Novel collimator designs, such as multipinhole or locally focusing collimators arranged in geometries that are optimized for cardiac imaging, have been implemented to enhance photon-detection sensitivity. Some of these new SPECT scanners use solid-state photon detectors instead of photomultipliers to improve image quality and to reduce the scanner footprint. These new SPECT devices allow dramatic up to 7-fold reduction in acquisition times or similar reduction in radiation dose. In addition, new hardware for photon attenuation correction allowing ultralow radiation doses has been offered by some vendors. To mitigate photon attenuation artifacts for the new SPECT scanners not equipped with attenuation correction hardware, 2-position (upright-supine or prone-supine) imaging has been proposed. PET hardware developments have been primarily driven by the requirements of oncologic imaging, but cardiac imaging can benefit from improved PET image quality and improved sensitivity of 3D systems. The time-of-flight reconstruction combined with resolution recovery techniques is now implemented by all major PET vendors. These new methods improve image contrast and image resolution and reduce image noise. High-sensitivity 3D PET without interplane septa allows reduced radiation dose for cardiac perfusion imaging. Simultaneous PET/MR hybrid system has been developed. Solid-state PET detectors with avalanche photodiodes or digital silicon photomultipliers have been introduced, and they offer improved imaging characteristics and reduced sensitivity to electromagnetic MR fields. Higher maximum count rate of the new PET detectors allows routine first-pass Rb-82 imaging, with 3D PET acquisition enabling clinical utilization of dynamic imaging with myocardial flow

  20. Third-order antibunching from an imperfect single-photon source.

    Science.gov (United States)

    Stevens, Martin J; Glancy, Scott; Nam, Sae Woo; Mirin, Richard P

    2014-02-10

    We measure second- and third-order temporal coherences, g((2))(τ) and g((3))(τ1,τ2), of an optically excited single-photon source: an InGaAs quantum dot in a microcavity pedestal. Increasing the optical excitation power leads to an increase in the measured count rate, and also an increase in multi-photon emission probability. We show that standard measurements of g((2)) provide limited information about this multi-photon probability, and that more information can be gained by simultaneously measuring g((3)). Experimental results are compared with a simple theoretical model to show that the observed antibunchings are consistent with an incoherent addition of two sources: 1) an ideal single-photon source that never emits multiple photons and 2) a background cavity emission having Poissonian photon number statistics. Spectrally resolved cross-correlation measurements between quantum-dot and cavity modes show that photons from these two sources are largely uncorrelated, further supporting the model. We also analyze the Hanbury Brown-Twiss interferometer implemented with two or three "click" detectors, and explore the conditions under which it can be used to accurately measure g((2))(τ) and g((3))(τ1,τ2).

  1. Quantum interference induced photon blockade in a coupled single quantum dot-cavity system.

    Science.gov (United States)

    Tang, Jing; Geng, Weidong; Xu, Xiulai

    2015-03-18

    We propose an experimental scheme to implement a strong photon blockade with a single quantum dot coupled to a nanocavity. The photon blockade effect can be tremendously enhanced by driving the cavity and the quantum dot simultaneously with two classical laser fields. This enhancement of photon blockade is ascribed to the quantum interference effect to avoid two-photon excitation of the cavity field. Comparing with Jaynes-Cummings model, the second-order correlation function at zero time delay g((2))(0) in our scheme can be reduced by two orders of magnitude and the system sustains a large intracavity photon number. A red (blue) cavity-light detuning asymmetry for photon quantum statistics with bunching or antibunching characteristics is also observed. The photon blockade effect has a controllable flexibility by tuning the relative phase between the two pumping laser fields and the Rabi coupling strength between the quantum dot and the pumping field. Moreover, the photon blockade scheme based on quantum interference mechanism does not require a strong coupling strength between the cavity and the quantum dot, even with the pure dephasing of the system. This simple proposal provides an effective way for potential applications in solid state quantum computation and quantum information processing.

  2. Quantum non-demolition detection of single microwave photons in a circuit

    Science.gov (United States)

    Johnson, B. R.; Reed, M. D.; Houck, A. A.; Schuster, D. I.; Bishop, Lev S.; Ginossar, E.; Gambetta, J. M.; Dicarlo, L.; Frunzio, L.; Girvin, S. M.; Schoelkopf, R. J.

    2010-09-01

    Thorough control of quantum measurement is key to the development of quantum information technologies. Many measurements are destructive, removing more information from the system than they obtain. Quantum non-demolition (QND) measurements allow repeated measurements that give the same eigenvalue. They could be used for several quantum information processing tasks such as error correction, preparation by measurement and one-way quantum computing. Achieving QND measurements of photons is especially challenging because the detector must be completely transparent to the photons while still acquiring information about them. Recent progress in manipulating microwave photons in superconducting circuits has increased demand for a QND detector that operates in the gigahertz frequency range. Here we demonstrate a QND detection scheme that measures the number of photons inside a high-quality-factor microwave cavity on a chip. This scheme maps a photon number, n, onto a qubit state in a single-shot by means of qubit-photon logic gates. We verify the operation of the device for n=0 and 1 by analysing the average correlations of repeated measurements, and show that it is 90% QND. It differs from previously reported detectors because its sensitivity is strongly selective to chosen photon number states. This scheme could be used to monitor the state of a photon-based memory in a quantum computer.

  3. Indistinguishable and efficient single photons from a quantum dot in a planar nanobeam waveguide

    DEFF Research Database (Denmark)

    Kirsanské, Gabija; Nielsen, Henri Thyrrestrup; Daveau, Raphaël Sura

    2017-01-01

    We demonstrate a high-purity source of indistinguishable single photons using a quantum dot embedded in a nanophotonic waveguide. The source features a near-unity internal coupling efficiency and the collected photons are efficiently coupled off chip by implementing a taper that adiabatically...... allows pinpointing the residual decoherence processes, notably the effect of phonon broadening. Strict resonant excitation is implemented as well as another means of suppressing photon jitter, and the additional complexity of suppressing the excitation laser source is addressed. The paper opens a clear...

  4. Atom-Resonant Heralded Single Photons by Interaction-Free Measurement

    OpenAIRE

    Wolfgramm, Florian; Astiz, Yannick A. de Icaza; Beduini, Federica A.; Cere, Alessandro; Mitchell, Morgan W.

    2011-01-01

    We demonstrate the generation of rubidium-resonant heralded single photons for quantum memories. Photon pairs are created by cavity-enhanced down-conversion and narrowed in bandwidth to 7 MHz with a novel atom-based filter operating by "interaction-free measurement" principles. At least 94% of the heralded photons are atom-resonant as demonstrated by a direct absorption measurement with rubidium vapor. A heralded auto-correlation measurement shows $g_c^{(2)}(0)=0.040 \\pm 0.012$, i.e., suppres...

  5. Channel analysis for single photon underwater free space quantum key distribution.

    Science.gov (United States)

    Shi, Peng; Zhao, Shi-Cheng; Gu, Yong-Jian; Li, Wen-Dong

    2015-03-01

    We investigate the optical absorption and scattering properties of underwater media pertinent to our underwater free space quantum key distribution (QKD) channel model. With the vector radiative transfer theory and Monte Carlo method, we obtain the attenuation of photons, the fidelity of the scattered photons, the quantum bit error rate, and the sifted key generation rate of underwater quantum communication. It can be observed from our simulations that the most secure single photon underwater free space QKD is feasible in the clearest ocean water.

  6. Mapping the Local Density of Optical States of a Photonic Crystal with Single Quantum Dots

    DEFF Research Database (Denmark)

    Wang, Qin; Stobbe, Søren; Lodahl, Peter

    2011-01-01

    We use single self-assembled InGaAs quantum dots as internal probes to map the local density of optical states of photonic crystal membranes. The employed technique separates contributions from nonradiative recombination and spin-flip processes by properly accounting for the role of the exciton...... fine structure. We observe inhibition factors as high as 70 and compare our results to local density of optical states calculations available from the literature, thereby establishing a quantitative understanding of photon emission in photonic crystal membranes. © 2011 American Physical Society....

  7. Refractive elements for the measurement of the orbital angular momentum of a single photon.

    Science.gov (United States)

    Lavery, Martin P J; Robertson, David J; Berkhout, Gregorius C G; Love, Gordon D; Padgett, Miles J; Courtial, Johannes

    2012-01-30

    We have developed a mode transformer comprising two custom refractive optical elements which convert orbital angular momentum states into transverse momentum states. This transformation allows for an efficient measurement of the orbital angular momentum content of an input light beam. We characterise the channel capacity of the system for 50 input modes, giving a maximum value of 3.46 bits per photon. Using an electron multiplying CCD (EMCCD) camera with a laser source attenuated such that on average there is less than one photon present within the system per measurement period, we demonstrate that the elements are efficient for the use in single photon experiments.

  8. Millijoule Pulse Energy Second Harmonic Generation With Single-Stage Photonic Bandgap Rod Fiber Laser

    DEFF Research Database (Denmark)

    Laurila, Marko; Saby, Julien; Alkeskjold, Thomas Tanggaard

    2011-01-01

    In this paper, we demonstrate, for the first time, a single-stage Q-switched single-mode (SM) ytterbium-doped rod fiber laser delivering record breaking pulse energies at visible and UV light. We use a photonic bandgap rod fiber with a mode field diameter of 59μm based on a new distributed...

  9. Modes of an endlessly single-mode photonic crystal fiber: a finite element investigation

    NARCIS (Netherlands)

    Uranus, H.P.; Hoekstra, Hugo; van Groesen, Embrecht W.C.

    2004-01-01

    Using a finite-element mode solver, the modes of a commercial endlessly single-mode photonic crystal fiber (ESM-PCF) were investigated. Based on the loss discrimination between the dominant and the nearest higher order mode, we set-up a criterion for the single-modeness. Using that measure, we

  10. On-chip detection of non-classical light by scalable integration of single-photon detectors.

    Science.gov (United States)

    Najafi, Faraz; Mower, Jacob; Harris, Nicholas C; Bellei, Francesco; Dane, Andrew; Lee, Catherine; Hu, Xiaolong; Kharel, Prashanta; Marsili, Francesco; Assefa, Solomon; Berggren, Karl K; Englund, Dirk

    2015-01-09

    Photonic-integrated circuits have emerged as a scalable platform for complex quantum systems. A central goal is to integrate single-photon detectors to reduce optical losses, latency and wiring complexity associated with off-chip detectors. Superconducting nanowire single-photon detectors (SNSPDs) are particularly attractive because of high detection efficiency, sub-50-ps jitter and nanosecond-scale reset time. However, while single detectors have been incorporated into individual waveguides, the system detection efficiency of multiple SNSPDs in one photonic circuit-required for scalable quantum photonic circuits-has been limited to classical light.

  11. Multianode photomultipliers as position-sensitive detectors of single photons

    CERN Document Server

    Korpar, S; Pestotnik, R; Gorisek, A; Stanovnik, A; Staric, M; Skrk, D

    2000-01-01

    Tests of 2300 Hamamatsu multianode photomultipliers (1543 pieces of R5900-M16 and 762 pieces of R5900-M4) have been tested on the bench in order to evaluate their performance for use as position-sensitive photon detectors in the ring imaging Cherenkov counter of the HERA-B experiment. A weak and stable source of photons has been obtained by Cherenkov radiation of electrons from a sup 9 sup 0 Sr source in a quartz radiator. From measurements of the count rate versus high voltage, optimal high-voltage values have been obtained as well as a parameter (RQE) corresponding to the relative quantum efficiency. Distributions of the number of photomultipliers as a function of the optimal high voltage and as a function of the relative quantum efficiency are presented. The measured parameters are in good correlation with those provided by the manufacturer. The stability of the photomultipliers has also been followed over two years. The observed count rate decrease is consistent with the radioactive decay of sup 9 sup 0 S...

  12. Single photon avalanche detectors: prospects of new quenching and gain mechanisms

    Directory of Open Access Journals (Sweden)

    Hall David

    2015-11-01

    Full Text Available While silicon single-photon avalanche diodes (SPAD have reached very high detection efficiency and timing resolution, their use in fibre-optic communications, optical free space communications, and infrared sensing and imaging remains limited. III-V compounds including InGaAs and InP are the prevalent materials for 1550 nm light detection. However, even the most sensitive 1550 nm photoreceivers in optical communication have a sensitivity limit of a few hundred photons. Today, the only viable approach to achieve single-photon sensitivity at 1550 nm wavelength from semiconductor devices is to operate the avalanche detectors in Geiger mode, essentially trading dynamic range and speed for sensitivity. As material properties limit the performance of Ge and III-V detectors, new conceptual insight with regard to novel quenching and gain mechanisms could potentially address the performance limitations of III-V SPADs. Novel designs that utilise internal self-quenching and negative feedback can be used to harness the sensitivity of single-photon detectors,while drastically reducing the device complexity and increasing the level of integration. Incorporation of multiple gain mechanisms, together with self-quenching and built-in negative feedback, into a single device also hold promise for a new type of detector with single-photon sensitivity and large dynamic range.

  13. Unconditionally secure key distillation from multi-photons in a single-photon polarization based quantum key distribution

    CERN Document Server

    Tamaki, K

    2005-01-01

    In this presentation, we show some counter-examples to a naive belief that the security of QKD is based on no-cloning theorem. One example is shown by explicitly proving that one can indeed generate an unconditionally secure key from Alice's two-photon emission part in "SARG04 protocol" proposed by V. Scarani et al, in Phys. Rev. Lett. 92, 057901 (2004). This protocol differs from BB84 only in the classical communication. It is, thus, interesting to see how only the classical communication of QKD protocol might qualitatively change its security. We also show that one can generate an unconditionally secure key from the single to the four-photon part in a generalized SARG04 that uses six states. Finally, we also compare the bit error rate threshold of these protocols with the one in BB84 and the original six-state protocol assuming a depolarizing channel.

  14. High-speed bridge circuit for InGaAs avalanche photodiode single-photon detector

    Science.gov (United States)

    Hashimoto, Hirofumi; Tomita, Akihisa; Okamoto, Atsushi

    2014-02-01

    Because of low power consumption and small footprint, avalanche photodiodes (APD) have been commonly applied to photon detection. Recently, high speed quantum communication has been demonstrated for high bit-rate quantum key distribution. For the high speed quantum communication, photon detectors should operate at GHz-clock frequencies. We propose balanced detection circuits for GHz-clock operation of InGaAs-APD photon detectors. The balanced single photon detector operates with sinusoidal wave gating. The sinusoidal wave appearing in the output is removed by the subtraction from APD signal without sharp band-elimination filters. Omission of the sharp filters removes the constraint on the operating frequency of the single photon detector. We present two designs, one works with two identical APDs, the other with one APD and a low-pass filter. The sinusoidal gating enables to eliminate the gating noise even with the simple configuration of the latter design. We demonstrated the balanced single photon detector operating with 1.020GHz clock at 233 K, 193 K, and 186.5 K. The dark count probability was 4.0 x 10-4 counts/pulse with the quantum efficiency of 10% at 233K, and 1.6 x 10-4 counts/pulse at 186.5 K. These results were obtained with easily available APDs (NR8300FP-C.C, RENESASS) originally developed for optical time-domain reflectmeters.

  15. Single-Electron and Single-Photon Sensitivity with a Silicon Skipper CCD

    Science.gov (United States)

    Tiffenberg, Javier; Sofo-Haro, Miguel; Drlica-Wagner, Alex; Essig, Rouven; Guardincerri, Yann; Holland, Steve; Volansky, Tomer; Yu, Tien-Tien

    2017-09-01

    We have developed ultralow-noise electronics in combination with repetitive, nondestructive readout of a thick, fully depleted charge-coupled device (CCD) to achieve an unprecedented noise level of 0.068 e- rms /pixel . This is the first time that discrete subelectron readout noise has been achieved reproducible over millions of pixels on a stable, large-area detector. This enables the contemporaneous, discrete, and quantized measurement of charge in pixels, irrespective of whether they contain zero electrons or thousands of electrons. Thus, the resulting CCD detector is an ultra-sensitive calorimeter. It is also capable of counting single photons in the optical and near-infrared regime. Implementing this innovative non-destructive readout system has a negligible impact on CCD design and fabrication, and there are nearly immediate scientific applications. As a particle detector, this CCD will have unprecedented sensitivity to low-mass dark matter particles and coherent neutrino-nucleus scattering, while future astronomical applications may include direct imaging and spectroscopy of exoplanets.

  16. Single-electron and single-photon sensitivity with a silicon Skipper CCD

    Energy Technology Data Exchange (ETDEWEB)

    Tiffenberg, Javier [Fermilab; Sofo-Haro, Miguel [Balseiro Inst., San Carlos de Bariloche; Drlica-Wagner, Alex [Fermilab; Essig, Rouven [YITP, Stony Brook; Guardincerri, Yann [Fermilab; Holland, Steve [LBL, Berkeley; Volansky, Tomer [Tel Aviv U.; Yu, Tien-Tien [CERN

    2017-05-31

    We have developed a non-destructive readout system that uses a floating-gate amplifier on a thick, fully depleted charge coupled device (CCD) to achieve ultra-low readout noise of 0.068 e- rms/pix. This is the first time that discrete sub-electron readout noise has been achieved reproducibly over millions of pixels on a stable, large-area detector. This allows the precise counting of the number of electrons in each pixel, ranging from pixels with 0 electrons to more than 1500 electrons. The resulting CCD detector is thus an ultra-sensitive calorimeter. It is also capable of counting single photons in the optical and near-infrared regime. Implementing this innovative non-destructive readout system has a negligible impact on CCD design and fabrication, and there are nearly immediate scientific applications. As a particle detector, this CCD will have unprecedented sensitivity to low-mass dark matter particles and coherent neutrino-nucleus scattering, while astronomical applications include future direct imaging and spectroscopy of exoplanets.

  17. Spectrally pure heralded single photons by spontaneous four-wave mixing in a fiber: reducing impact of dispersion fluctuations

    DEFF Research Database (Denmark)

    Koefoed, Jacob Gade; Friis, Søren Michael Mørk; Christensen, Jesper Bjerge

    2017-01-01

    We model the spectral quantum-mechanical purity of heralded single photons from a photon-pair source based on nondegenerate spontaneous four-wave mixing taking the impact of distributed dispersion fluctuations into account. The considered photon-pair-generation scheme utilizes pump-pulse walk......-off to produce pure heralded photons and phase matching is achieved through the dispersion properties of distinct spatial modes in a few-mode silica step-index fiber. We show that fiber-core-radius fluctuations in general severely impact the single-photon purity. Furthermore, by optimizing the fiber design we...... show that generation of single photons with very high spectral purity is feasible even in the presence of large core-radius fluctuations. At the same time, contamination from spontaneous Raman scattering is greatly mitigated by separating the single-photon frequency by more than 32 THz from the pump...

  18. Real-Time Data Acquisition for Single Photon Imaging Detector

    Science.gov (United States)

    Hu, Kun; Wang, Xu; Yao, Yuan; Gao, Xin; Jin, Ge

    2016-04-01

    We will describe a real-time data acquisition (DAQ) system for an MCP-based photon imaging detector, which is read out with the induced charge scheme by a wedge-and-strip anode (WSA) employing position-dependent charge partitioning. The traditional filter and shaping technique is employed in the position decoding electronics. Data processing and algorithms are completely implemented via field programmable gate array (FPGA). To achieve the high-precision charge measurement and high count rate, the whole module requires good dynamic range and short dead time. The latest results show the RMS resolution of the micro channel plate (MCP) detector with an effective diameter of 30 mm can reach 60 μm in the horizontal and vertical directions, respectively. Due to the real-time imaging, the module can support count rates up to 500 kHz. However, the pulse pile-up limits the ultimate count rate.

  19. Mini-stop bands in single heterojunction photonic crystal waveguides

    KAUST Repository

    Shahid, N.

