WorldWideScience

Sample records for adenosine single photon

  1. Evaluation of coronary artery disease using myocardial thallium-201 imaging with single photon emission computed tomography during adenosine induced coronary vasodilation

    Energy Technology Data Exchange (ETDEWEB)

    Abe, Shinya; Takeishi, Yasuchika; Chiba, Junya; Tonooka, Ichiro; Tomoike, Hitonobu (Yamagata Univ. (Japan). School of Medicine)

    1993-02-01

    Adenosine-loaded Tl-201 myocardial SPECT was performed in consecutive 55 patients with suspected ischemic heart disease. Among these patients, 22 had cuncurrently exercise Tl-201 myocardial SPECT imaging for comparison. Adenosine was intravenously injected at a dose of 0.14 mg/kg/min continuously for 6 min, and 3 min after the stard of injection Tl-201 was injected via the different vein. Myocardial SPECT images were acquired at 5 min and 3 hr after the completion of intravenous injection of adenosine. Perfusion defect and the presence or absence of redistribution (RD) were visually interpreted from the short- and long-axial tomograms. Relative Tl-201 regional uptake ratios were quantitatively determined. Decreased systolic arterial pressure, increased heart rate, and slightly increased rate-pressure product were observed with adenosine injection. Chest pain (13 patients), head-ache (7), ST depression (17), and A-V block II were also seen; however, these symptoms rapidly disappeared with the withdrawal of adenosine. The findings by adenosine loading were concordent with those by exercise loading (91% for perfusion defect and 86% for presence or absence of RD). According to segments, both loading tests were concordent in 90% for persusion and 89% for RD. Both adenosine- and exercise-loaded imagings correlated well with regional Tl uptake by segements, the lowest value of Tl-201 defect, and extent score of Tl-201 defect. Adenosine-loaded imaging had a sensitivity of 100%, a specificity of 88%, and an accuracy of 97% for detecting parenchymal coronary lesions in evaluable 39 patients. In evaluable 22 patients, the sensitivity, specificity, and accuracy were 100%, 83%, and 95% for adenosine-loaded imaging and 88%, 83%, and 86% for exercise-loaded imaging. Thus, adenosine-loaded Tl-201 myocardial SPECT may be a safety and useful method for diagnosing ischemic heart disease. (N.K.).

  2. 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 fluoresc

  3. 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...

  4. Single photon quantum cryptography

    CERN Document Server

    Beveratos, A; Gacoin, T; Villing, A; Poizat, J P; Grangier, P; Beveratos, Alexios; Brouri, Rosa; Gacoin, Thierry; Villing, Andre; Poizat, Jean-Philippe; Grangier, Philippe

    2002-01-01

    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 (NV) color center in a diamond nanocrystal. The quantum bit error rate is less that 4.6% and the secure bit rate is 9500 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.

  5. 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.

  6. 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.

  7. Single photons on demand

    Energy Technology Data Exchange (ETDEWEB)

    Grangier, P. [Institut d' Optique, Laboratoire Charles Fabry, Orsay (France)]. E-mail: philippe.grangier@iota.u-psud.fr; Abram, I. [Laboratoire de Photonique et Nanostructures, Route de Nozay, Marcoussis (France)]. E-mail: izo.abram@lpn.cnrs.fr

    2003-02-01

    Quantum cryptography and information processing are set to benefit from developments in novel light sources that can emit photons one by one. Quantum mechanics has gained a reputation for making counter-intuitive predictions. But we rarely get the chance to witness these effects directly because, being humans, we are simply too big. Take light, for example. The light sources that are familiar to us, such as those used in lighting and imaging or in CD and DVD players, are so huge that they emit billions and billions of photons. But what if there was a light source that emitted just one photon at a time? Over the past few years, new types of light source that are able to emit photons one by one have been emerging from laboratories around the world. Pulses of light composed of a single photon correspond to power flows in the femtowatt range - a million billion times less than that of a table lamp. The driving force behind the development of these single-photon sources is a range of novel applications that take advantage of the quantum nature of light. Quantum states of superposed and entangled photons could lead the way to guaranteed-secure communication, to information processing with unprecedented speed and efficiency, and to new schemes for quantum teleportation. (U.K.)

  8. Simulating single photons with realistic photon sources

    Science.gov (United States)

    Yuan, Xiao; Zhang, Zhen; Lütkenhaus, Norbert; Ma, Xiongfeng

    2016-12-01

    Quantum information processing provides remarkable advantages over its classical counterpart. Quantum optical systems have been proved to be sufficient for realizing general quantum tasks, which, however, often rely on single-photon sources. In practice, imperfect single-photon sources, such as a weak-coherent-state source, are used instead, which will inevitably limit the power in demonstrating quantum effects. For instance, with imperfect photon sources, the key rate of the Bennett-Brassard 1984 (BB84) quantum key distribution protocol will be very low, which fortunately can be resolved by utilizing the decoy-state method. As a generalization, we investigate an efficient way to simulate single photons with imperfect ones to an arbitrary desired accuracy when the number of photonic inputs is small. Based on this simulator, we can thus replace the tasks that involve only a few single-photon inputs with the ones that make use of only imperfect photon sources. In addition, our method also provides a quantum simulator to quantum computation based on quantum optics. In the main context, we take a phase-randomized coherent state as an example for analysis. A general photon source applies similarly and may provide some further advantages for certain tasks.