    2013-01-01

    Spectral characteristics of mini-stop bands (MSB) in line-defect photonic crystal (PhC) waveguides and in heterostructure PhC waveguides having one abrupt interface are investigated. Tunability of the MSB position by air-fill factor heterostructure PhC waveguides is utilized to demonstrate different filter functions, at optical communication wavelengths, ranging from resonance-like to wide band pass filters with high transmission. The narrowest filter realized has a resonance-like transmission peak with a full width at half maximum of 3.4 nm. These devices could be attractive for coarse wavelength selection (pass and drop) and for sensing applications. 2013 Copyright 2013 Author(s). This article is distributed under a Creative Commons Attribution 3.0 Unported License.

  20. Strong coupling of a single electron in silicon to a microwave photon

    Science.gov (United States)

    Mi, Xiao; Cady, Jeffrey; Zajac, David; Petta, Jason

    We demonstrate a hybrid circuit quantum electrodynamics (cQED) architecture in which a single electron in a Si/SiGe double quantum dot is dipole-coupled to the electric field of microwave photons in a superconducting cavity. Vacuum Rabi splitting is observed in the cavity transmission when the transition energy of the single-electron charge qubit matches that of a cavity photon, demonstrating that our device is in the strong coupling regime. The achievement of strong coupling is largely facilitated by an exceptionally low charge decoherence rate of 5 MHz and paves the way toward a wide range of cQED experiments with quantum dots, such as non-local qubit interactions, strong spin-cavity coupling and single photon generation . Research sponsored by ARO Grant No. W911NF-15-1-0149, the Gordon and Betty Moore Foundation's EPiQS Initiative through Grant GBMF4535, and the NSF (DMR-1409556 and DMR-1420541).

  1. Characterization of NbN films for superconducting nanowire single photon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Mcdonald, Ross D [Los Alamos National Laboratory; Ayala - Valenzuela, Oscar E [Los Alamos National Laboratory; Weisse - Bernstein, Nina R [Los Alamos National Laboratory; Williamson, Todd L [Los Alamos National Laboratory; Hoffbauer, M. A. [Los Alamos National Laboratory; Graf, M. J. [Los Alamos National Laboratory; Rabin, M. W. [Los Alamos National Laboratory

    2011-01-14

    Nanoscopic superconducting meander patterns offer great promise as a new class of cryogenic radiation sensors capable of single photon detection. To realize this potential, control of the superconducting properties on the nanoscale is imperative. To this end, Superconducting Nanowire Single Photon Detectors (SNSPDs) are under development by means Energetic Neutral Atom Beam Lithography and Epitaxy, or ENABLE. ENABLE can growth highly-crystalline, epitaxial thin-film materials, like NbN, at low temperatures; such wide-ranging control of fabrication parameters is enabling the optimization of film properties for single photon detection. T{sub c}, H{sub c2}, {zeta}{sub GL} and J{sub c} of multiple thin films and devices have been studied as a function of growth conditions. The optimization of which has already produced devices with properties rivaling all reports in the existing literature.

  2. Electrically driven quantum dot-micropillar single photon source with 34% overall efficiency

    Science.gov (United States)

    Heindel, T.; Schneider, C.; Lermer, M.; Kwon, S. H.; Braun, T.; Reitzenstein, S.; Höfling, S.; Kamp, M.; Forchel, A.

    2010-01-01

    We report on triggered single photon emission from low mode volume electrically driven quantum dot-micropillar cavities at repetition rates of up to 220 MHz. Due to an optimized layout of the doped planar microcavity and an advanced lateral current injection scheme, highly efficient single photon sources are realized. While g(2)(0)-values as low as 0.13±0.05 and a Purcell factor of 4 are observed for a 2.0 μm diameter micropillar, single photon emission at a rate of (35±7) MHz and an overall efficiency of (34±7)% are demonstrated for a 3.0 μm device.

  3. Single photon emission computed tomography and serial MRI in preterm infants with kernicterus.

    Science.gov (United States)

    Okumura, Akihisa; Hayakawa, Fumio; Maruyama, Koichi; Kubota, Tetsuo; Kato, Katsuhiko; Watanabe, Kazuyoshi

    2006-07-01

    Single photon emission computed tomography was performed in three preterm infants with athetoid cerebral palsy due to kernicterus. No clinical signs and symptoms of kernicterus, or ultrasonographic abnormalities were seen during the neonatal period in any patients. Although MRI during infancy revealed high intensity areas in bilateral globi pallidi in all of them, MRI abnormalities were mild in two of them. On later MRI, subtle high intensity areas in the globi pallidi were recognized in only one of them. Single photon emission computed tomography demonstrated hypoperfusion in the basal ganglia regions in all patients. Regions of interest analyses showed decreased blood flow in the basal ganglia related to the cortical areas. Single photon emission computed tomography will be useful for the diagnosis of kernicterus, whereas MRI abnormalities become less clear beyond infancy.

  4. A universal setup for active control of a single-photon detector

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qin; Skaar, Johannes [Department of Electronics and Telecommunications, Norwegian University of Science and Technology, NO-7491 Trondheim (Norway); Lamas-Linares, Antía; Kurtsiefer, Christian [Centre for Quantum Technologies and Department of Physics, National University of Singapore, 3 Science Drive 2, Singapore 117543 (Singapore); Makarov, Vadim, E-mail: makarov@vad1.com [Institute for Quantum Computing and Department of Physics and Astronomy, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1 (Canada); Gerhardt, Ilja, E-mail: ilja@quantumlah.org [Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart (Germany)

    2014-01-15

    The influence of bright light on a single-photon detector has been described in a number of recent publications. The impact on quantum key distribution (QKD) is important, and several hacking experiments have been tailored to fully control single-photon detectors. Special attention has been given to avoid introducing further errors into a QKD system. We describe the design and technical details of an apparatus which allows to attack a quantum-cryptographic connection. This device is capable of controlling free-space and fiber-based systems and of minimizing unwanted clicks in the system. With different control diagrams, we are able to achieve a different level of control. The control was initially targeted to the systems using BB84 protocol, with polarization encoding and basis switching using beamsplitters, but could be extended to other types of systems. We further outline how to characterize the quality of active control of single-photon detectors.

  5. Fluctuation mechanisms in superconductors nanowire single-photon counters, enabled by effective top-down manufacturing

    CERN Document Server

    Bartolf, Holger

    2016-01-01

    Holger Bartolf discusses state-of-the-art detection concepts based on superconducting nanotechnology as well as sophisticated analytical formulæ that model dissipative fluctuation-phenomena in superconducting nanowire single-photon detectors. Such knowledge is desirable for the development of advanced devices which are designed to possess an intrinsic robustness against vortex-fluctuations and it provides the perspective for honorable fundamental science in condensed matter physics. Especially the nanowire detector allows for ultra-low noise detection of signals with single-photon sensitivity and GHz repetition rates. Such devices have a huge potential for future technological impact and might enable unique applications (e.g. high rate interplanetary deep-space data links from Mars to Earth). Contents Superconducting Single-Photon Detectors Nanotechnological Manufacturing; Scale: 10 Nanometer Berezinskii-Kosterlitz Thouless (BKT) Transition, Edge-Barrier, Phase Slips Target Groups Researchers and students of...

  6. Large scale fabrication of nitrogen vacancy-embedded diamond nanostructures for single-photon source applications

    Science.gov (United States)

    Jiang, Qianqing; Li, Wuxia; Tang, Chengchun; Chang, Yanchun; Hao, Tingting; Pan, Xinyu; Ye, Haitao; Li, Junjie; Gu, Changzhi

    2016-11-01

    Some color centers in diamond can serve as quantum bits which can be manipulated with microwave pulses and read out with laser, even at room temperature. However, the photon collection efficiency of bulk diamond is greatly reduced by refraction at the diamond/air interface. To address this issue, we fabricated arrays of diamond nanostructures, differing in both diameter and top end shape, with HSQ and Cr as the etching mask materials, aiming toward large scale fabrication of single-photon sources with enhanced collection efficiency made of nitrogen vacancy (NV) embedded diamond. With a mixture of O2 and CHF3 gas plasma, diamond pillars with diameters down to 45 nm were obtained. The top end shape evolution has been represented with a simple model. The tests of size dependent single-photon properties confirmed an improved single-photon collection efficiency enhancement, larger than tenfold, and a mild decrease of decoherence time with decreasing pillar diameter was observed as expected. These results provide useful information for future applications of nanostructured diamond as a single-photon source. Project supported by the National Key Research and Development Plan of China (Grant No. 2016YFA0200402), the National Natural Science Foundation of China (Grants Nos. 11574369, 11574368, 91323304, 11174362, and 51272278), and the FP7 Marie Curie Action (project No. 295208) sponsored by the European Commission.

  7. Generating single photons at gigahertz modulation-speed using electrically controlled quantum dot microlenses

    Energy Technology Data Exchange (ETDEWEB)

    Schlehahn, A.; Schmidt, R.; Hopfmann, C.; Schulze, J.-H.; Strittmatter, A.; Heindel, T., E-mail: tobias.heindel@tu-berlin.de; Reitzenstein, S. [Institut für Festkörperphysik, Technische Universität Berlin, 10623 Berlin (Germany); Gantz, L.; Schmidgall, E. R.; Gershoni, D. [The Physics Department and the Solid State Institute, Technion-Israel Institute of Technology, 32000 Haifa (Israel)

    2016-01-11

    We report on the generation of single-photon pulse trains at a repetition rate of up to 1 GHz. We achieve this speed by modulating the external voltage applied on an electrically contacted quantum dot microlens, which is optically excited by a continuous-wave laser. By modulating the photoluminescence of the quantum dot microlens using a square-wave voltage, single-photon emission is triggered with a response time as short as (281 ± 19) ps, being 6 times faster than the radiative lifetime of (1.75 ± 0.02) ns. This large reduction in the characteristic emission time is enabled by a rapid capacitive gating of emission from the quantum dot, which is placed in the intrinsic region of a p-i-n-junction biased below the onset of electroluminescence. Here, since our circuit acts as a rectifying differentiator, the rising edge of the applied voltage pulses triggers the emission of single photons from the optically excited quantum dot. The non-classical nature of the photon pulse train generated at GHz-speed is proven by intensity autocorrelation measurements with g{sup (2)}(0) = 0.3 ± 0.1. Our results combine optical excitation with fast electrical gating and thus show promise for the generation of indistinguishable single photons at rates exceeding the limitations set by the intrinsic radiative lifetime.

  8. Generating single photons at gigahertz modulation-speed using electrically controlled quantum dot microlenses

    Science.gov (United States)

    Schlehahn, A.; Schmidt, R.; Hopfmann, C.; Schulze, J.-H.; Strittmatter, A.; Heindel, T.; Gantz, L.; Schmidgall, E. R.; Gershoni, D.; Reitzenstein, S.

    2016-01-01

    We report on the generation of single-photon pulse trains at a repetition rate of up to 1 GHz. We achieve this speed by modulating the external voltage applied on an electrically contacted quantum dot microlens, which is optically excited by a continuous-wave laser. By modulating the photoluminescence of the quantum dot microlens using a square-wave voltage, single-photon emission is triggered with a response time as short as (281 ± 19) ps, being 6 times faster than the radiative lifetime of (1.75 ± 0.02) ns. This large reduction in the characteristic emission time is enabled by a rapid capacitive gating of emission from the quantum dot, which is placed in the intrinsic region of a p-i-n-junction biased below the onset of electroluminescence. Here, since our circuit acts as a rectifying differentiator, the rising edge of the applied voltage pulses triggers the emission of single photons from the optically excited quantum dot. The non-classical nature of the photon pulse train generated at GHz-speed is proven by intensity autocorrelation measurements with g(2)(0) = 0.3 ± 0.1. Our results combine optical excitation with fast electrical gating and thus show promise for the generation of indistinguishable single photons at rates exceeding the limitations set by the intrinsic radiative lifetime.

  9. Coupling, controlling, and processing non-transversal photons with a single atom

    Science.gov (United States)

    Rauschenbeutel, Arno

    2014-05-01

    I will report on recent experimental investigations of the interaction between single rubidium atoms and light that is confined by continuous total internal reflection in a whispering-gallery-mode (WGM) bottle microresonator. These resonators offer the advantage of very long photon lifetimes in conjunction with near lossless in- and out-coupling of light via tapered fiber couplers. We discovered that the non-transversal polarization of WGMs fundamentally alters the physics of light-matter interaction. Taking advantage of this effect, we recently demonstrated switching of signals between two distinct optical fibers controlled by a single atom. Owing to the excellent optical properties of our bottle microresonator, the scheme yields high switching fidelities and low losses. Furthermore, we exploited the strong birefringence of the bottle microresonator and implemented a single-atom-controlled polarization flip of the light that is guided through the coupling fiber. And finally, we made use of the strong nonlinear response of the atom-resonator system and experimentally realized an optical Kerr nonlinearity at the level of single photon. Analyzing the transmitted light, we observe a nonlinear phase shift of π between the cases of one and of two photons passing the resonator. This phase shift leads to entanglement between previously independent fiber-guided photons, which we verify by performing a full quantum state tomography of the transmitted two-photon state.

  10. A finite element characterization of a commercial endlessly single-mode photonic crystal fiber: is it really single mode?

    NARCIS (Netherlands)

    Uranus, H.P.; Hoekstra, Hugo; van Groesen, Embrecht W.C.

    2007-01-01

    One of interesting properties of photonic crystal fibers (PCFs) is their possibility to be single-moded over a wide wavelength range, down to UV, while still having a reasonably large modal profile. Such properties are attractive for applications like optical sensing, interferometry, and transport

  11. Thallium-201 accumulation in cerebral candidiasis: Unexpected finding on SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Tonami, N.; Matsuda, H.; Ooba, H.; Yokoyama, K.; Hisada, K.; Ikeda, K.; Yamashita, J. (Kanazawa Univ. (Japan))

    1990-06-01

    The authors present an unexpected finding of Tl-201 uptake in the intracerebral lesions due to candidiasis. SPECT demonstrated the extent of the lesions and a high target-to-background ratio. The regions where abnormal Tl-201 accumulation was seen were nearly consistent with CT scans of those enhanced by a contrast agent. After treatment, most of the abnormal Tl-201 accumulation disappeared.

  12. Sequential thallium-201 myocardial scintigraphy after acute infarction in man

    Energy Technology Data Exchange (ETDEWEB)

    Fletcher, J.W.; Mueller, H.S.; Rao, P.S.

    1980-07-01

    Three sequential Tl-201 myocardial perfusion studies were performed in 21 patients (18 men, 3 women) with first acute transmural myocardia infarction. The Tl-201 image defect size was determined with a semiquantitative visual scoring method and temporal changes in image defect size were compared to CK-MB infarct size and enzymatic evidence of progressive myocardial necrosis and infarct extension. Progressive decreases in Tl-201 image defect size were observed and the visual score in all 21 patients decreased significantly from 6.5 +- 3.7 (mean +- SD) on day 1 to 4.9 +- 3.5 on day 12. Eleven patients without evidence of infarct extension had significantly lower infarct size, a significant decrease in visual score by the 12th day and had significantly smaller Tl-201 defects at all three study times compared to 10 patients with infarct extension. Seven of 10 (70%) with extension had an initial visual score greater than or equal to 7 compared to only 2/11 (18%) without extension. The temporal behavior of Tl-201 image defects is related to the size of the infarction and presence or absence of extension. Sequential studies comparing early initial and subsequent defect size may assist in evaluating the behavior of ischemic and infarcted myocardium in the postinfarction period.

  13. Dynamics of Single-Photon Emission from Electrically Pumped Color Centers

    Science.gov (United States)

    Khramtsov, Igor A.; Agio, Mario; Fedyanin, Dmitry Yu.

    2017-08-01

    Low-power, high-speed, and bright electrically driven true single-photon sources, which are able to operate at room temperature, are vital for the practical realization of quantum-communication networks and optical quantum computations. Color centers in semiconductors are currently the best candidates; however, in spite of their intensive study in the past decade, the behavior of color centers in electrically controlled systems is poorly understood. Here we present a physical model and establish a theoretical approach to address single-photon emission dynamics of electrically pumped color centers, which interprets experimental results. We support our analysis with self-consistent numerical simulations of a single-photon emitting diode based on a single nitrogen-vacancy center in diamond and predict the second-order autocorrelation function and other emission characteristics. Our theoretical findings demonstrate remarkable agreement with the experimental results and pave the way to the understanding of single-electron and single-photon processes in semiconductors.

  14. CdSe quantum dot in vertical ZnSe nanowire and photonic wire for efficient single-photon emission

    DEFF Research Database (Denmark)

    Cremel, Thibault; Bellet-Amalric, Edith; Cagnon, Laurent

    as a single photon source. We have grown vertically oriented ZnSe NWs (with typical diameter of 10 nm) by molecular beam epitaxy on a ZnSe(111)B buffer layer. The growth of a ZnMgSe passivating shell increases the (otherwise weak) ZnSe near-band-edge luminescence by two orders of magnitude. This has allowed...... us to observe luminescence for the first time from CdSe/ZnSe NW-QDs in the (111) direction. We managed to obtain a low NW density (~ 1 NW/4 μm2) so that single NW-QDs can be directly studied on the as-grown sample. Exciton, biexciton and charged exciton lines are clearly identified. Then we obtained...... conformal dielectric coating of Al2O3 on the NW-QDs using Atomic Layer Deposition so that a photonic wire is formed with the CdSe QD deterministically positioned on its axis. The collection enhancement effect is studied by measuring the emission (with pulse excitation, at saturation intensity) of single...

  15. MHz rate and efficient synchronous heralding of single photons at telecom wavelengths.

    Science.gov (United States)

    Pomarico, Enrico; Sanguinetti, Bruno; Guerreiro, Thiago; Thew, Rob; Zbinden, Hugo

    2012-10-08

    We report on the realization of a synchronous source of heralded single photons at telecom wavelengths with MHz heralding rates and high heralding efficiency. This source is based on the generation of photon pairs at 810 and 1550 nm via Spontaneous Parametric Down Conversion (SPDC) in a 1 cm periodically poled lithium niobate (PPLN) crystal pumped by a 532 nm pulsed laser. As high rates are fundamental for multi-photon experiments, we show that single telecom photons can be announced at 4.4 MHz rate with 45% heralding efficiency. When we focus only on the optimization of the coupling of the heralded photon, the heralding efficiency can be increased up to 80%. Furthermore, we experimentally observe that group velocity mismatch inside long crystals pumped in a pulsed mode affects the spectrum of the emitted photons and their fibre coupling efficiency. The length of the crystal in this source has been chosen as a trade off between high brightness and high coupling efficiency.

  16. Coupling of a single active nanoparticle to a polymer-based photonic structure

    Directory of Open Access Journals (Sweden)

    Dam Thuy Trang Nguyen

    2016-03-01

    Full Text Available The engineered coupling between a guest moiety (molecule, nanoparticle and the host photonic nanostructure may provide a great enhancement of the guest optical response, leading to many attractive applications. In this article, we describe briefly the basic concept and some recent progress considering the coupling of a single nanoparticle into a photonic structure. Different kinds of nanoparticles of great interest including quantum dots and nitrogen-vacancy centers in nanodiamond for single photon source, nonlinear nanoparticles for efficient nonlinear effect and sensors, magnetic nanoparticles for Kerr magneto-optical effect, and plasmonic nanoparticles for ultrafast optical switching and sensors, are briefly reviewed. We focus further on the coupling of plasmonic gold nanoparticles and polymeric photonic structures by optimizing theoretically the photonic structures and developing efficient way to realize desired hybrid structures. The simple and low-cost fabrication technique, the optical enhancement of the fluorescent nanoparticles induced by the photonic structure, as well as the limitations, challenges and appealing prospects are discussed in details.

  17. High-Efficiency Plug-and-Play Source of Heralded Single Photons

    Science.gov (United States)

    Montaut, Nicola; Sansoni, Linda; Meyer-Scott, Evan; Ricken, Raimund; Quiring, Viktor; Herrmann, Harald; Silberhorn, Christine

    2017-08-01

    Reliable generation of single photons is of key importance for fundamental physical experiments and to demonstrate quantum protocols. Waveguide-based photon-pair sources have shown great promise in this regard due to their large spectral tunability, high generation rates, and long temporal coherence of the photon wave packet. However, integrating such sources with fiber-optic networks often results in a strong degradation of performance. We answer this challenge by presenting an alignment-free source of photon pairs in the telecommunications band that maintains heralding efficiency >50 % even after fiber pigtailing, photon separation, and pump suppression. The source combines this outstanding performance in heralding efficiency with a compact, stable, and easy-to-use "plug-and-play" package: one simply connects a laser to the input and detectors to the output, and the source is ready to use. This high performance can be achieved even outside the lab without the need for alignment which makes the source extremely useful for any experiment or demonstration needing heralded single photons.

  18. Optimal entangling operations between deterministic blocks of qubits encoded into single photons

    Science.gov (United States)

    Smith, Jake A.; Kaplan, Lev

    2018-01-01

    Here, we numerically simulate probabilistic elementary entangling operations between rail-encoded photons for the purpose of scalable universal quantum computation or communication. We propose grouping logical qubits into single-photon blocks wherein single-qubit rotations and the controlled-not (cnot) gate are fully deterministic and simple to implement. Interblock communication is then allowed through said probabilistic entangling operations. We find a promising trend in the increasing probability of successful interblock communication as we increase the number of optical modes operated on by our elementary entangling operations.

  19. Temperature dependence of the single photon emission from interface-fluctuation GaN quantum dots.

    Science.gov (United States)

    Le Roux, F; Gao, K; Holmes, M; Kako, S; Arita, M; Arakawa, Y

    2017-11-23

    The temperature dependent single photon emission statistics of interface-fluctuation GaN quantum dots are reported. Quantum light emission is confirmed at temperatures up to ~77 K, by which point the background emission degrades the emission purity and results in a measured g(2) (0) in excess of 0.5. A discussion on the extent of the background contamination is also given through comparison to extensive data taken under various ambient and experimental conditions, revealing that the quantum dots themselves are emitting single photons with high purity.

  20. Short-range energy budget simulator of single photon lidar demonstrator

    Science.gov (United States)

    Murtazin, Mark V.; Prochazka, Ivan; Blazej, Josef; Pershin, Sergey M.; Lednev, Vasily N.

    2017-05-01

    The compact single photon lidar demonstrator dedicated for asteroid rendezvous missions has been designed and realized in our laboratory two years ago. The instrument provides crucial data on altitude and terrain profile for altitudes exceeding 5 km with a precision of less than 10 cm fulfilling the Rayleigh criterion. One of the calibration procedure of demonstrator is the positioning of receiver and transmitter optics related to detector and laser and the aligning of transmitter and receiver optical common paths. To improve this particular indoor calibration procedure the new simulator of single photon energy budget during short range operation has been created. The comparison of simulated and experimental data will be presented and discussed.

  1. Single photon quantum non-demolition measurements in the presence of inhomogeneous broadening

    Energy Technology Data Exchange (ETDEWEB)

    Greentree, Andrew D; Hollenberg, L C L; Prawer, S [Centre for Quantum Computer Technology, School of Physics, University of Melbourne, Melbourne, VIC 3010 (Australia); Beausoleil, R G [Hewlett-Packard Laboratories, 1501 Page Mill Rd, Palo Alto, CA 94304-1123 (United States); Munro, W J; Spiller, T P [Hewlett-Packard Laboratories, Filton Road, Stoke Gifford, Bristol BS34 8QZ (United Kingdom); Nemoto, Kae [National Institute of Informatics, 2-1-2 Hitotsubashi, Chiyoda-ku, Tokyo 101-8430 (Japan)], E-mail: andrew.greentree@ph.unimelb.edu.au

    2009-09-15

    Electromagnetically induced transparency (EIT) has often been proposed for generating nonlinear optical effects at the single photon level; in particular, as a means to effect a quantum non-demolition measurement of a single-photon field. Previous treatments have usually considered homogeneously broadened samples, but realizations in any medium will have to contend with inhomogeneous broadening. Here we reappraise an earlier scheme (Munro et al 2005 Phys. Rev. A 71 033819) with respect to inhomogeneities and show an alternative mode of operation that is preferred in an inhomogeneous environment. We further show the implications of these results on a potential implementation in diamond-containing nitrogen-vacancy colour centres.

  2. Single photon quantum non-demolition measurements in the presence of inhomogeneous broadening

    Science.gov (United States)

    Greentree, Andrew D.; Beausoleil, R. G.; Hollenberg, L. C. L.; Munro, W. J.; Nemoto, Kae; Prawer, S.; Spiller, T. P.

    2009-09-01

    Electromagnetically induced transparency (EIT) has often been proposed for generating nonlinear optical effects at the single photon level; in particular, as a means to effect a quantum non-demolition measurement of a single-photon field. Previous treatments have usually considered homogeneously broadened samples, but realizations in any medium will have to contend with inhomogeneous broadening. Here we reappraise an earlier scheme (Munro et al 2005 Phys. Rev. A 71 033819) with respect to inhomogeneities and show an alternative mode of operation that is preferred in an inhomogeneous environment. We further show the implications of these results on a potential implementation in diamond-containing nitrogen-vacancy colour centres.

  3. Single-photon pulsed-light indirect time-of-flight 3D ranging.

    Science.gov (United States)

    Bellisai, S; Bronzi, D; Villa, F A; Tisa, S; Tosi, A; Zappa, F

    2013-02-25

    "Indirect" time-of-flight is one technique to obtain depth-resolved images through active illumination that is becoming more popular in the recent years. Several methods and light timing patterns are used nowadays, aimed at improving measurement precision with smarter algorithms, while using less and less light power. Purpose of this work is to present an indirect time-of-flight imaging camera based on pulsed-light active illumination and a 32 × 32 single-photon avalanche diode array with an improved illumination timing pattern, able to increase depth resolution and to reach single-photon level sensitivity.

  4. Heralded quantum gates for atomic systems assisted by the scattering of photons off single emitters

    Science.gov (United States)

    Song, Guo-Zhu; Liu, Qian; Qiu, Jing; Yang, Guo-Jian; Alzahrani, Faris; Hobiny, Aatef; Deng, Fu-Guo; Zhang, Mei

    2017-12-01

    Quantum logic gates are essential in quantum information processing. Here, we propose three heralded schemes for universal quantum gates, including the controlled-NOT, Toffoli, and Fredkin gates on atomic systems, assisted by the scattering of photons off single emitters in one-dimensional waveguides. Interestingly, our schemes can turn faulty scattering processes of photons off atoms into the detection of the photon polarization. Furthermore, auxiliary atomic qubits are not needed and only one photon medium is adopted. With current technology, we discuss the feasibility of these universal quantum gates, concluding that they are feasible and scalable in solid-state quantum systems. We provide a different method for realizing universal quantum gates, and it may be useful in quantum information processing in the future.

  5. Single- and Two-Photon-Induced Processes at the B Factories

    Energy Technology Data Exchange (ETDEWEB)

    Li, Selina Z.; /SLAC

    2012-06-15

    We discuss single- and two-photon-induced processes in e{sup +}e{sup -} annihilations with center-of-mass energy near 10.58 GeV from the BaBar and Belle experiments. In particular, we present experimental results from two-photon physics of {gamma}{gamma} {yields} {pi}{sup 0}{pi}{sup 0} and {gamma}{gamma}* {yields} {pi}{sup 0}. We also review the observation of the Two-Virtual-Photon-Annihilation process (e{sup +}e{sup -} {yields} {rho}{sup 0}{rho}{sup 0} and e{sup +}e{sup -} {yields} {phi}{rho}{sup 0}) and the observation of e{sup +}e{sup -} {yields} {rho}{sup +}{rho}{sup -}, which should be primarily a one virtual photon process, but whose angular distributions may imply potential interference effects.

  6. Highly efficient heralded single-photon source for telecom wavelengths based on a PPLN waveguide.

    Science.gov (United States)

    Bock, Matthias; Lenhard, Andreas; Chunnilall, Christopher; Becher, Christoph

    2016-10-17

    We present the realization of a highly efficient photon pair source based on spontaneous parametric downconversion (SPDC) in a periodically poled lithium niobate (PPLN) ridge waveguide. The source is suitable for long distance quantum communication applications as the photon pairs are located at the centers of the telecommunication O- and C- band at 1312 nm and 1557 nm. The high efficiency is confirmed by a conversion efficiency of 4 × 10-6 - which is to our knowledge among the highest conversion efficiencies reported so far - and a heralding efficiency of 64.1 ± 2.1%. The heralded single-photon properties are confirmed by the measurement of the photon statistics with a Click/No-Click method as well as the heralded g(2)-function. A minimum value for g(2)(0) of 0.001 ± 0.0003 indicating clear antibunching has been observed.

  7. Compact two-photon fluorescence microscope based on a single-mode fiber coupler.

    Science.gov (United States)

    Bird, Damian; Gu, Min

    2002-06-15

    We present a two-photon fluorescence microscope based on a three-port single-mode optical fiber coupler. It is found that the coupler behaves as a low-pass filter that can deliver an ultrashort-pulsed laser beam of as much as 150 mW of power in the wavelength range from 770 to 870 nm as well as collect a two-photon fluorescence signal in the visible range. As a result of using the fiber coupler, the new two-photon imaging system exhibts a number of advantages, including a compact arrangement, freedom from vibration from lasers and electronic devices, self-alignment, reduction of multiple scattering, and an enhanced optical sectioning effect. The effectiveness of the new instrument is demonstrated with a set of three-dimensional images of biological samples. This instrument may make two-photon fluorescence endoscopy possible for in vivo medical applications.

  8. Slow light generation in single-mode rectangular core photonic crystal fiber

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, Sandeep; Saini, Than Singh; Kumar, Ajeet, E-mail: ajeetdph@gmail.com [Department of Applied Physics, Delhi Technological University (Formerly Delhi College of Engineering), Delhi-110 042 (India)

    2016-05-06

    In this paper, we have designed and analyzed a rectangular core photonic crystal fiber (PCF) in Tellurite material. For the designed photonics crystal fiber, we have calculated the values of confinement loss and effective mode area for different values of air filling fraction (d/Λ). For single mode operation of the designed photonic crystal fiber, we have taken d/Λ= 0.4 for the further calculation of stimulated Brillouin scattering based time delay. A maximum time delay of 158 ns has been achieved for input pump power of 39 mW. We feel the detailed theoretical investigations and simulations carried out in the study have the potential impact on the design and development of slow light-based photonic devices.

  9. Combined optical and single photon emission imaging: preliminary results.

    Science.gov (United States)

    Boschi, Federico; Spinelli, Antonello E; D'Ambrosio, Daniela; Calderan, Laura; Marengo, Mario; Sbarbati, Andrea

    2009-12-07

    In vivo optical imaging instruments are generally devoted to the acquisition of light coming from fluorescence or bioluminescence processes. Recently, an instrument was conceived with radioisotopic detection capabilities (Kodak in Vivo Multispectral System F) based on the conversion of x-rays from the phosphorus screen. The goal of this work is to demonstrate that an optical imager (IVIS 200, Xenogen Corp., Alameda, USA), designed for in vivo acquisitions of small animals in bioluminescent and fluorescent modalities, can even be employed to detect signals due to radioactive tracers. Our system is based on scintillator crystals for the conversion of high-energy rays and a collimator. No hardware modifications are required. Crystals alone permit the acquisition of photons coming from an in vivo 20 g nude mouse injected with a solution of methyl diphosphonate technetium 99 metastable (Tc99m-MDP). With scintillator crystals and collimators, a set of measurements aimed to fully characterize the system resolution was carried out. More precisely, system point spread function and modulation transfer function were measured at different source depths. Results show that system resolution is always better than 1.3 mm when the source depth is less than 10 mm. The resolution of the images obtained with radioactive tracers is comparable with the resolution achievable with dedicated techniques. Moreover, it is possible to detect both optical and nuclear tracers or bi-modal tracers with only one instrument.

  10. Combined optical and single photon emission imaging: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Boschi, Federico; Calderan, Laura; Sbarbati, Andrea [Department of Morphological-Biomedical Sciences, Section of Anatomy and Histology, University of Verona, Verona (Italy); Spinelli, Antonello E [Medical Physics Department, San Raffaele Scientific Institute, Milan (Italy); D' Ambrosio, Daniela; Marengo, Mario [Medical Physics Department, S. Orsola Malpighi Hospital, Bologna (Italy)], E-mail: federico.boschi@univr.it

    2009-12-07

    In vivo optical imaging instruments are generally devoted to the acquisition of light coming from fluorescence or bioluminescence processes. Recently, an instrument was conceived with radioisotopic detection capabilities (Kodak in Vivo Multispectral System F) based on the conversion of x-rays from the phosphorus screen. The goal of this work is to demonstrate that an optical imager (IVIS 200, Xenogen Corp., Alameda, USA), designed for in vivo acquisitions of small animals in bioluminescent and fluorescent modalities, can even be employed to detect signals due to radioactive tracers. Our system is based on scintillator crystals for the conversion of high-energy rays and a collimator. No hardware modifications are required. Crystals alone permit the acquisition of photons coming from an in vivo 20 g nude mouse injected with a solution of methyl diphosphonate technetium 99 metastable (Tc99m-MDP). With scintillator crystals and collimators, a set of measurements aimed to fully characterize the system resolution was carried out. More precisely, system point spread function and modulation transfer function were measured at different source depths. Results show that system resolution is always better than 1.3 mm when the source depth is less than 10 mm. The resolution of the images obtained with radioactive tracers is comparable with the resolution achievable with dedicated techniques. Moreover, it is possible to detect both optical and nuclear tracers or bi-modal tracers with only one instrument. (letter to the editor)

  11. On-Demand Single Photons with High Extraction Efficiency and Near-Unity Indistinguishability from a Resonantly Driven Quantum Dot in a Micropillar

    DEFF Research Database (Denmark)

    Ding, Xing; He, Yu; Duan, Z.-C.

    2016-01-01

    of a Purcellenhanced quantum dot-micropillar system, we deterministically generate resonance fluorescence single photons which, at π pulse excitation, have an extraction efficiency of 66%, single-photon purity of 99.1%, and photon indistinguishability of 98.5%. Such a single-photon source for the first time combines...

  12. Results on the Coherent Interaction of High Energy Electrons and Photons in Oriented Single Crystals

    CERN Document Server

    Apyan, A.; Badelek, B.; Ballestrero, S.; Biino, C.; Birol, I.; Cenci, P.; Connell, S.H.; Eichblatt, S.; Fonseca, T.; Freund, A.; Gorini, B.; Groess, R.; Ispirian, K.; Ketel, T.J.; Kononets, Yu.V.; Lopez, A.; Mangiarotti, A.; van Rens, B.; Sellschop, J.P.F.; Shieh, M.; Sona, P.; Strakhovenko, V.; Uggerhoj, E.; Uggerhj, Ulrik Ingerslev; Unel, G.; Velasco, M.; Vilakazi, Z.Z.; Wessely, O.; Kononets, Yu.V.

    2005-01-01

    The CERN-NA-59 experiment examined a wide range of electromagnetic processes for multi-GeV electrons and photons interacting with oriented single crystals. The various types of crystals and their orientations were used for producing photon beams and for converting and measuring their polarisation. The radiation emitted by 178 GeV unpolarised electrons incident on a 1.5 cm thick Si crystal oriented in the Coherent Bremsstrahlung (CB) and the String-of-Strings (SOS) modes was used to obtain multi-GeV linearly polarised photon beams. A new crystal polarimetry technique was established for measuring the linear polarisation of the photon beam. The polarimeter is based on the dependence of the Coherent Pair Production (CPP) cross section in oriented single crystals on the direction of the photon polarisation with respect to the crystal plane. Both a 1 mm thick single crystal of Germanium and a 4 mm thick multi-tile set of synthetic Diamond crystals were used as analyzers of the linear polarisation. A birefringence ...

  13. Bright Room-Temperature Single Photon Emission from Defects in Gallium Nitride

    CERN Document Server

    Berhane, Amanuel M; Bodrog, Zoltán; Fiedler, Saskia; Schröder, Tim; Triviño, Noelia Vico; Palacios, Tomás; Gali, Adam; Toth, Milos; Englund, Dirk; Aharonovich, Igor

    2016-01-01

    Single photon emitters play a central role in many photonic quantum technologies. A promising class of single photon emitters consists of atomic color centers in wide-bandgap crystals, such as diamond silicon carbide and hexagonal boron nitride. However, it is currently not possible to grow these materials as sub-micron thick films on low-refractive index substrates, which is necessary for mature photonic integrated circuit technologies. Hence, there is great interest in identifying quantum emitters in technologically mature semiconductors that are compatible with suitable heteroepitaxies. Here, we demonstrate robust single photon emitters based on defects in gallium nitride (GaN), the most established and well understood semiconductor that can emit light over the entire visible spectrum. We show that the emitters have excellent photophysical properties including a brightness in excess of 500x10^3 counts/s. We further show that the emitters can be found in a variety of GaN wafers, thus offering reliable and s...

  14. Simple Atomic Quantum Memory Suitable for Semiconductor Quantum Dot Single Photons

    Science.gov (United States)

    Wolters, Janik; Buser, Gianni; Horsley, Andrew; Béguin, Lucas; Jöckel, Andreas; Jahn, Jan-Philipp; Warburton, Richard J.; Treutlein, Philipp

    2017-08-01

    Quantum memories matched to single photon sources will form an important cornerstone of future quantum network technology. We demonstrate such a memory in warm Rb vapor with on-demand storage and retrieval, based on electromagnetically induced transparency. With an acceptance bandwidth of δ f =0.66 GHz , the memory is suitable for single photons emitted by semiconductor quantum dots. In this regime, vapor cell memories offer an excellent compromise between storage efficiency, storage time, noise level, and experimental complexity, and atomic collisions have negligible influence on the optical coherences. Operation of the memory is demonstrated using attenuated laser pulses on the single photon level. For a 50 ns storage time, we measure ηe2 e 50 ns=3.4 (3 )% end-to-end efficiency of the fiber-coupled memory, with a total intrinsic efficiency ηint=17 (3 )%. Straightforward technological improvements can boost the end-to-end-efficiency to ηe 2 e≈35 %; beyond that, increasing the optical depth and exploiting the Zeeman substructure of the atoms will allow such a memory to approach near unity efficiency. In the present memory, the unconditional read-out noise level of 9 ×10-3 photons is dominated by atomic fluorescence, and for input pulses containing on average μ1=0.27 (4 ) photons, the signal to noise level would be unity.

  15. Heterogeneous integration for on-chip quantum photonic circuits with single quantum dot devices.

    Science.gov (United States)

    Davanco, Marcelo; Liu, Jin; Sapienza, Luca; Zhang, Chen-Zhao; De Miranda Cardoso, José Vinícius; Verma, Varun; Mirin, Richard; Nam, Sae Woo; Liu, Liu; Srinivasan, Kartik

    2017-10-12

    Single-quantum emitters are an important resource for photonic quantum technologies, constituting building blocks for single-photon sources, stationary qubits, and deterministic quantum gates. Robust implementation of such functions is achieved through systems that provide both strong light-matter interactions and a low-loss interface between emitters and optical fields. Existing platforms providing such functionality at the single-node level present steep scalability challenges. Here, we develop a heterogeneous photonic integration platform that provides such capabilities in a scalable on-chip implementation, allowing direct integration of GaAs waveguides and cavities containing self-assembled InAs/GaAs quantum dots-a mature class of solid-state quantum emitter-with low-loss Si3N4 waveguides. We demonstrate a highly efficient optical interface between Si3N4 waveguides and single-quantum dots in GaAs geometries, with performance approaching that of devices optimized for each material individually. This includes quantum dot radiative rate enhancement in microcavities, and a path for reaching the non-perturbative strong-coupling regime.Effective use of single emitters in quantum photonics requires coherent emission, strong light-matter coupling, low losses and scalable fabrication. Here, Davanco et al. stride toward this goal by hybrid on-chip integration of Si3N4 waveguides and GaAs nanophotonic geometries with InAs quantum dots.

  16. Photon Cascade from a Single Crystal Phase Nanowire Quantum Dot

    DEFF Research Database (Denmark)

    Bouwes Bavinck, Maaike; Jöns, Klaus D; Zieliński, Michal

    2016-01-01

    We report the first comprehensive experimental and theoretical study of the optical properties of single crystal phase quantum dots in InP nanowires. Crystal phase quantum dots are defined by a transition in the crystallographic lattice between zinc blende and wurtzite segments and therefore offe...

  17. Angular correlation of annihilation photons in ice single crystals

    DEFF Research Database (Denmark)

    Mogensen, O. E.; Kvajic, G.; Eldrup, Morten Mostgaard

    1971-01-01

    Linear-slit angular-correlation curves were obtained at - 148 °C for the [0001], [10¯10], and [11¯20] directions in single crystals of ice. Besides the narrow central peak, pronounced narrow side peaks were also observed. They occurred at angles θ=2πℏgz/mc, where gz is the projection of reciproca...

  18. A single-photon counting “edge-on” silicon detector for synchrotron radiation mammography

    Science.gov (United States)

    Rigon, L.; Arfelli, F.; Astolfo, A.; Bergamaschi, A.; Dreossi, D.; Longo, R.; Menk, R.-H.; Schmitt, B.; Vallazza, E.; Castelli, E.

    2009-09-01

    The Phase Imaging for Clinical Application with Silicon detector and Synchrotron radiatiOn (PICASSO) project is developing an "edge-on" silicon microstrip detector for mammography with synchrotron radiation. The sensor is equipped with a fast single-photon counting electronics based on the Mythen-II application-specific integrated circuit. A first prototype has been assembled and tested at the SYnchrotron Radiation for MEdical Physics (SYRMEP) beamline at Elettra in Trieste, Italy. The first results are presented in this study including evidence of high-rate single-photon counting with negligible losses up to 1.2×10 6 incident photons per pixel per second; spatial resolution consistent with the pixel aperture (0.3 mm×0.05 mm); high-quality imaging of test-objects, obtained with a dose comparable to the one delivered in modern full-field digital mammographic systems.

  19. Surface acoustic wave regulated single photon emission from a coupled quantum dot–nanocavity system

    Energy Technology Data Exchange (ETDEWEB)

    Weiß, M.; Kapfinger, S.; Wixforth, A.; Krenner, H. J., E-mail: hubert.krenner@physik.uni-augsburg.de [Lehrstuhl für Experimentalphysik 1 and Augsburg Centre for Innovative Technologies (ACIT), Universität Augsburg, Universitätsstr. 1, 86159 Augsburg (Germany); Nanosystems Initiative Munich (NIM), Schellingstr. 4, 80799 München (Germany); Reichert, T.; Finley, J. J. [Walter Schottky Institut and Physik Department E24, TU München, Am Coulombwall 4, 85748 Garching (Germany); Nanosystems Initiative Munich (NIM), Schellingstr. 4, 80799 München (Germany); Kaniber, M. [Walter Schottky Institut and Physik Department E24, TU München, Am Coulombwall 4, 85748 Garching (Germany)

    2016-07-18

    A coupled quantum dot–nanocavity system in the weak coupling regime of cavity-quantumelectrodynamics is dynamically tuned in and out of resonance by the coherent elastic field of a f{sub SAW} ≃ 800 MHz surface acoustic wave. When the system is brought to resonance by the sound wave, light-matter interaction is strongly increased by the Purcell effect. This leads to a precisely timed single photon emission as confirmed by the second order photon correlation function, g{sup (2)}. All relevant frequencies of our experiment are faithfully identified in the Fourier transform of g{sup (2)}, demonstrating high fidelity regulation of the stream of single photons emitted by the system.

  20. Tunable single-photon multi-channel quantum router based on an optomechanical system

    Science.gov (United States)

    Ma, Peng-Cheng; Yan, Lei-Lei; Zhang, Jian; Chen, Gui-Bin; Li, Xiao-Wei; Zhan, You-Bang

    2018-01-01

    Routing of photons plays a key role in optical communication networks and quantum networks. Although the quantum routing of signals has been investigated for various systems, both in theory and experiment, the general form of a quantum router with multi-output terminals still needs to be explored. Here, we propose an experimentally accessible tunable single-photon multi-channel routing scheme using an optomechanics cavity which is Coulomb coupled to a nanomechanical resonator. The router can extract single photons from the coherent input signal and directly modulate them into three different output channels. More importantly, the two output signal frequencies can be selected by adjusting the Coulomb coupling strength. For application purposes, we justify that there is insignificant influence from the vacuum and thermal noises on the performance of the router under cryogenic conditions. Our proposal may pave a new avenue towards multi-channel routers and quantum networks.

  1. Carving complex many-atom entangled states by single-photon detection

    CERN Document Server

    Chen, Wenlan; Duan, Yiheng; Braverman, Boris; Zhang, Hao; Vuletic, Vladan

    2015-01-01

    We propose a versatile and efficient method to generate a broad class of complex entangled states of many atoms via the detection of a single photon. For an atomic ensemble contained in a strongly coupled optical cavity illuminated by weak single- or multi-frequency light, the atom-light interaction entangles the frequency spectrum of a transmitted photon with the collective spin of the atomic ensemble. Simple time-resolved detection of the transmitted photon then projects the atomic ensemble into a desired pure entangled state. Complex entangled states such as multicomponent Schroedinger cat states can be generated with high fidelity. This probabilistic but fast heralded state-carving method can be made quasi-deterministic by repeated trial and feedback, yields high success probability per trial, and can be implemented with existing technology.

  2. Surface acoustic wave regulated single photon emission from a coupled quantum dot-nanocavity system

    CERN Document Server

    Weiß, Matthias; Reichert, Thorsten; Finley, Jonathan J; Wixforth, Achim; Kaniber, Michael; Krenner, Hubert J

    2016-01-01

    A coupled quantum dot--nanocavity system in the weak coupling regime of cavity quantumelectrodynamics is dynamically tuned in and out of resonance by the coherent elastic field of a $f_{\\rm SAW}\\simeq800\\,\\mathrm{MHz}$ surface acoustic wave. When the system is brought to resonance by the sound wave, light-matter interaction is strongly increased by the Purcell effect. This leads to a precisely timed single photon emission as confirmed by the second order photon correlation function $g^{(2)}$. All relevant frequencies of our experiment are faithfully identified in the Fourier transform of $g^{(2)}$, demonstrating high fidelity regulation of the stream of single photons emitted by the system. The implemented scheme can be directly extended to strongly coupled systems and acoustically drives non-adiabatic entangling quantum gates based on Landau-Zener transitions.

  3. Photonic fractional Fourier transformer with a single dispersive device.

    Science.gov (United States)

    Cuadrado-Laborde, C; Carrascosa, A; Díez, A; Cruz, J L; Andres, M V

    2013-04-08

    In this work we used the temporal analog of spatial Fresnel diffraction to design a temporal fractional Fourier transformer with a single dispersive device, in this way avoiding the use of quadratic phase modulators. We demonstrate that a single dispersive passive device inherently provides the fractional Fourier transform of an incident optical pulse. The relationships linking the fractional Fourier transform order and scaling factor with the dispersion parameters are derived. We first provide some numerical results in order to prove the validity of our proposal, using a fiber Bragg grating as the dispersive device. Next, we experimentally demonstrate the feasibility of this proposal by using a spool of a standard optical fiber as the dispersive device.

  4. Single-photon superradiance from a quantum dot

    DEFF Research Database (Denmark)

    Tighineanu, Petru; Daveau, Raphaël Sura; Lehmann, Tau Bernstorff

    2016-01-01

    and the hole comprising the exciton gives rise to an anharmonic spectrum, which we exploit to prepare the superradiant quantum state deterministically with a laser pulse. We observe a fivefold enhancement of the oscillator strength compared to conventional quantum dots. The enhancement is limited by the base...... temperature of our cryostat and may lead to oscillator strengths above 1000 from a single quantum emitter at optical frequencies....

  5. Amplitude distributions of dark counts and photon counts in NbN superconducting single-photon detectors integrated with the HEMT readout

    Energy Technology Data Exchange (ETDEWEB)

    Kitaygorsky, J. [Kavli Institute of Nanoscience Delft, Delft University of Technology, 2600 GA Delft (Netherlands); Department of Electrical and Computer Engineering and Laboratory for Laser Energetics, University of Rochester, Rochester, NY 14627-0231 (United States); Słysz, W., E-mail: wslysz@ite.waw.pl [Institute of Electron Technology, PL-02 668 Warsaw (Poland); Shouten, R.; Dorenbos, S.; Reiger, E.; Zwiller, V. [Kavli Institute of Nanoscience Delft, Delft University of Technology, 2600 GA Delft (Netherlands); Sobolewski, Roman [Department of Electrical and Computer Engineering and Laboratory for Laser Energetics, University of Rochester, Rochester, NY 14627-0231 (United States)

    2017-01-15

    Highlights: • A new operation regime of NbN superconducting single-photon detectors (SSPDs). • A better understanding of the origin of dark counts generated by the detector. • A promise of PNR functionality in SSPD measurements. - Abstract: We present a new operation regime of NbN superconducting single-photon detectors (SSPDs) by integrating them with a low-noise cryogenic high-electron-mobility transistor and a high-load resistor. The integrated sensors are designed to get a better understanding of the origin of dark counts triggered by the detector, as our scheme allows us to distinguish the origin of dark pulses from the actual photon pulses in SSPDs. The presented approach is based on a statistical analysis of amplitude distributions of recorded trains of the SSPD photoresponse transients. It also enables to obtain information on energy of the incident photons, as well as demonstrates some photon-number-resolving capability of meander-type SSPDs.

  6. Light and molecular ions: the emergence of vacuum UV single-photon ionization in MS.

    Science.gov (United States)

    Hanley, Luke; Zimmermann, Ralf

    2009-06-01

    Thanks to recent technological advances and single-photon ionization's (SPI's) ability to detect all organics, the technique could become the long-sought universal soft ionization method. (To listen to a podcast about this feature, please go to the Analytical Chemistry Web site at pubs.acs.org/journal/ancham.).

  7. Quantum dot resonant tunneling diode single photon detector with aluminum oxide aperture defined tunneling area

    DEFF Research Database (Denmark)

    Li, H.W.; Kardynal, Beata; Ellis, D.J.P.

    2008-01-01

    Quantum dot resonant tunneling diode single photon detector with independently defined absorption and sensing areas is demonstrated. The device, in which the tunneling is constricted to an aperture in an insulating layer in the emitter, shows electrical characteristics typical of high quality res...

  8. Encapsulation of Conjugated Oligomers in Single-Walled Carbon Nanotubes : Towards Nanohybrids for Photonic Devices

    NARCIS (Netherlands)

    Loi, Maria Antonietta; Gao, Jia; Cordella, Fabrizio; Blondeau, Pascal; Menna, Enzo; Bartova, Barbora; Hebert, Cecile; Lazar, Sorin; Botton, Gianluigi A.; Milko, Matus; Ambrosch-Draxl, Claudia

    2010-01-01

    Visible-light emitting single-walled carbon nanotubes (SWNTs)/organic hybrids have been successfully synthesized and promise to be a photon source to be used in future optoelectronic devices. The nanohybrids are "peapods" having sexithiophene molecules inside the hollow space of SWNTs.

  9. Angular distribution of single-photon superradiance in a dilute and cold atomic ensemble

    Science.gov (United States)

    Kuraptsev, A. S.; Sokolov, I. M.; Havey, M. D.

    2017-08-01

    On the basis of a quantum microscopic approach we study the dynamics of the afterglow of a dilute Gaussian atomic ensemble excited by pulsed radiation. Taking into account the vector nature of the electromagnetic field we analyze in detail the angular and polarization distribution of single-photon superradiance of such an ensemble. The dependence of the angular distribution of superradiance on the length of the pulse and its carrier frequency as well as on the size and the shape of the atomic clouds is studied. We show that there is substantial dependence of the superradiant emission on the polarization and the direction of fluorescence. We observe essential peculiarities of superradiance in the region of the forward diffraction zone and in the area of the coherent backscattering cone. We demonstrate that there are directions for which the rate of fluorescence is several times more than the decay rate of the timed-Dicke state. We show also that single-photon superradiance can be excited by incoherent excitation when atomic polarization in the ensemble is absent. Besides a quantum microscopic approach, we analyze single-photon superradiance on the basis of the theory of incoherent multiple scattering in optically thick media (random walk theory). In the case of very short resonant and long nonresonant pulses we derive simple analytical expressions for the decay rate of single-photon superradiance for incoherent fluorescence in an arbitrary direction.

  10. Quantum dot-micropillars: a bright source of coherent single photons

    DEFF Research Database (Denmark)

    Unsleber, Sebastian; He, Yu-Ming; Maier, Sebastian

    2016-01-01

    We present the efficient generation of coherent single photons based on quantum dots in micropillars. We utilize a scalable lithography scheme leading to quantum dot-micropillar devices with 74% extraction efficiency. Via pulsed strict resonant pumping, we show an indistinguishability...

  11. Singlet oxygen luminescence detection with a fiber-coupled superconducting nanowire single-photon detector

    NARCIS (Netherlands)

    Gemmell, N.R.; McCarthy, A.; Liu, B.; Tanner, M.G.; Dorenbos, S.N.; Zwiller, V.; Patterson, M.S.; Buller, G.S.; Wilson, B.C.; Hadfield, R.H.

    2013-01-01

    Direct monitoring of singlet oxygen (1O2) luminescence is a particularly challenging infrared photodetection problem. 1O2, an excited state of the oxygen molecule, is a crucial intermediate in many biological processes. We employ a low noise superconducting nanowire single-photon detector to record

  12. Two-photon luminescence and stimulated emission depletion with gold nanorods by a single wavelength

    Science.gov (United States)

    Chen, Jianling; You, Minghai; Peng, Yiru; Yang, Hongqin; Xie, Shusen

    2017-06-01

    Single-wavelength two photon STED technique simplifies common STED setup, and decreases the cost of the system. However, this technique limits the fluorescent dye to a few kinds. Because the dye should be excited and depleted by the same single wavelength laser. And the gold nanorods can be excited by near-infrared pulsed laser and produces two photon luminescence, which is brighter than general two-photon autofluorescence by three orders. We found that the gold nanorods can also be depleted by near-infrared pulsed laser. We studied the stimulated emission depletion of gold nanorods with a single wavelength laser in the near infrared. Two photon luminescence was excited with a femtosecond pulse, then depleted by stimulated emission with a stretched pulse. The depletion efficiency with different wavelength was measured to pick out the optimal wavelength. We showed that this method can be applied to super-resolved STED microscopy, which combines the high brightness of the nanorods and the simplicity of the single-wavelength STED system.

  13. Multi-mode to single-mode conversion in a 61 port photonic lantern

    DEFF Research Database (Denmark)

    Noordegraaf, Danny; Skovgaard, Peter M.W.; Maack, Martin D.

    2010-01-01

    Efficient multi-mode (MM) to single-mode (SM) conversion in a 61 port splitter or “Photonic Lantern” is demonstrated. The coupling loss from a 100 µm core diameter MM section to an ensemble of 61 SM fibers and back to another 100 µm core MM section is measured to be as low as 0.76 d...

  14. Cross-correlated imaging of single-mode photonic crystal rod fiber with distributed mode filtering

    DEFF Research Database (Denmark)

    Laurila, Marko; Barankov, Roman; Jørgensen, Mette Marie

    2013-01-01

    Photonic crystal bandgap fibers employing distributed mode filtering design provide near diffraction-limited light outputs, a critical property of fiber-based high-power lasers. Microstructure of the fibers is tailored to achieve single-mode operation at specific wavelength by resonant mode coupl...

  15. Fluorescence lifetime imaging using a single photon avalanche diode array sensor (Conference Presentation)

    Science.gov (United States)

    Wargocki, Piotr M.; Spence, David J.; Goldys, Ewa M.; Charbon, Edoardo; Bruschini, Claudio E.; Antalović, Ivan Michel; Burri, Samuel

    2017-02-01

    Single photon detectors allows us work with the weakest fluorescence signals. Single photon arrays, combined with ps-controlled gating allow us to create image maps of fluorescence lifetimes, which can be used for in-vivo discrimination of tissue activity. Here we present fluorescence lifetime imaging using the `SwissSPAD' sensor, a 512-by-128-pixel array of gated single photon detectors, fabricated in a standard high-voltage 0.35 μm CMOS process. We present a protocol for spatially resolved lifetime measurements where the lifetime can be retrieved for each pixel. We demonstrate the system by imaging patterns of Fluorescein and Rhodamine B on test slides, as well as measuring mixed samples to retrieve both components of the decay lifetime. The single photon sensitivity of the sensor creates a valuable instrument to perform live cell or live animal (in vivo) measurements of the weak autofluorescent signals, for example distinguishing unlabelled free and bound NADH. Our ultimate goal is to create a real time fluorescence lifetime imaging system, possibly integrated into augmented reality goggles, which could allow immediate discrimination of in vivo tissues.

  16. A near-infrared 64-pixel superconducting nanowire single photon detector array with integrated multiplexed readout

    Energy Technology Data Exchange (ETDEWEB)

    Allman, M. S., E-mail: shane.allman@boulder.nist.gov; Verma, V. B.; Stevens, M.; Gerrits, T.; Horansky, R. D.; Lita, A. E.; Mirin, R.; Nam, S. W. [National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305-3328 (United States); Marsili, F.; Beyer, A.; Shaw, M. D. [Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, California 91109 (United States); Kumor, D. [Purdue University, 610 Purdue Mall, West Lafayette, Indiana 47907 (United States)

    2015-05-11

    We demonstrate a 64-pixel free-space-coupled array of superconducting nanowire single photon detectors optimized for high detection efficiency in the near-infrared range. An integrated, readily scalable, multiplexed readout scheme is employed to reduce the number of readout lines to 16. The cryogenic, optical, and electronic packaging to read out the array as well as characterization measurements are discussed.

  17. Frequency up-conversion based single photon, mid-IR spectral imaging with 20% quantum efficiency

    DEFF Research Database (Denmark)

    Tidemand-Lichtenberg, Peter; Dam, Jeppe Seidelin; Pedersen, Christian

    Spectral imaging of mid-infrared (mid-IR) light is emerging as a promising technology since important chemical compounds display unique and strong mid-IR spectral fingerprints. We demonstrate for detection a novel method including a field deployable imaging system with single photon sensitivity...

  18. QUANTUM CRYPTOGRAPHY SYSTEM WITH A SINGLE PHOTON SOURCE BASED ON THE SPONTANEOUS PARAMETRIC SCATTERING EFFECT

    Directory of Open Access Journals (Sweden)

    V. I. Egorov

    2012-01-01

    Full Text Available A scheme of a single photon source for quantum informatics applications based on the spontaneous parametric scattering effect is proposed and a quantum cryptography setup using it is presented. The system is compared to the alternative ones that operate with attenuated classic light.

  19. Controlling single-photon Fock-state propagation through opaque scattering media

    NARCIS (Netherlands)

    Huisman, T.J.; Huisman, T.J.; Huisman, S.R.; Mosk, Allard; Pinkse, Pepijn Willemszoon Harry

    2014-01-01

    The control of light scattering is essential in many quantum optical experiments. Wavefront shaping is a technique used for ultimate control over wave propagation through multiple-scattering media by adaptive manipulation of incident waves. We control the propagation of single-photon Fock states

  20. Extremely low-loss single-mode photonic crystal fiber in the terahertz regime

    DEFF Research Database (Denmark)

    Islam, Raonaqul; Hasanuzzaman, G. K M; Sadath, Md Anwar

    2015-01-01

    This paper presents an updated design and numerical characterization of a rotated porous-core hexagonal photonic crystal fiber (PCF) for single-mode terahertz (THz) wave guidance. The simulation results are found using an efficient finite element method (FEM) which show a better and ultra...

  1. Flat-top Drop Filter based on a Single Topology Optimized Photonic Crystal Cavity

    DEFF Research Database (Denmark)

    Frandsen, Lars Hagedorn; Elesin, Yuriy; Guan, Xiaowei

    2015-01-01

    Outperforming conventional design concepts, a flat-top drop filter has been designed byapplying 3D topology optimization to a single waveguide-coupled L3 photonic crystal cavity.Measurements on the design fabricated in silicon-on-insulator material reveal that the pass-band ofthe drop channel...

  2. Highly anisotropic decay rates of single quantum dots in photonic crystal membranes

    DEFF Research Database (Denmark)

    Wang, Qin; Stobbe, Søren; Nielsen, Henri Thyrrestrup

    2010-01-01

    We have measured the variation of the spontaneous emission rate with polarization for self-assembled single quantum dots in two-dimensional photonic crystal membranes. We observe a maximum anisotropy factor of 6 between the decay rates of the two bright exciton states. This large anisotropy...

  3. Experimental demonstration of highly anisotropic decay rates of single quantum dots inside photonic crystals

    DEFF Research Database (Denmark)

    Wang, Qin; Stobbe, Søren; Nielsen, Henri Thyrrestrup

    We have systematically measured the variation of the spontaneous emission rate with polarization for self-assembled single quantum dots in two-dimensional photonic crystal membranes and obtained a maximum anisotropy factor of 6 between the decay rates of the two nondegenerate bright exciton states....

  4. 3D near-infrared imaging based on a single-photon avalanche diode array sensor

    NARCIS (Netherlands)

    Mata Pavia, J.; Charbon, E.; Wolf, M.

    2011-01-01

    An imager for optical tomography was designed based on a detector with 128x128 single-photon pixels that included a bank of 32 time-to-digital converters. Due to the high spatial resolution and the possibility of performing time resolved measurements, a new contact-less setup has been conceived in

  5. High-fidelity teleportation of continuous-variable quantum States using delocalized single photons

    DEFF Research Database (Denmark)

    Andersen, Ulrik L; Ralph, Timothy C

    2013-01-01

    states as in traditional teleportation but on an ensemble of single photon entangled states. We characterize the teleportation scheme with coherent states, mesoscopic superposition states, and two-mode squeezed states and we find several situations in which near-unity teleportation fidelity can...

  6. Optical Field-Strength Polarization of Two-Mode Single-Photon States

    Science.gov (United States)

    Linares, J.; Nistal, M. C.; Barral, D.; Moreno, V.

    2010-01-01

    We present a quantum analysis of two-mode single-photon states based on the probability distributions of the optical field strength (or position quadrature) in order to describe their quantum polarization characteristics, where polarization is understood as a significative confinement of the optical field-strength values on determined regions of…

  7. A new single-photon avalanche diode in 90nm standard CMOS technology

    NARCIS (Netherlands)

    Karami, M.A.; Gersbach, M.; Yoon, H.J.; Charbon, E.

    2010-01-01

    We report on the first implementation of a single-photon avalanche diode (SPAD) in 90nm complementary metal oxide semiconductor (CMOS) technology. The detector features an octagonal multiplication region and a guard ring to prevent premature edge breakdown using a standard mask set exclusively. The

  8. Characterizing time decay of bibenzyl scintillator using time correlated single photon counting

    Energy Technology Data Exchange (ETDEWEB)

    Hatarik, R.; Bernstein, L. A.; Caggiano, J. A.; Carman, M. L.; Schneider, D. H. G.; Zaitseva, N. P. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Wiedeking, M. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); iThemba LABS, P.O. Box 722, 7129 Somerset West (South Africa)

    2012-10-15

    The time decay of several scintillation materials has been measured using the time correlated single photon counting method and a new organic crystal with a highly suppressed delayed light has been identified. Results comparing the light decay of the bibenzyl crystal with a xylene based detector, which is currently installed at National Ignition Facility will be presented.

  9. Extraction of the beta-factor for single quantum dots coupled to a photonic crystal waveguide

    DEFF Research Database (Denmark)

    Nielsen, Henri Thyrrestrup; Sapienza, Luca; Lodahl, Peter

    2010-01-01

    We present measurements of the β-factor, describing the coupling efficiency of light emitted by single InAs/GaAs semiconductor quantum dots into a photonic crystal waveguide mode. The β-factor is evaluated by means of time resolved frequency-dependent photoluminescence spectroscopy. The emission...

  10. Integration of Single-Photon Sources and Detectors on GaAs

    Directory of Open Access Journals (Sweden)

    Giulia Enrica Digeronimo

    2016-10-01

    Full Text Available Quantum photonic integrated circuits (QPICs on a GaAs platform allow the generation, manipulation, routing, and detection of non-classical states of light, which could pave the way for quantum information processing based on photons. In this article, the prototype of a multi-functional QPIC is presented together with our recent achievements in terms of nanofabrication and integration of each component of the circuit. Photons are generated by excited InAs quantum dots (QDs and routed through ridge waveguides towards photonic crystal cavities acting as filters. The filters with a transmission of 20% and free spectral range ≥66 nm are able to select a single excitonic line out of the complex emission spectra of the QDs. The QD luminescence can be measured by on-chip superconducting single photon detectors made of niobium nitride (NbN nanowires patterned on top of a suspended nanobeam, reaching a device quantum efficiency up to 28%. Moreover, two electrically independent detectors are integrated on top of the same nanobeam, resulting in a very compact autocorrelator for on-chip g(2(τ measurements.

  11. Probing single-photon ionization on the attosecond time scale

    CERN Document Server

    Klünder, K; Gisselbrecht, M; Fordell, T; Swoboda, M; Guénot, D; Johnsson, P; Caillat, J; Mauritsson, J; Maquet, A; Taïeb, R; L'Huillier, A

    2010-01-01

    We study photoionization of argon atoms excited by attosecond pulses using an interferometric measurement technique. We measure the difference in time delays between electrons emitted from the $3s^2$ and from the $3p^6$ shell, at different excitation energies ranging from 32 to 42 eV. The determination of single photoemission time delays requires to take into account the measurement process, involving the interaction with a probing infrared field. This contribution can be estimated using an universal formula and is found to account for a substantial fraction of the measured delay.

  12. Modeling of plasmon mediated single-photon devices

    DEFF Research Database (Denmark)

    Chen, Yuntian

    The thesis describes the theoretical study of optical plasmons mediated light-matter interaction. We develop a finite element method to study spontaneous emission from emitters coupled to plasmonic waveguides. The numerical method is applied to calculate the coupling of a emitter coupled to a cyl......-based reconfigurable antenna to controllably distribute emission from a single emitter in spatially separated channels....... to a cylindrical nanowire, a square metallic nanowire and a metallic slot waveguide with inhomogenous dielectric environment. We also examine a quantum emitter coupled to optical nanoantennas. We mimic the conventional Yagi-Uda to realize its optical analogy for directional emission. We also propose a plasmon...

  13. Bandwidth comparison of photonic crystal fibers and conventional single mode fibers

    DEFF Research Database (Denmark)

    Nielsen, Martin Dybendal; Folkenberg, Jacob Riis; Mortensen, Niels Asger

    2004-01-01

    We experimentally compare the optical bandwidth of a conventional single-mode fiber (SMF) with 3 different photonic crystal fibers (PCF) all optimized for visible applications. The spectral attenuation, single-turn bend loss, and mode-field diameters (MFD) are measured and the PCF is found to have...... a significantly larger bandwidth than the SMF for an identical MFD. It is shown how this advantage can be utilized for realizing a larger MFD for the PCF while maintaining a bending resistant fiber....

  14. Radio frequency phototube and optical clock: High resolution, high rate and highly stable single photon timing technique

    Energy Technology Data Exchange (ETDEWEB)

    Margaryan, Amur

    2011-10-01

    A new timing technique for single photons based on the radio frequency phototube and optical clock or femtosecond optical frequency comb generator is proposed. The technique has a 20 ps resolution for single photons, is capable of operating with MHz frequencies and achieving 10 fs instability level.

  15. Quantum detector tomography of a time-multiplexed superconducting nanowire single-photon detector at telecom wavelengths

    NARCIS (Netherlands)

    Natarajan, C.M.; Zhang, L.; Coldenstrodt-Ronge, H.; Donati, G.; Dorenbos, S.N.; Zwiller, V.; Walmsley, I.A.; Hadfield, R.H.

    2013-01-01

    Superconducting nanowire single-photon detectors (SNSPDs) are widely used in telecom wavelength optical quantum information science applications. Quantum detector tomography allows the positive-operator-valued measure (POVM) of a single-photon detector to be determined. We use an all-fiber telecom

  16. Enhanced telecom wavelength single-photon detection with NbTiN superconducting nanowires on oxidized silicon

    NARCIS (Netherlands)

    Tanner, M.G.; Natarajan, C.M.; Pottapenjara, V.K.; O'Connor, J.A.; Warburton, R.J.; Hadfield, R.H.; Baek, B.; Nam, S.; Dorenbos, S.N.; Bermúdez Ureña, E.; Zijlstra, T.; Klapwijk, T.M.; Zwiller, V.

    2010-01-01

    Superconducting nanowire single-photon detectors (SNSPDs) have emerged as a highly promising infrared single-photon detector technology. Next-generation devices are being developed with enhanced detection efficiency (DE) at key technological wavelengths via the use of optical cavities. Furthermore,

  17. Design and Performance of an InGaAs-InP Single-Photon Avalanche Diode Detector

    OpenAIRE

    Pellegrini, Sara; Warburton, Ryan E; Tan, Lionel J. J.; Ng, Jo Shien; Krysa, Andrey B.; Groom, Kristian; David, John P R; Cova, Sergio; Robertson, Michael J.; Buller, Gerald S.

    2006-01-01

    This paper describes the design, fabrication, and performance of planar-geometry InGaAs-InP devices which were specifically developed for single-photon detection at a wavelength of 1550 nm. General performance issues such as dark count rate, single-photon detection efficiency, afterpulsing, and jitter are described.

  18. Development of new photon-counting detectors for single-molecule fluorescence microscopy

    Science.gov (United States)

    Michalet, X.; Colyer, R. A.; Scalia, G.; Ingargiola, A.; Lin, R.; Millaud, J. E.; Weiss, S.; Siegmund, Oswald H. W.; Tremsin, Anton S.; Vallerga, John V.; Cheng, A.; Levi, M.; Aharoni, D.; Arisaka, K.; Villa, F.; Guerrieri, F.; Panzeri, F.; Rech, I.; Gulinatti, A.; Zappa, F.; Ghioni, M.; Cova, S.

    2013-01-01

    Two optical configurations are commonly used in single-molecule fluorescence microscopy: point-like excitation and detection to study freely diffusing molecules, and wide field illumination and detection to study surface immobilized or slowly diffusing molecules. Both approaches have common features, but also differ in significant aspects. In particular, they use different detectors, which share some requirements but also have major technical differences. Currently, two types of detectors best fulfil the needs of each approach: single-photon-counting avalanche diodes (SPADs) for point-like detection, and electron-multiplying charge-coupled devices (EMCCDs) for wide field detection. However, there is room for improvements in both cases. The first configuration suffers from low throughput owing to the analysis of data from a single location. The second, on the other hand, is limited to relatively low frame rates and loses the benefit of single-photon-counting approaches. During the past few years, new developments in point-like and wide field detectors have started addressing some of these issues. Here, we describe our recent progresses towards increasing the throughput of single-molecule fluorescence spectroscopy in solution using parallel arrays of SPADs. We also discuss our development of large area photon-counting cameras achieving subnanosecond resolution for fluorescence lifetime imaging applications at the single-molecule level. PMID:23267185

  19. Silicon photon-counting avalanche diodes for single-molecule fluorescence spectroscopy.

    Science.gov (United States)

    Michalet, Xavier; Ingargiola, Antonino; Colyer, Ryan A; Scalia, Giuseppe; Weiss, Shimon; Maccagnani, Piera; Gulinatti, Angelo; Rech, Ivan; Ghioni, Massimo

    2014-11-01

    Solution-based single-molecule fluorescence spectroscopy is a powerful experimental tool with applications in cell biology, biochemistry and biophysics. The basic feature of this technique is to excite and collect light from a very small volume and work in a low concentration regime resulting in rare burst-like events corresponding to the transit of a single molecule. Detecting photon bursts is a challenging task: the small number of emitted photons in each burst calls for high detector sensitivity. Bursts are very brief, requiring detectors with fast response time and capable of sustaining high count rates. Finally, many bursts need to be accumulated to achieve proper statistical accuracy, resulting in long measurement time unless parallelization strategies are implemented to speed up data acquisition. In this paper we will show that silicon single-photon avalanche diodes (SPADs) best meet the needs of single-molecule detection. We will review the key SPAD parameters and highlight the issues to be addressed in their design, fabrication and operation. After surveying the state-of-the-art SPAD technologies, we will describe our recent progress towards increasing the throughput of single-molecule fluorescence spectroscopy in solution using parallel arrays of SPADs. The potential of this approach is illustrated with single-molecule Förster resonance energy transfer measurements.

  20. Silicon photon-counting avalanche diodes for single-molecule fluorescence spectroscopy

    Science.gov (United States)

    Michalet, Xavier; Ingargiola, Antonino; Colyer, Ryan A.; Scalia, Giuseppe; Weiss, Shimon; Maccagnani, Piera; Gulinatti, Angelo; Rech, Ivan; Ghioni, Massimo

    2014-01-01

    Solution-based single-molecule fluorescence spectroscopy is a powerful experimental tool with applications in cell biology, biochemistry and biophysics. The basic feature of this technique is to excite and collect light from a very small volume and work in a low concentration regime resulting in rare burst-like events corresponding to the transit of a single molecule. Detecting photon bursts is a challenging task: the small number of emitted photons in each burst calls for high detector sensitivity. Bursts are very brief, requiring detectors with fast response time and capable of sustaining high count rates. Finally, many bursts need to be accumulated to achieve proper statistical accuracy, resulting in long measurement time unless parallelization strategies are implemented to speed up data acquisition. In this paper we will show that silicon single-photon avalanche diodes (SPADs) best meet the needs of single-molecule detection. We will review the key SPAD parameters and highlight the issues to be addressed in their design, fabrication and operation. After surveying the state-of-the-art SPAD technologies, we will describe our recent progress towards increasing the throughput of single-molecule fluorescence spectroscopy in solution using parallel arrays of SPADs. The potential of this approach is illustrated with single-molecule Förster resonance energy transfer measurements. PMID:25309114

  1. Development of new photon-counting detectors for single-molecule fluorescence microscopy.

    Science.gov (United States)

    Michalet, X; Colyer, R A; Scalia, G; Ingargiola, A; Lin, R; Millaud, J E; Weiss, S; Siegmund, Oswald H W; Tremsin, Anton S; Vallerga, John V; Cheng, A; Levi, M; Aharoni, D; Arisaka, K; Villa, F; Guerrieri, F; Panzeri, F; Rech, I; Gulinatti, A; Zappa, F; Ghioni, M; Cova, S

    2013-02-05

    Two optical configurations are commonly used in single-molecule fluorescence microscopy: point-like excitation and detection to study freely diffusing molecules, and wide field illumination and detection to study surface immobilized or slowly diffusing molecules. Both approaches have common features, but also differ in significant aspects. In particular, they use different detectors, which share some requirements but also have major technical differences. Currently, two types of detectors best fulfil the needs of each approach: single-photon-counting avalanche diodes (SPADs) for point-like detection, and electron-multiplying charge-coupled devices (EMCCDs) for wide field detection. However, there is room for improvements in both cases. The first configuration suffers from low throughput owing to the analysis of data from a single location. The second, on the other hand, is limited to relatively low frame rates and loses the benefit of single-photon-counting approaches. During the past few years, new developments in point-like and wide field detectors have started addressing some of these issues. Here, we describe our recent progresses towards increasing the throughput of single-molecule fluorescence spectroscopy in solution using parallel arrays of SPADs. We also discuss our development of large area photon-counting cameras achieving subnanosecond resolution for fluorescence lifetime imaging applications at the single-molecule level.

  2. Single-photon superradiance and cooperative Lamb shift in an optoelectronic device (Conference Presentation)

    Science.gov (United States)

    Sirtori, Carlo

    2017-02-01

    Superradiance is one of the many fascinating phenomena predicted by quantum electrodynamics that have first been experimentally demonstrated in atomic systems and more recently in condensed matter systems like quantum dots, superconducting q-bits, cyclotron transitions and plasma oscillations in quantum wells (QWs). It occurs when a dense collection of N identical two-level emitters are phased via the exchange of photons, giving rise to enhanced light-matter interaction, hence to a faster emission rate. Of great interest is the regime where the ensemble interacts with one photon only and therefore all of the atoms, but one, are in the ground state. In this case the quantum superposition of all possible configurations produces a symmetric state that decays radiatively with a rate N times larger than that of the individual oscillators. This phenomenon, called single photon superradiance, results from the exchange of real photons among the N emitters. Yet, to single photon superradiance is also associated another collective effect that renormalizes the emission frequency, known as cooperative Lamb shift. In this work, we show that single photon superradiance and cooperative Lamb shift can be engineered in a semiconductor device by coupling spatially separated plasma resonances arising from the collective motion of confined electrons in QWs. These resonances hold a giant dipole along the growth direction z and have no mutual Coulomb coupling. They thus behave as a collection of macro-atoms on different positions along the z axis. Our device is therefore a test bench to simulate the low excitation regime of quantum electrodynamics.

  3. Growth of bulk single crystals of urea for photonic applications

    Science.gov (United States)

    Saranraj, Arumugam; Sathiyadhas, Sahaya Jude Dhas; Jose, Michael; Martin Britto Dhas, Sathiyadhas Amalapusham

    2017-08-01

    We report the growth of technologically important urea crystals of record size (48 × 16 × 8 mm3) by doping sulfuric acid and employing slow evaporation technique. The grown crystal was identified by single crystal X-Ray diffraction and FTIR spectral analysis. Optical properties of the grown crystal were analyzed by UV-Vis spectrum and the presence of H2SO4 was confirmed by EDAX analysis. Thermogravimetric analysis, Differential Scanning Calorimetry and Photo acoustic studies were also carried out to determine the thermal properties of the grown crystal. The dielectric properties for wide range of frequencies (1 Hz to 1 MHz) at different temperatures (35, 40, 60, 80, 100 °C) were analyzed. The second harmonic conversion efficiency of the grown H2SO4 doped urea crystal was found to be 3.75 times higher than the commercially available KDP crystals. [Figure not available: see fulltext.

  4. Growth of bulk single crystals of urea for photonic applications

    Science.gov (United States)

    Saranraj, Arumugam; Dhas, Sathiyadhas Sahaya Jude; Jose, Michael; Martin Britto Dhas, Sathiyadhas Amalapusham

    2018-01-01

    We report the growth of technologically important urea crystals of record size (48 × 16 × 8 mm3) by doping sulfuric acid and employing slow evaporation technique. The grown crystal was identified by single crystal X-Ray diffraction and FTIR spectral analysis. Optical properties of the grown crystal were analyzed by UV-Vis spectrum and the presence of H2SO4 was confirmed by EDAX analysis. Thermogravimetric analysis, Differential Scanning Calorimetry and Photo acoustic studies were also carried out to determine the thermal properties of the grown crystal. The dielectric properties for wide range of frequencies (1 Hz to 1 MHz) at different temperatures (35, 40, 60, 80, 100 °C) were analyzed. The second harmonic conversion efficiency of the grown H2SO4 doped urea crystal was found to be 3.75 times higher than the commercially available KDP crystals. [Figure not available: see fulltext.

  5. Single Cesium Lead Halide Perovskite Nanocrystals at Low Temperature: Fast Single-Photon Emission, Reduced Blinking, and Exciton Fine Structure.

    Science.gov (United States)

    Rainò, Gabriele; Nedelcu, Georgian; Protesescu, Loredana; Bodnarchuk, Maryna I; Kovalenko, Maksym V; Mahrt, Rainer F; Stöferle, Thilo

    2016-02-23

    Metal-halide semiconductors with perovskite crystal structure are attractive due to their facile solution processability, and have recently been harnessed very successfully for high-efficiency photovoltaics and bright light sources. Here, we show that at low temperature single colloidal cesium lead halide (CsPbX3, where X = Cl/Br) nanocrystals exhibit stable, narrow-band emission with suppressed blinking and small spectral diffusion. Photon antibunching demonstrates unambiguously nonclassical single-photon emission with radiative decay on the order of 250 ps, representing a significant acceleration compared to other common quantum emitters. High-resolution spectroscopy provides insight into the complex nature of the emission process such as the fine structure and charged exciton dynamics.

  6. Impact of the dark path on quantum dot single photon emitters in small cavities

    Science.gov (United States)

    Kamide, Kenji; Iwamoto, Satoshi; Arakawa, Yasuhiko

    2014-10-01

    Incoherent pumping in quantum dots can create a biexciton state through two paths: via the formation of bright or dark exciton states. The latter, dark-pumping path is shown to enhance the probability of two-photon simultaneous emission and hence increase g(2)(0) by a factor ∝1/γS, due to the slow spin relaxation rate γS in quantum dots. The existence of the dark path is shown to impose a limitation on the single photon emission process, especially in nanocavities which exhibit a large exciton-cavity coupling and a Purcell enhancement for fast quantum telecommunications.

  7. Integrated single- and two-photon light sheet microscopy using accelerating beams

    DEFF Research Database (Denmark)

    Piksarv, Peeter; Marti, Dominik; Le, Tuan

    2017-01-01

    We demonstrate the first light sheet microscope using propagation invariant, accelerating Airy beams that operates both in single- and two-photon modes. The use of the Airy beam permits us to develop an ultra compact, high resolution light sheet system without beam scanning. In two-photon mode......, an increase in the field of view over the use of a standard Gaussian beam by a factor of six is demonstrated. This implementation for light sheet microscopy opens up new possibilities across a wide range of biomedical applications, especially for the study of neuronal processes....

  8. Single passband microwave photonic filter using continuous-time impulse response.

    Science.gov (United States)

    Huang, Thomas X H; Yi, Xiaoke; Minasian, Robert A

    2011-03-28

    A single passband microwave photonic signal processor based on continuous time impulse response that has high resolution, multiple-taps and baseband-free response as well as exhibiting a square-top passband and tunability, is presented. The design and synthesis of the frequency response are based on a full systematic model for single passband microwave photonic filters to account for arbitrary spectrum slice shapes, which for the first time investigates the combined effects from both the dispersion-induced carrier suppression effect and the RF decay effect due to the spectrum slice width, to enable the optimum design to be realized by utilizing the carrier suppression effect to improve the filter performance. Experimental results demonstrate a high order microwave filter showing high resolution single passband filtering as well as exhibiting reconfiguration, square-top passband and tunability, for the first time to our best knowledge.

  9. Timing discriminator based on single-flux-quantum circuit toward high time-resolved photon detection

    Science.gov (United States)

    Miyajima, Shigeyuki; Miki, Shigehito; Yabuno, Masahiro; Yamashita, Taro; Terai, Hirotaka

    2017-12-01

    We propose a new time discriminating method based on a single-flux quantum (SFQ) circuit to realize a high time-resolved single-photon detection scheme that uses a superconducting nanowire single-photon detector (SSPD). The timing discriminator consists of an SFQ comparator and an interface circuit for converting the output signals of an SSPD into SFQ pulses. Prior to connecting with the SSPD, we evaluated the timing jitters of the SFQ timing discriminator itself by applying external electrical pulses. The timing jitters of the SFQ timing discriminator were found to be dominated by the timing jitters in the interface circuit. However, it was estimated to be below 10 ps even with an input pulse amplitude of 20 μA, which is close to the typical output amplitude of the SSPD.

  10. Observation of optical-fiber Kerr nonlinearity at the single-photon level

    CERN Document Server

    Matsuda, Nobuyuki; Mitsumori, Yasuyoshi; Kosaka, Hideo; Edamatsu, Keiichi; 10.1038/nphoton.2008.292

    2012-01-01

    Optical fibers have been enabling numerous distinguished applications involving the operation and generation of light, such as soliton transmission, light amplification, all-optical switching and supercontinuum generation. The active function of optical fibers in the quantum regime is expected to be applicable to ultralow-power all-optical signal processing and quantum information processing. Here we demonstrate the first experimental observation of optical nonlinearity at the single-photon level in an optical fiber. Taking advantage of large nonlinearity and managed dispersion of a photonic crystal fiber, we have successfully measured very small (10^(-7) ~ 10^(-8)) conditional phase shifts induced by weak coherent pulses that contain one or less than one photon per pulse on average. In spite of its tininess, the phase shift was measurable using much (~10^6 times) stronger coherent probe pulses than the pump pulses. We discuss the feasibility of quantum information processing using optical fibers, taking into...

  11. Sub-Shot-Noise Transmission Measurement Enabled by Active Feed-Forward of Heralded Single Photons

    Science.gov (United States)

    Sabines-Chesterking, J.; Whittaker, R.; Joshi, S. K.; Birchall, P. M.; Moreau, P. A.; McMillan, A.; Cable, H. V.; O'Brien, J. L.; Rarity, J. G.; Matthews, J. C. F.

    2017-07-01

    Harnessing the unique properties of quantum mechanics offers the possibility of delivering alternative technologies that can fundamentally outperform their classical counterparts. These technologies deliver advantages only when components operate with performance beyond specific thresholds. For optical quantum metrology, the biggest challenge that impacts on performance thresholds is optical loss. Here, we demonstrate how including an optical delay and an optical switch in a feed-forward configuration with a stable and efficient correlated photon-pair source reduces the detector efficiency required to enable quantum-enhanced sensing down to the detection level of single photons and without postselection. When the switch is active, we observe a factor of improvement in precision of 1.27 for transmission measurement on a per-input-photon basis compared to the performance of a laser emitting an ideal coherent state and measured with the same detection efficiency as our setup. When the switch is inoperative, we observe no quantum advantage.

  12. Waveguide integrated superconducting single-photon detectors with high internal quantum efficiency at telecom wavelengths.

    Science.gov (United States)

    Kahl, Oliver; Ferrari, Simone; Kovalyuk, Vadim; Goltsman, Gregory N; Korneev, Alexander; Pernice, Wolfram H P

    2015-06-10

    Superconducting nanowire single-photon detectors (SNSPDs) provide high efficiency for detecting individual photons while keeping dark counts and timing jitter minimal. Besides superior detection performance over a broad optical bandwidth, compatibility with an integrated optical platform is a crucial requirement for applications in emerging quantum photonic technologies. Here we present SNSPDs embedded in nanophotonic integrated circuits which achieve internal quantum efficiencies close to unity at 1550 nm wavelength. This allows for the SNSPDs to be operated at bias currents far below the critical current where unwanted dark count events reach milli-Hz levels while on-chip detection efficiencies above 70% are maintained. The measured dark count rates correspond to noise-equivalent powers in the 10(-19) W/Hz(-1/2) range and the timing jitter is as low as 35 ps. Our detectors are fully scalable and interface directly with waveguide-based optical platforms.

  13. Observing the average trajectories of single photons in a two-slit interferometer.

    Science.gov (United States)

    Kocsis, Sacha; Braverman, Boris; Ravets, Sylvain; Stevens, Martin J; Mirin, Richard P; Shalm, L Krister; Steinberg, Aephraim M

    2011-06-03

    A consequence of the quantum mechanical uncertainty principle is that one may not discuss the path or "trajectory" that a quantum particle takes, because any measurement of position irrevocably disturbs the momentum, and vice versa. Using weak measurements, however, it is possible to operationally define a set of trajectories for an ensemble of quantum particles. We sent single photons emitted by a quantum dot through a double-slit interferometer and reconstructed these trajectories by performing a weak measurement of the photon momentum, postselected according to the result of a strong measurement of photon position in a series of planes. The results provide an observationally grounded description of the propagation of subensembles of quantum particles in a two-slit interferometer.

  14. Manipulation of dynamic nuclear spin polarization in single quantum dots by photonic environment engineering

    Science.gov (United States)

    Fong, C. F.; Ota, Y.; Iwamoto, S.; Arakawa, Y.

    2017-06-01

    Optically induced dynamic nuclear spin polarization (DNP) in a semiconductor quantum dot (QD) requires many cycles of excitation of spin polarized carriers and carrier recombination. As such, the radiative lifetime of the exciton containing the electron becomes one of the limiting factors of DNP. In principle, changing the radiative lifetime of the exciton will affect DNP and thus the nuclear spin polarization. Here, we demonstrate the manipulation of DNP in single QDs through the engineering of the photonic environment using two-dimensional photonic crystals. We find that the achievable degree of nuclear spin polarization can be controlled through the modification of exciton radiative lifetime. Our results show the promise of achieving a higher degree of nuclear spin polarization via photonic environment engineering, with implications on spin-based quantum information processing.

  15. An ultra low noise telecom wavelength free running single photon detector using negative feedback avalanche diode.

    Science.gov (United States)

    Yan, Zhizhong; Hamel, Deny R; Heinrichs, Aimee K; Jiang, Xudong; Itzler, Mark A; Jennewein, Thomas

    2012-07-01

    It is challenging to implement genuine free running single-photon detectors for the 1550 nm wavelength range with simultaneously high detection efficiency (DE), low dark noise, and good time resolution. We report a novel read out system for the signals from a negative feedback avalanche diode (NFAD) [M. A. Itzler, X. Jiang, B. Nyman, and K. Slomkowski, "Quantum sensing and nanophotonic devices VI," Proc. SPIE 7222, 72221K (2009); X. Jiang, M. A. Itzler, K. ODonnell, M. Entwistle, and K. Slomkowski, "Advanced photon counting techniques V," Proc. SPIE 8033, 80330K (2011); M. A. Itzler, X. Jiang, B. M. Onat, and K. Slomkowski, "Quantum sensing and nanophotonic devices VII," Proc. SPIE 7608, 760829 (2010)], which allows useful operation of these devices at a temperature of 193 K and results in very low darkcounts (∼100 counts per second (CPS)), good time jitter (∼30 ps), and good DE (∼10%). We characterized two NFADs with a time-correlation method using photons generated from weak coherent pulses and photon pairs produced by spontaneous parametric down conversion. The inferred detector efficiencies for both types of photon sources agree with each other. The best noise equivalent power of the device is estimated to be 8.1 × 10(-18) W Hz(-1/2), more than 10 times better than typical InP/InGaAs single photon avalanche diodes (SPADs) show in free running mode. The afterpulsing probability was found to be less than 0.1% per ns at the optimized operating point. In addition, we studied the performance of an entanglement-based quantum key distribution (QKD) using these detectors and develop a model for the quantum bit error rate that incorporates the afterpulsing coefficients. We verified experimentally that using these NFADs it is feasible to implement QKD over 400 km of telecom fiber. Our NFAD photon detector system is very simple, and is well suited for single-photon applications where ultra-low noise and free-running operation is required, and some afterpulsing

  16. An ultra low noise telecom wavelength free running single photon detector using negative feedback avalanche diode

    Science.gov (United States)

    Yan, Zhizhong; Hamel, Deny R.; Heinrichs, Aimee K.; Jiang, Xudong; Itzler, Mark A.; Jennewein, Thomas

    2012-07-01

    It is challenging to implement genuine free running single-photon detectors for the 1550 nm wavelength range with simultaneously high detection efficiency (DE), low dark noise, and good time resolution. We report a novel read out system for the signals from a negative feedback avalanche diode (NFAD) [M. A. Itzler, X. Jiang, B. Nyman, and K. Slomkowski, "Quantum sensing and nanophotonic devices VI," Proc. SPIE 7222, 72221K (2009), 10.1117/12.814669; X. Jiang, M. A. Itzler, K. ODonnell, M. Entwistle, and K. Slomkowski, "Advanced photon counting techniques V," Proc. SPIE 8033, 80330K (2011), 10.1117/12.883543; M. A. Itzler, X. Jiang, B. M. Onat, and K. Slomkowski, "Quantum sensing and nanophotonic devices VII," Proc. SPIE 7608, 760829 (2010), 10.1117/12.843588], which allows useful operation of these devices at a temperature of 193 K and results in very low darkcounts (˜100 counts per second (CPS)), good time jitter (˜30 ps), and good DE (˜10%). We characterized two NFADs with a time-correlation method using photons generated from weak coherent pulses and photon pairs produced by spontaneous parametric down conversion. The inferred detector efficiencies for both types of photon sources agree with each other. The best noise equivalent power of the device is estimated to be 8.1 × 10-18 W Hz-1/2, more than 10 times better than typical InP/InGaAs single photon avalanche diodes (SPADs) show in free running mode. The afterpulsing probability was found to be less than 0.1% per ns at the optimized operating point. In addition, we studied the performance of an entanglement-based quantum key distribution (QKD) using these detectors and develop a model for the quantum bit error rate that incorporates the afterpulsing coefficients. We verified experimentally that using these NFADs it is feasible to implement QKD over 400 km of telecom fiber. Our NFAD photon detector system is very simple, and is well suited for single-photon applications where ultra-low noise and free

  17. Single-photon technique for the detection of periodic extraterrestrial laser pulses.

    Science.gov (United States)

    Leeb, W R; Poppe, A; Hammel, E; Alves, J; Brunner, M; Meingast, S

    2013-06-01

    To draw humankind's attention to its existence, an extraterrestrial civilization could well direct periodic laser pulses toward Earth. We developed a technique capable of detecting a quasi-periodic light signal with an average of less than one photon per pulse within a measurement time of a few tens of milliseconds in the presence of the radiation emitted by an exoplanet's host star. Each of the electronic events produced by one or more single-photon avalanche detectors is tagged with precise time-of-arrival information and stored. From this we compute a histogram displaying the frequency of event-time differences in classes with bin widths on the order of a nanosecond. The existence of periodic laser pulses manifests itself in histogram peaks regularly spaced at multiples of the-a priori unknown-pulse repetition frequency. With laser sources simulating both the pulse source and the background radiation, we tested a detection system in the laboratory at a wavelength of 850 nm. We present histograms obtained from various recorded data sequences with the number of photons per pulse, the background photons per pulse period, and the recording time as main parameters. We then simulated a periodic signal hypothetically generated on a planet orbiting a G2V-type star (distance to Earth 500 light-years) and show that the technique is capable of detecting the signal even if the received pulses carry as little as one photon on average on top of the star's background light.

  18. Quantum detector tomography of a time-multiplexed superconducting nanowire single-photon detector at telecom wavelengths.

    Science.gov (United States)

    Natarajan, Chandra M; Zhang, Lijian; Coldenstrodt-Ronge, Hendrik; Donati, Gaia; Dorenbos, Sander N; Zwiller, Val; Walmsley, Ian A; Hadfield, Robert H

    2013-01-14

    Superconducting nanowire single-photon detectors (SNSPDs) are widely used in telecom wavelength optical quantum information science applications. Quantum detector tomography allows the positive-operator-valued measure (POVM) of a single-photon detector to be determined. We use an all-fiber telecom wavelength detector tomography test bed to measure detector characteristics with respect to photon flux and polarization, and hence determine the POVM. We study the SNSPD both as a binary detector and in an 8-bin, fiber based, Time-Multiplexed (TM) configuration at repetition rates up to 4 MHz. The corresponding POVMs provide an accurate picture of the photon number resolving capability of the TM-SNSPD.

  19. Real-Time Quadrature Measurement of a Single-Photon Wave Packet with Continuous Temporal-Mode Matching.

    Science.gov (United States)

    Ogawa, Hisashi; Ohdan, Hideaki; Miyata, Kazunori; Taguchi, Masahiro; Makino, Kenzo; Yonezawa, Hidehiro; Yoshikawa, Jun-Ichi; Furusawa, Akira

    2016-06-10

    Real-time controls based on quantum measurements are powerful tools for various quantum protocols. However, their experimental realization has been limited by mode mismatch between the temporal mode of quadrature measurement and that heralded by photon detection. Here, we demonstrate real-time quadrature measurement of a single-photon wave packet induced by photon detection by utilizing continuous temporal-mode matching between homodyne detection and an exponentially rising temporal mode. Single photons in exponentially rising modes are also expected to be useful resources for interactions with other quantum systems.

  20. Photon-counting single-molecule spectroscopy for studying conformational dynamics and macromolecular interactions

    Energy Technology Data Exchange (ETDEWEB)

    Laurence, Ted Alfred [Univ. of California, Berkeley, CA (United States)

    2002-01-01

    Single-molecule methods have the potential to provide information about conformational dynamics and molecular interactions that cannot be obtained by other methods. Removal of ensemble averaging provides several benefits, including the ability to detect heterogeneous populations and the ability to observe asynchronous reactions. Single-molecule diffusion methodologies using fluorescence resonance energy transfer (FRET) are developed to monitor conformational dynamics while minimizing perturbations introduced by interactions between molecules and surfaces. These methods are used to perform studies of the folding of Chymotrypsin Inhibitor 2, a small, single-domain protein, and of single-stranded DNA (ssDNA) homopolymers. Confocal microscopy is used in combination with sensitive detectors to detect bursts of photons from fluorescently labeled biomolecules as they diffuse through the focal volume. These bursts are analyzed to extract fluorescence resonance energy transfer (FRET) efficiency. Advances in data acquisition and analysis techniques that are providing a more complete picture of the accessible molecular information are discussed. Photon Arrival-time Interval Distribution (PAID) analysis is a new method for monitoring macromolecular interactions by fluorescence detection with simultaneous determination of coincidence, brightness, diffusion time, and occupancy (proportional to concentration) of fluorescently-labeled molecules undergoing diffusion in a confocal detection volume. This method is based on recording the time of arrival of all detected photons, and then plotting the two-dimensional histogram of photon pairs, where one axis is the time interval between each pair of photons 1 and 2, and the second axis is the number of other photons detected in the time interval between photons 1 and 2. PAID is related to Fluorescence Correlation Spectroscopy (FCS) by a collapse of this histogram onto the time interval axis. PAID extends auto- and cross-correlation FCS

  1. Single photon detection and localization accuracy with an ebCMOS camera

    Energy Technology Data Exchange (ETDEWEB)

    Cajgfinger, T. [CNRS/IN2P3, Institut de Physique Nucléaire de Lyon, Villeurbanne F-69622 (France); Dominjon, A., E-mail: agnes.dominjon@nao.ac.jp [Université de Lyon, Université de Lyon 1, Lyon 69003 France. (France); Barbier, R. [CNRS/IN2P3, Institut de Physique Nucléaire de Lyon, Villeurbanne F-69622 (France); Université de Lyon, Université de Lyon 1, Lyon 69003 France. (France)

    2015-07-01

    The CMOS sensor technologies evolve very fast and offer today very promising solutions to existing issues facing by imaging camera systems. CMOS sensors are very attractive for fast and sensitive imaging thanks to their low pixel noise (1e-) and their possibility of backside illumination. The ebCMOS group of IPNL has produced a camera system dedicated to Low Light Level detection and based on a 640 kPixels ebCMOS with its acquisition system. After reminding the principle of detection of an ebCMOS and the characteristics of our prototype, we confront our camera to other imaging systems. We compare the identification efficiency and the localization accuracy of a point source by four different photo-detection devices: the scientific CMOS (sCMOS), the Charge Coupled Device (CDD), the Electron Multiplying CCD (emCCD) and the Electron Bombarded CMOS (ebCMOS). Our ebCMOS camera is able to identify a single photon source in less than 10 ms with a localization accuracy better than 1 µm. We report as well efficiency measurement and the false positive identification of the ebCMOS camera by identifying more than hundreds of single photon sources in parallel. About 700 spots are identified with a detection efficiency higher than 90% and a false positive percentage lower than 5. With these measurements, we show that our target tracking algorithm can be implemented in real time at 500 frames per second under a photon flux of the order of 8000 photons per frame. These results demonstrate that the ebCMOS camera concept with its single photon detection and target tracking algorithm is one of the best devices for low light and fast applications such as bioluminescence imaging, quantum dots tracking or adaptive optics.

  2. Non-classical correlations between single photons and phonons from a mechanical oscillator

    Science.gov (United States)

    Riedinger, Ralf; Hong, Sungkun; Norte, Richard A.; Slater, Joshua A.; Shang, Juying; Krause, Alexander G.; Anant, Vikas; Aspelmeyer, Markus; Gröblacher, Simon

    2016-02-01

    Interfacing a single photon with another quantum system is a key capability in modern quantum information science. It allows quantum states of matter, such as spin states of atoms, atomic ensembles or solids, to be prepared and manipulated by photon counting and, in particular, to be distributed over long distances. Such light-matter interfaces have become crucial to fundamental tests of quantum physics and realizations of quantum networks. Here we report non-classical correlations between single photons and phonons—the quanta of mechanical motion—from a nanomechanical resonator. We implement a full quantum protocol involving initialization of the resonator in its quantum ground state of motion and subsequent generation and read-out of correlated photon-phonon pairs. The observed violation of a Cauchy-Schwarz inequality is clear evidence for the non-classical nature of the mechanical state generated. Our results demonstrate the availability of on-chip solid-state mechanical resonators as light-matter quantum interfaces. The performance we achieved will enable studies of macroscopic quantum phenomena as well as applications in quantum communication, as quantum memories and as quantum transducers.

  3. Absorption spectroscopy at the ultimate quantum limit from single-photon states

    Science.gov (United States)

    Whittaker, R.; Erven, C.; Neville, A.; Berry, M.; O'Brien, J. L.; Cable, H.; Matthews, J. C. F.

    2017-02-01

    Absorption spectroscopy is routinely used to characterise chemical and biological samples. For the state-of-the-art in laser absorption spectroscopy, precision is theoretically limited by shot-noise due to the fundamental Poisson-distribution of photon number in laser radiation. In practice, the shot-noise limit can only be achieved when all other sources of noise are eliminated. Here, we use wavelength-correlated and tuneable photon pairs to demonstrate how absorption spectroscopy can be performed with precision beyond the shot-noise limit and near the ultimate quantum limit by using the optimal probe for absorption measurement—single photons. We present a practically realisable scheme, which we characterise both the precision and accuracy of by measuring the response of a control feature. We demonstrate that the technique can successfully probe liquid samples and using two spectrally similar types of haemoglobin we show that obtaining a given precision in resolution requires fewer heralded single probe photons compared to using an idealised laser.

  4. Two-way QKD with single-photon-added coherent states

    Science.gov (United States)

    Miranda, Mario; Mundarain, Douglas

    2017-12-01

    In this work we present a two-way quantum key distribution (QKD) scheme that uses single-photon-added coherent states and displacement operations. The first party randomly sends coherent states (CS) or single-photon-added coherent states (SPACS) to the second party. The latter sends back the same state it received. Both parties decide which kind of states they are receiving by detecting or not a photon on the received signal after displacement operations. The first party must determine whether its sent and received states are equal; otherwise, the case must be discarded. We are going to show that an eavesdropper provided with a beam splitter gets the same information in any of the non-discarded cases. The key can be obtained by assigning 0 to CS and 1 to SPACS in the non-discarded cases. This protocol guarantees keys' security in the presence of a beam splitter attack even for states with a high number of photons in the sent signal. It also works in a lossy quantum channel, becoming a good bet for improving long-distance QKD.

  5. Collective effects of nuclei in single X-ray photon superradiance

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Xiangjin

    2016-07-28

    This thesis is dedicated to the study of collective effects of nuclei in single X-ray photon superradiance. To this end we investigate aspects of superradiance in both nuclear forward scattering and in thin-film cavities with an embedded {sup 57}Fe nuclear layer. A general theoretical framework is developed to investigate a single-photon cooperative emission from a cloud of resonant systems, atoms or nuclei, in the presence of magnetic hyperfine splitting. In the limit of a thick sample, we present our results for two means to coherently control the collective single X-ray photon emission in nuclear forward scattering. In the limit of a thin sample in a thin-film cavity with embedded resonant nuclei, we find out that unlike the magnetic hyperfine splitting of a single atom or nucleus, interesting collective effects may occur which modify the hyperfine level structure. In addition, for a certain parameter regime a spectrum reminiscent of electromagnetically induced transparency (EIT) can be achieved. Based on this EIT-like effect, a theoretical control mechanism for stopping X-ray pulses in the thin-film X-ray cavity is put forward. Finally, we show theoretically that for the case of two nuclear ensembles in the thin-film cavity, pseudo-Rabi splitting due to the strong coupling between the two layers should occur. The latter findings are confirmed by preliminary experimental data.

  6. An aggregation-induced emission luminophore with multi-stimuli single- and two-photon fluorescence switching and large two-photon absorption cross section.

    Science.gov (United States)

    Xu, Bingjia; Xie, Mingyuan; He, Jiajun; Xu, Bin; Chi, Zhenguo; Tian, Wenjing; Jiang, Long; Zhao, Fuli; Liu, Siwei; Zhang, Yi; Xu, Zhizhan; Xu, Jiarui

    2013-01-11

    A novel aggregation- and crystallization-induced emission luminophore (ENPOMe) containing tetraphenylethene and acrylonitrile moieties with high fluorescence efficiency (Φ(F) of up to 0.85) has been easily synthesized. ENPOMe has an exceptionally large two-photon absorption cross section (σ) of 5548 GM, and exhibits striking multi-stimuli-responsive single- and two-photon fluorescence switching with excellent reversibility in the solid state.

  7. Spiral superconducting nanowire single-photon detector with efficiency over 50% at 1550 nm wavelength

    Science.gov (United States)

    Huang, J.; Zhang, W. J.; You, L. X.; Liu, X. Y.; Guo, Q.; Wang, Y.; Zhang, L.; Yang, X. Y.; Li, H.; Wang, Z.; Xie, X. M.

    2017-07-01

    Superconducting nanowire single-photon detectors (SNSPDs) are widely used for the detection of visible and near-infrared single photons. Due to the nature of the polarization sensitive absorption of the nanowire, the detection efficiency (DE) of the meander SNSPD is polarization sensitive. In order to obtain a polarization-insensitive device with high DE, we fabricated NbN SNSPDs with spiral structure, which were embedded into an optical cavity. No meaningful current crowding effect was observed in the spiral SNSPDs. The spiral SNSPD showed a maximal system detection efficiency of 52.5% at 1550 nm with a dark count rate of 100 Hz and a polarization extinction ratio of 1.04, due to the combination of a spiral geometry and an optical cavity.

  8. Stabilization of a long-armed fiber-optic single-photon interferometer.

    Science.gov (United States)

    Cho, Seok-Beom; Noh, Tae-Gon

    2009-10-12

    We report on single-photon interference experiments in a Michelson-type interferometer built with two 6-km-long fiber spools, as well as on the active stabilization of the interferometer. A weak coherent light signal was (de-) multiplexed with a strong reference light using wavelength-division multiplexing technique, and real-time feedback control technique was applied for the reference light to actively stabilize the phase fluctuation in the long-armed fiber interferometer. The stabilized interferometer showed phase stability of 0.06 rad, which corresponds to an optical path length fluctuation of 15 nm between the 6-km-long interfering arms. The raw visibility obtained without subtracting noise counts in the single-photon interference experiment was more than 98% for stabilized conditions.

  9. Ten years of biophotonics single-photon SPAD imager applications: retrospective and outlook

    Science.gov (United States)

    Bruschini, Claudio; Homulle, Harald; Charbon, Edoardo

    2017-02-01

    SPAD (single-photon avalanche diode) arrays are single-photon imagers that can provide unparalleled timeresolved sensing performance. Since their inception in standard CMOS technologies (2003), a host of architectures and target applications have been explored, ranging from simple pixel arrays, with off-chip data processing electronics, to fully integrated "smart" imagers with in-pixel time-stamping electronics and/or on-chip data processing fabric. Applications include (endoscopic) FLIM, (multi-beam multiphoton) FLIM-FRET, SPIMFCS, time-resolved Raman, NIROT, super-resolution microscopy, and PET, to name a few. We will review some representative sensors and applications, the corresponding challenges, and provide an outlook on the future of this fascinating technology

  10. Transverse single-spin asymmetries for direct photon and neutral pion production in midrapidity at PHENIX

    Science.gov (United States)

    Lewis, Nicole; Phenix Collaboration

    2017-09-01

    Large transverse single spin asymmetries for hadron production in proton-proton collisions were some of the first indicators of significant nonperturbative spin-momentum correlations in the proton. They have been found to persist up to collision energies of 510 GeV, yet their origin remains poorly understood. Measurements of different final-state particles in a wide variety of collision systems over a range of kinematics can help to identify and separate contributions from the proton versus hadronization, and from different parton flavors. Depending on the rapidity pion production can provide access to both initial- and final-state effects for a mix of parton flavors, while direct photons depend only on initial-state effects and are particularly sensitive to gluon dynamics in RHIC kinematics. The status of transverse single spin measurements for neutral pions and direct photons performed for p+p, p+Al, and p+Au collisions at PHENIX will be presented.

  11. Quantum dash based single section mode locked lasers for photonic integrated circuits.

    Science.gov (United States)

    Joshi, Siddharth; Calò, Cosimo; Chimot, Nicolas; Radziunas, Mindaugas; Arkhipov, Rostislav; Barbet, Sophie; Accard, Alain; Ramdane, Abderrahim; Lelarge, Francois

    2014-05-05

    We present the first demonstration of an InAs/InP Quantum Dash based single-section frequency comb generator designed for use in photonic integrated circuits (PICs). The laser cavity is closed using a specifically designed Bragg reflector without compromising the mode-locking performance of the self pulsating laser. This enables the integration of single-section mode-locked laser in photonic integrated circuits as on-chip frequency comb generators. We also investigate the relations between cavity modes in such a device and demonstrate how the dispersion of the complex mode frequencies induced by the Bragg grating implies a violation of the equi-distance between the adjacent mode frequencies and, therefore, forbids the locking of the modes in a classical Bragg Device. Finally we integrate such a Bragg Mirror based laser with Semiconductor Optical Amplifier (SOA) to demonstrate the monolithic integration of QDash based low phase noise sources in PICs.

  12. Chromium single-photon emitters in diamond fabricated by ion implantation

    Science.gov (United States)

    Aharonovich, Igor; Castelletto, Stefania; Johnson, Brett C.; McCallum, Jeffrey C.; Simpson, David A.; Greentree, Andrew D.; Prawer, Steven

    2010-03-01

    Controlled fabrication and identification of bright single-photon emitters is at the heart of quantum optics. Here we demonstrate controlled engineering of a chromium bright single-photon source in bulk diamond by ion implantation. The Cr center has fully polarized emission with a zero-phonon line centered at 749 nm, full width at half maximum of 4 nm, an extremely short lifetime of ˜1ns , and a count rate of 0.5×106counts/s . By combining the polarization measurements and the vibronic spectra, a model of the center has been proposed consisting of one interstitial chromium atom with a transition dipole along one of the ⟨100⟩ directions.

  13. Single-photon Coulomb explosion of methanol using broad bandwidth ultrafast EUV pulses.

    Science.gov (United States)

    Luzon, Itamar; Jagtap, Krishna; Livshits, Ester; Lioubashevski, Oleg; Baer, Roi; Strasser, Daniel

    2017-05-31

    Single-photon Coulomb explosion of methanol is instigated using the broad bandwidth pulse achieved through high-order harmonics generation. Using 3D coincidence fragment imaging of one molecule at a time, the kinetic energy release (KER) and angular distributions of the products are measured in different Coulomb explosion (CE) channels. Two-body CE channels breaking either the C-O or the C-H bonds are described as well as a proton migration channel forming H2O(+), which is shown to exhibit higher KER. The results are compared to intense-field Coulomb explosion measurements in the literature. The interpretation of broad bandwidth single-photon CE data is discussed and supported by ab initio calculations of the predominant C-O bond breaking CE channel. We discuss the importance of these findings for achieving time resolved imaging of ultrafast dynamics.

  14. Fault tolerant filtering and fault detection for quantum systems driven by fields in single photon states

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Qing, E-mail: qing.gao.chance@gmail.com; Dong, Daoyi, E-mail: daoyidong@gmail.com; Petersen, Ian R., E-mail: i.r.petersen@gmai.com [School of Engineering and Information Technology, University of New South Wales, Canberra, ACT 2600 (Australia); Rabitz, Herschel, E-mail: hrabitz@princeton.edu [Department of Chemistry, Princeton University, Princeton, New Jersey 08544 (United States)

    2016-06-15

    The purpose of this paper is to solve the fault tolerant filtering and fault detection problem for a class of open quantum systems driven by a continuous-mode bosonic input field in single photon states when the systems are subject to stochastic faults. Optimal estimates of both the system observables and the fault process are simultaneously calculated and characterized by a set of coupled recursive quantum stochastic differential equations.

  15. PET and Single-Photon Emission Computed Tomography in Brain Concussion.

    Science.gov (United States)

    Raji, Cyrus A; Henderson, Theodore A

    2018-02-01

    This article offers an overview of the application of PET and single photon emission computed tomography brain imaging to concussion, a type of mild traumatic brain injury and traumatic brain injury, in general. The article reviews the application of these neuronuclear imaging modalities in cross-sectional and longitudinal studies. Additionally, this article frames the current literature with an overview of the basic physics and radiation exposure risks of each modality. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Single photon emission computed tomography using perfusion tracers in seizure disorders.

    Science.gov (United States)

    Dierckx, R A; Vandevivere, J; Dom, L; Melis, K; Janssens, G; Dobbeleir, A; De Deyn, P P

    1992-07-01

    Single photon emission computed tomography (SPECT) using perfusion tracers makes it possible to estimate regional cerebral blood flow (rCBF) and, indirectly, local brain metabolism. It may be possible to detect and follow physiopathological alterations, such as may be seen in seizure disorders. The authors review the principles of and some data on perfusion SPECT in seizure disorders, stress advantages as well as major drawbacks and add their initial experience with Tc-99m hexamethylpropyleneamine oxime (HMPAO) SPECT in febrile convulsions.

  17. Hot water epilepsy: Phenotype and single photon emission computed tomography observations

    OpenAIRE

    Mehul Patel; Parthasarathy Satishchandra; Hanumanthapura Aravinda; Bharath, Rose D.; Sanjib Sinha

    2014-01-01

    We studied the anatomical correlates of reflex hot water epilepsy (HWE) using multimodality investigations viz. magnetic resonance imaging (MRI), electroencephalography (EEG), and single photon emission computed tomography (SPECT). Five men (mean age: 27.0 ΁ 5.8 years) with HWE were subjected to MRI of brain, video-EEG studies, and SPECT scan. These were correlated with phenotypic presentations. Seizures could be precipitated in three patients with pouring of hot water over the head and semio...

  18. Diagnostic merits of current and potential applications of single photon and positron imaging: a perspective

    Energy Technology Data Exchange (ETDEWEB)

    Harper, P. V.

    1978-01-01

    A brief review of the limitations of medical radionuclide imaging techniques in competition with x-ray CAT scanning and ultrasound suggest that the emphasis in this are should be on measurement of the physiologic uptake of tracer materials. Tomography greatly improves the possibilities of quantitation of this uptake - examples using positron and single photon techniques are presented for /sup 13/NH/sub 3/ and /sup 201/Tl in the heart.

  19. Design of diamond microcavities for single photon frequency down-conversion

    CERN Document Server

    Lin, Zin; Rodriguez, Alejandro W; Loncar, M

    2015-01-01

    We propose monolithic diamond cavities that can be used to convert color-center Fock-state single photons from emission wavelengths to telecommunication bands. We present a detailed theoretical description of the conversion process, analyzing important practical concerns such as nonlinear phase shifts and frequency mismatch. Our analysis predicts sustainable power requirements ($ \\lesssim 1~\\mathrm{W}$) for a chipscale nonlinear device with high conversion efficiencies.

  20. Monitoring CBF in clinical routine by dynamic single photon emission tomography (SPECT) of inhaled xenon-133

    DEFF Research Database (Denmark)

    Sugiyama, H; Christensen, J; Skyhøj Olsen, T

    1986-01-01

    A very simple and low-cost brain dedicated, rapidly rotating Single Photon Emission Tomograph SPECT is described. Its use in following patients with ischemic stroke is illustrated by two middle cerebral artery occlusion cases, one with persistent occlusion and low CBF in MCA territory, and one...... with early lysis of the occlusion having high CBF (massive luxury perfusion) for some weeks. Evidence of this kind may be essential in the evaluation of therapeutic measures in ischemic stroke....

  1. Realization of a Cascaded Quantum System: Heralded Absorption of a Single Photon Qubit by a Single-Electron Charged Quantum Dot.

    Science.gov (United States)

    Delteil, Aymeric; Sun, Zhe; Fält, Stefan; Imamoğlu, Atac

    2017-04-28

    Photonic losses pose a major limitation for the implementation of a quantum state transfer between nodes of a quantum network. A measurement that heralds a successful transfer without revealing any information about the qubit may alleviate this limitation. Here, we demonstrate the heralded absorption of a single photonic qubit, generated by a single neutral quantum dot, by a single-electron charged quantum dot that is located 5 m away. The transfer of quantum information to the spin degree of freedom takes place upon the emission of a photon; for a properly chosen or prepared quantum dot, the detection of this photon yields no information about the qubit. We show that this process can be combined with local operations optically performed on the destination node by measuring classical correlations between the absorbed photon color and the final state of the electron spin. Our work suggests alternative avenues for the realization of quantum information protocols based on cascaded quantum systems.

  2. Fast single-photon imager acquires 1024 pixels at 100 kframe/s

    Science.gov (United States)

    Guerrieri, Fabrizio; Tisa, Simone; Zappa, Franco

    2009-02-01

    We present the design and we discuss in depth the operating conditions of a two-dimensional (2-D) imaging array of single-photon detectors that provides a total of 1024 pixels, laid out in 32 rows by 32 columns array, integrated within a monolithic silicon chip with dimensions of 3.5 mm x 3.5 mm. We employed a standard high-voltage 0.35μm CMOS fabrication technology, with no need of any custom processing. Each pixel consists of one Single-Photon Avalanche Diode (SPAD) and a compact front-end analog electronics followed by a digital processing circuitry. The in-pixel front-end electronics senses the ignition of the avalanche, quenches the detector, provides a pulse and restores the detector for detecting a subsequent photon. The processing circuitry counts events (both photon and unwelcome "noise" ignition) within user-selectable integration time-slots and stores the count into an in-pixel memory cell, which is read-out in 10 ns/pixel. Such a two-levels pipeline architecture allows to acquire the actual frame while contemporary reading out the previous one, thus achieving a very high free-running frame rate, with negligible inter-frame dead-time. Each pixel is therefore a completely independent photon-counter. The measured Photo Detection Efficiency (PDE) tops 43% at 5V excess-bias, while the Dark-Counting Rate (DCR) is below 4kcps (counts per second) at room temperature. The maximum frame-rate depends on the system clock; with a convenient 100MHz system clock we achieved a free-running speed of 100 kframe/s from the all 1024 pixels.

  3. All-solid-state deep ultraviolet laser for single-photon ionization mass spectrometry.

    Science.gov (United States)

    Yuan, Chengqian; Liu, Xianhu; Zeng, Chenghui; Zhang, Hanyu; Jia, Meiye; Wu, Yishi; Luo, Zhixun; Fu, Hongbing; Yao, Jiannian

    2016-02-01

    We report here the development of a reflectron time-of-flight mass spectrometer utilizing single-photon ionization based on an all-solid-state deep ultraviolet (DUV) laser system. The DUV laser was achieved from the second harmonic generation using a novel nonlinear optical crystal KBe2BO3F2 under the condition of high-purity N2 purging. The unique property of this laser system (177.3-nm wavelength, 15.5-ps pulse duration, and small pulse energy at ∼15 μJ) bears a transient low power density but a high single-photon energy up to 7 eV, allowing for ionization of chemicals, especially organic compounds free of fragmentation. Taking this advantage, we have designed both pulsed nanospray and thermal evaporation sources to form supersonic expansion molecular beams for DUV single-photon ionization mass spectrometry (DUV-SPI-MS). Several aromatic amine compounds have been tested revealing the fragmentation-free performance of the DUV-SPI-MS instrument, enabling applications to identify chemicals from an unknown mixture.

  4. High-dimensional quantum key distribution with the entangled single-photon-added coherent state

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yang [Zhengzhou Information Science and Technology Institute, Zhengzhou, 450001 (China); Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Bao, Wan-Su, E-mail: 2010thzz@sina.com [Zhengzhou Information Science and Technology Institute, Zhengzhou, 450001 (China); Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Bao, Hai-Ze; Zhou, Chun; Jiang, Mu-Sheng; Li, Hong-Wei [Zhengzhou Information Science and Technology Institute, Zhengzhou, 450001 (China); Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2017-04-25

    High-dimensional quantum key distribution (HD-QKD) can generate more secure bits for one detection event so that it can achieve long distance key distribution with a high secret key capacity. In this Letter, we present a decoy state HD-QKD scheme with the entangled single-photon-added coherent state (ESPACS) source. We present two tight formulas to estimate the single-photon fraction of postselected events and Eve's Holevo information and derive lower bounds on the secret key capacity and the secret key rate of our protocol. We also present finite-key analysis for our protocol by using the Chernoff bound. Our numerical results show that our protocol using one decoy state can perform better than that of previous HD-QKD protocol with the spontaneous parametric down conversion (SPDC) using two decoy states. Moreover, when considering finite resources, the advantage is more obvious. - Highlights: • Implement the single-photon-added coherent state source into the high-dimensional quantum key distribution. • Enhance both the secret key capacity and the secret key rate compared with previous schemes. • Show an excellent performance in view of statistical fluctuations.

  5. Demonstration of Einstein-Podolsky-Rosen Steering Using Single-Photon Path Entanglement and Displacement-Based Detection.

    Science.gov (United States)

    Guerreiro, T; Monteiro, F; Martin, A; Brask, J B; Vértesi, T; Korzh, B; Caloz, M; Bussières, F; Verma, V B; Lita, A E; Mirin, R P; Nam, S W; Marsilli, F; Shaw, M D; Gisin, N; Brunner, N; Zbinden, H; Thew, R T

    2016-08-12

    We demonstrate the violation of an Einstein-Podolsky-Rosen steering inequality developed for single-photon path entanglement with displacement-based detection. We use a high-rate source of heralded single-photon path-entangled states, combined with high-efficiency superconducting-based detectors, in a scheme that is free of any postselection and thus immune to the detection loophole. This result conclusively demonstrates single-photon entanglement in a one-sided device-independent scenario, and opens the way towards implementations of device-independent quantum technologies within the paradigm of path entanglement.

  6. High-Dimensional Single-Photon Quantum Gates: Concepts and Experiments

    Science.gov (United States)

    Babazadeh, Amin; Erhard, Manuel; Wang, Feiran; Malik, Mehul; Nouroozi, Rahman; Krenn, Mario; Zeilinger, Anton

    2017-11-01

    Transformations on quantum states form a basic building block of every quantum information system. From photonic polarization to two-level atoms, complete sets of quantum gates for a variety of qubit systems are well known. For multilevel quantum systems beyond qubits, the situation is more challenging. The orbital angular momentum modes of photons comprise one such high-dimensional system for which generation and measurement techniques are well studied. However, arbitrary transformations for such quantum states are not known. Here we experimentally demonstrate a four-dimensional generalization of the Pauli X gate and all of its integer powers on single photons carrying orbital angular momentum. Together with the well-known Z gate, this forms the first complete set of high-dimensional quantum gates implemented experimentally. The concept of the X gate is based on independent access to quantum states with different parities and can thus be generalized to other photonic degrees of freedom and potentially also to other quantum systems.

  7. High-Dimensional Single-Photon Quantum Gates: Concepts and Experiments.

    Science.gov (United States)

    Babazadeh, Amin; Erhard, Manuel; Wang, Feiran; Malik, Mehul; Nouroozi, Rahman; Krenn, Mario; Zeilinger, Anton

    2017-11-03

    Transformations on quantum states form a basic building block of every quantum information system. From photonic polarization to two-level atoms, complete sets of quantum gates for a variety of qubit systems are well known. For multilevel quantum systems beyond qubits, the situation is more challenging. The orbital angular momentum modes of photons comprise one such high-dimensional system for which generation and measurement techniques are well studied. However, arbitrary transformations for such quantum states are not known. Here we experimentally demonstrate a four-dimensional generalization of the Pauli X gate and all of its integer powers on single photons carrying orbital angular momentum. Together with the well-known Z gate, this forms the first complete set of high-dimensional quantum gates implemented experimentally. The concept of the X gate is based on independent access to quantum states with different parities and can thus be generalized to other photonic degrees of freedom and potentially also to other quantum systems.

  8. Orthogonal sequencing multiplexer for superconducting nanowire single-photon detectors with RSFQ electronics readout circuit.

    Science.gov (United States)

    Hofherr, Matthias; Wetzstein, Olaf; Engert, Sonja; Ortlepp, Thomas; Berg, Benjamin; Ilin, Konstantin; Henrich, Dagmar; Stolz, Ronny; Toepfer, Hannes; Meyer, Hans-Georg; Siegel, Michael

    2012-12-17

    We propose an efficient multiplexing technique for superconducting nanowire single-photon detectors based on an orthogonal detector bias switching method enabling the extraction of the average count rate of a set of detectors by one readout line. We implemented a system prototype where the SNSPDs are connected to an integrated cryogenic readout and a pulse merger system based on rapid single flux quantum (RSFQ) electronics. We discuss the general scalability of this concept, analyze the environmental requirements which define the resolvability and the accuracy and demonstrate the feasibility of this approach with experimental results for a SNSPD array with four pixels.

  9. Superconducting nanowire single-photon detectors at a wavelength of 940 nm

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, W. J.; Li, H.; You, L. X., E-mail: lxyou@mail.sim.ac.cn; He, Y. H.; Zhang, L.; Liu, X.Y.; Yang, X. Y.; Wu, J. J.; Guo, Q.; Chen, S. J.; Wang, Z.; Xie, X. M. [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences (CAS), 865 Changning Rd., Shanghai 200050 (China)

    2015-06-15

    We develop single-photon detectors comprising single-mode fiber-coupled superconducting nanowires, with high system detection efficiencies at a wavelength of 940 nm. The detector comprises a 6.5-nm-thick, 110-nm-wide NbN nanowire meander fabricated onto a Si substrate with a distributed Bragg reflector for enhancing the optical absorptance. We demonstrate that, via the design of a low filling factor (1/3) and active area (Φ = 10 μm), the system reaches a detection efficiency of ∼60% with a dark count rate of 10 Hz, a recovery time <12 ns, and a timing jitter of ∼50 ps.

  10. General Implementation of All Possible POVMs of Single Photon Polarization States

    Science.gov (United States)

    Ahnert, S. E.; Payne, M. C.

    2004-11-01

    We propose here a single setup for the implementation of all possible positive operator value measurements (POVMs) of a single-photon polarization state. This includes POVMs with orthogonal projective, non-orthogonal projective, and non-projective sets of Kraus operators. Our setup is deterministic as opposed to probabilistic, which means that the setup delivers one of the possible POVM output states in every measurement. Furthermore our method does not require any ancillas except for vacuum states. Finally we illustrate how our setup can be used to implement two well-known POVMs, including one required for established quantum cryptography protocols [1, 2, 3, 4].

  11. DESIGN, PROTOTYPE AND MEASUREMENT OF A SINGLE-CELL DEFLECTING CAVITY FOR THE ADVANCED PHOTON SOURCE

    Energy Technology Data Exchange (ETDEWEB)

    Haipeng Wang, Guangfeng Cheng, Gianluigi Ciovati, Peter Kneisel, Robert Rimmer, Kai Tian, Larry Turlington, Alireza Nassiri, Geoff Waldschmidt

    2009-05-01

    After the design optimization of a squashed elliptical shape, single-cell, superconducting (SC) deflecting cavity at 2.815 GHz, a copper prototype has been bench measured to determine its rf properties and the effectiveness of waveguide damping of parasitic modes [1]. RF cold tests were also performed at 2K on niobium single-cell and two-cell prototype cavities. Details of impedance calculation using wakefiled analysis of the single-cell cavity are shown to meet the strict 200 mA beam stability requirement of the Advanced Photon Source (APS) at Argonne National Lab where a total of 16 single-cell cavities will be divided into two cryomodule. The design of higher-order mode (HOM) waveguide damping, the simulations of the Lorenz force detuning, and the prototype of on-cell damping are presented.

  12. Characterization of superconducting nanowire single-photon detector with artificial constrictions

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ling; Liu, Dengkuan; Wu, Junjie; He, Yuhao; Lv, Chaolin [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050 (China); Graduate University of the Chinese Academy of Sciences, Beijing 100049 (China); You, Lixing, E-mail: lxyou@mail.sim.ac.cn; Zhang, Weijun; Zhang, Lu; Liu, Xiaoyu; Wang, Zhen, E-mail: zwang@mail.sim.ac.cn; Xie, Xiaoming [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050 (China)

    2014-06-15

    Statistical studies on the performance of different superconducting nanowire single-photon detectors (SNSPDs) on one chip suggested that random constrictions existed in the nanowire that were barely registered by scanning electron microscopy. With the aid of advanced e-beam lithography, artificial geometric constrictions were fabricated on SNSPDs as well as single nanowires. In this way, we studied the influence of artificial constrictions on SNSPDs in a straight forward manner. By introducing artificial constrictions with different wire widths in single nanowires, we concluded that the dark counts of SNSPDs originate from a single constriction. Further introducing artificial constrictions in SNSPDs, we studied the relationship between detection efficiency and kinetic inductance and the bias current, confirming the hypothesis that constrictions exist in SNSPDs.

  13. Quantum-Dot Single-Photon Sources for Entanglement Enhanced Interferometry.

    Science.gov (United States)

    Müller, M; Vural, H; Schneider, C; Rastelli, A; Schmidt, O G; Höfling, S; Michler, P

    2017-06-23

    Multiphoton entangled states such as "N00N states" have attracted a lot of attention because of their possible application in high-precision, quantum enhanced phase determination. So far, N00N states have been generated in spontaneous parametric down-conversion processes and by mixing quantum and classical light on a beam splitter. Here, in contrast, we demonstrate superresolving phase measurements based on two-photon N00N states generated by quantum dot single-photon sources making use of the Hong-Ou-Mandel effect on a beam splitter. By means of pulsed resonance fluorescence of a charged exciton state, we achieve, in postselection, a quantum enhanced improvement of the precision in phase uncertainty, higher than prescribed by the standard quantum limit. An analytical description of the measurement scheme is provided, reflecting requirements, capability, and restraints of single-photon emitters in optical quantum metrology. Our results point toward the realization of a real-world quantum sensor in the near future.

  14. Decoherence-protected storage of a photonic polarization qubit in a single atom

    Science.gov (United States)

    Koerber, Matthias; Morin, Olivier; Langenfeld, Stefan; Neuzner, Andreas; Ritter, Stephan; Rempe, Gerhard

    2017-04-01

    The ability to faithfully store quantum information is a key requirements for many quantum technologies. Here, we present a quantum memory based on a single 87Rb atom in a high-finesse optical resonator, capable of storing and retrieving single-photon polarization qubits with an overall efficiency of 18% when probed with coherent laser pulses containing one photon on average. Initially the polarization of the photon is mapped onto the atom via a stimulated Raman adiabatic passage (STIRAP). Because the two atomic levels used to encode the qubit shift in opposite directions in the presence of a magnetic field the memory is susceptible to magnetic field fluctuations. This limits the coherence time to a few hundred microseconds. Using an optical Raman transfer we temporarily map the qubit to a protected subspace, thereby extending the coherence time to tens of milliseconds. It can be further increased to more than 100 milliseconds by means of a spin-echo technique. Our results are an important milestone towards the implementation of a quantum repeater allowing for long-distance quantum communication.

  15. Fast single photon avalanche photodiode-based time-resolved diffuse optical tomography scanner

    Science.gov (United States)

    Mu, Ying; Niedre, Mark

    2015-01-01

    Resolution in diffuse optical tomography (DOT) is a persistent problem and is primarily limited by high degree of light scatter in biological tissue. We showed previously that the reduction in photon scatter between a source and detector pair at early time points following a laser pulse in time-resolved DOT is highly dependent on the temporal response of the instrument. To this end, we developed a new single-photon avalanche photodiode (SPAD) based time-resolved DOT scanner. This instrument uses an array of fast SPADs, a femto-second Titanium Sapphire laser and single photon counting electronics. In combination, the overall instrument temporal impulse response function width was 59 ps. In this paper, we report the design of this instrument and validate its operation in symmetrical and irregularly shaped optical phantoms of approximately small animal size. We were able to accurately reconstruct the size and position of up to 4 absorbing inclusions, with increasing image quality at earlier time windows. We attribute these results primarily to the rapid response time of our instrument. These data illustrate the potential utility of fast SPAD detectors in time-resolved DOT. PMID:26417526

  16. Identification of Intensity Ratio Break Points from Photon Arrival Trajectories in Ratiometric Single Molecule Spectroscopy

    Science.gov (United States)

    Bingemann, Dieter; Allen, Rachel M.

    2012-01-01

    We describe a statistical method to analyze dual-channel photon arrival trajectories from single molecule spectroscopy model-free to identify break points in the intensity ratio. Photons are binned with a short bin size to calculate the logarithm of the intensity ratio for each bin. Stochastic photon counting noise leads to a near-normal distribution of this logarithm and the standard student t-test is used to find statistically significant changes in this quantity. In stochastic simulations we determine the significance threshold for the t-test’s p-value at a given level of confidence. We test the method’s sensitivity and accuracy indicating that the analysis reliably locates break points with significant changes in the intensity ratio with little or no error in realistic trajectories with large numbers of small change points, while still identifying a large fraction of the frequent break points with small intensity changes. Based on these results we present an approach to estimate confidence intervals for the identified break point locations and recommend a bin size to choose for the analysis. The method proves powerful and reliable in the analysis of simulated and actual data of single molecule reorientation in a glassy matrix. PMID:22837704

  17. Single-photon signals at CERN LEP in supersymmetric models with a light gravitino

    CERN Document Server

    López, J; Zichichi, Antonino

    1997-01-01

    We study the single-photon signals expected at LEP in models with a very light gravitino. The dominant process is neutralino-gravitino production (e+e- -> chi+ G) with subsequent neutralino decay via chi->gamma+G, giving a gamma+E_miss signal. We first calculate the cross section at arbitrary center-of-mass energies and provide new analytic expressions for the differential cross section valid for general neutralino compositions. We then consider the constraints on the gravitino mass from LEP 1 and LEP161 single-photon searches, and possible such searches at the Tevatron. We show that it is possible to evade the stringent LEP 1 limits and still obtain an observable rate at LEP 2, in particular in the region of parameter space that may explain the CDF e+e+gamma+gamma+E_T,miss event. As diphoton events from neutralino pair-production would not be kinematically accessible in this scenario, the observation of whichever photonic signal will discriminate among the various light-gravitino scenarios in the literature....

  18. A Miniaturized Linear Wire Ion Trap with Electron Ionization and Single Photon Ionization Sources

    Science.gov (United States)

    Wu, Qinghao; Tian, Yuan; Li, Ailin; Andrews, Derek; Hawkins, Aaron R.; Austin, Daniel E.

    2017-05-01

    A linear wire ion trap (LWIT) with both electron ionization (EI) and single photon ionization (SPI) sources was built. The SPI was provided by a vacuum ultraviolet (VUV) lamp with the ability to softly ionize organic compounds. The VUV lamp was driven by a pulse amplifier, which was controlled by a pulse generator, to avoid the detection of photons during ion detection. Sample gas was introduced through a leak valve, and the pressure in the system is shown to affect the signal-to-noise ratio and resolving power. Under optimized conditions, the limit of detection (LOD) for benzene was 80 ppbv using SPI, better than the LOD using EI (137 ppbv). System performance was demonstrated by distinguishing compounds in different classes from gasoline.

  19. Single pulse two photon fluorescence lifetime imaging (SP-FLIM) with MHz pixel rate.

    Science.gov (United States)

    Eibl, Matthias; Karpf, Sebastian; Weng, Daniel; Hakert, Hubertus; Pfeiffer, Tom; Kolb, Jan Philip; Huber, Robert

    2017-07-01

    Two-photon-excited fluorescence lifetime imaging microscopy (FLIM) is a chemically specific 3-D sensing modality providing valuable information about the microstructure, composition and function of a sample. However, a more widespread application of this technique is hindered by the need for a sophisticated ultra-short pulse laser source and by speed limitations of current FLIM detection systems. To overcome these limitations, we combined a robust sub-nanosecond fiber laser as the excitation source with high analog bandwidth detection. Due to the long pulse length in our configuration, more fluorescence photons are generated per pulse, which allows us to derive the lifetime with a single excitation pulse only. In this paper, we show high quality FLIM images acquired at a pixel rate of 1 MHz. This approach is a promising candidate for an easy-to-use and benchtop FLIM system to make this technique available to a wider research community.

  20. Scalable multiplexed detector system for high-rate telecom-band single-photon detection.

    Science.gov (United States)

    Brida, G; Degiovanni, I P; Piacentini, F; Schettini, V; Polyakov, S V; Migdall, A

    2009-11-01

    We present an actively multiplexed photon-counting detection system at telecom wavelengths that overcomes the difficulties of photon-counting at high rates. We find that for gated detectors, the heretofore unconsidered deadtime associated with the detector gate is a critical parameter, that limits the overall scalability of the scheme to just a few detectors. We propose and implement a new scheme that overcomes this problem and restores full scalability that allows an order of magnitude improvement with systems with as few as 4 detectors. When using just two multiplexed detectors, our experimental results show a 5x improvement over a single detector and a greater than 2x improvement over multiplexed schemes that do not consider gate deadtime.