  9. Interfacing single photons and single quantum dots with photonic nanostructures

    CERN Document Server

    Lodahl, Peter; Stobbe, Søren

    2013-01-01

    Photonic nanostructures provide a way of tailoring the interaction between light and matter and the past decade has witnessed a tremendous experimental and theoretical progress on this subject. In particular, the combination with semiconductor quantum dots has proven very successful. This manuscript reviews quantum optics with excitons in single quantum dots embedded in photonic nanostructures. The ability to engineer the interaction strength in integrated photonic nanostructures enables a range of fundamental quantum-electrodynamics experiments on, e.g., spontaneous-emission control, modified Lamb shifts, and enhanced dipole-dipole interaction. Furthermore, highly efficient single-photon sources and giant photon nonlinearities may be constructed with immediate applications for photonic quantum-information processing. The review summarizes the general theoretical framework of photon emission including the role of dephasing processes, and applies it to photonic nanostructures of current interest, such as photo...

  10. Nanodiamond Emitters of Single Photons

    Directory of Open Access Journals (Sweden)

    Vlasov I.I.

    2015-01-01

    Full Text Available Luminescence properties of single color centers were studied in nanodiamonds of different origin. It was found that single photon emitters could be realized even in molecularsized diamond (less than 2 nm capable of housing stable luminescent center “silicon-vacancy.” First results on incorporation of single-photon emitters based on luminescent nanodiamonds in plasmonic nanoantennas to enhance the photon count rate and directionality, diminish the fluorescence decay time, and provide polarization selectivity are presented.

  11. Hologram of a single photon

    Science.gov (United States)

    Chrapkiewicz, Radosław; Jachura, Michał; Banaszek, Konrad; Wasilewski, Wojciech

    2016-09-01

    The spatial structure of single photons is becoming an extensively explored resource to facilitate free-space quantum communication and quantum computation as well as for benchmarking the limits of quantum entanglement generation with orbital angular momentum modes or reduction of the photon free-space propagation speed. Although accurate tailoring of the spatial structure of photons is now routinely performed using methods employed for shaping classical optical beams, the reciprocal problem of retrieving the spatial phase-amplitude structure of an unknown single photon cannot be solved using complementary classical holography techniques that are known for excellent interferometric precision. Here, we introduce a method to record a hologram of a single photon that is probed by another reference photon, on the basis of a different concept of the quantum interference between two-photon probability amplitudes. As for classical holograms, the hologram of a single photon encodes the full information about the photon's ‘shape’ (that is, its quantum wavefunction) whose local amplitude and phase are retrieved in the demonstrated experiment.

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

    CERN Document Server

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

    2005-01-01

    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 on demand 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) (tau). 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.

  13. Spectral compression of single photons

    CERN Document Server

    Lavoie, Jonathan; Wright, Logan G; Fedrizzi, Alessandro; Resch, Kevin J

    2013-01-01

    Photons are critical to quantum technologies since they can be used for virtually all quantum information tasks: in quantum metrology, as the information carrier in photonic quantum computation, as a mediator in hybrid systems, and to establish long distance networks. The physical characteristics of photons in these applications differ drastically; spectral bandwidths span 12 orders of magnitude from 50 THz for quantum-optical coherence tomography to 50 Hz for certain quantum memories. Combining these technologies requires coherent interfaces that reversibly map centre frequencies and bandwidths of photons to avoid excessive loss. Here we demonstrate bandwidth compression of single photons by a factor 40 and tunability over a range 70 times that bandwidth via sum-frequency generation with chirped laser pulses. This constitutes a time-to-frequency interface for light capable of converting time-bin to colour entanglement and enables ultrafast timing measurements. It is a step toward arbitrary waveform generatio...

  14. Photon Statistics of Single-Photon Quantum States in Real Single Photon Detection

    Institute of Scientific and Technical Information of China (English)

    李刚; 李园; 王军民; 彭堃墀; 张天才

    2004-01-01

    @@ Single photon detection (SPD) with high quantum efficiency has been widely used for measurement of different quantum states with different photon distributions.Based on the direct single SPD and double-SPD of HBT configuration, we discuss the effect of a real SPD on the photon statistics measurement and it shows that the measured photon distributions for different quantum states are corrected in different forms.The results are confirmed by experiment with the strongly attenuated coherent light and thermal light.This system can be used to characterize the photon statistics of the fluorescence light from single atom or single molecular.

  15. Single-photon decision maker

    CERN Document Server

    Naruse, Makoto; Drezet, Aurelien; Huant, Serge; Aono, Masashi; Hori, Hirokazu; Kim, Song-Ju

    2015-01-01

    Decision making is critical in our daily lives and for society in general and is finding evermore practical applications in information and communication technologies. Herein, we demonstrate experimentally that single photons can be used to make decisions in uncertain, dynamically changing environments. Using a nitrogen-vacancy in a nanodiamond as a single-photon source, we demonstrate the decision-making capability by solving the multi-armed bandit problem. This capability is directly and immediately associated with single-photon detection in the proposed architecture, leading to adequate and adaptive autonomous decision making. This study makes it possible to create systems that benefit from the quantum nature of light to perform practical and vital intelligent functions.

  16. Ramsey Interference with Single Photons

    Science.gov (United States)

    Clemmen, Stéphane; Farsi, Alessandro; Ramelow, Sven; Gaeta, Alexander L.

    2016-11-01

    Interferometry using discrete energy levels of nuclear, atomic, or molecular systems is the foundation for a wide range of physical phenomena and enables powerful techniques such as nuclear magnetic resonance, electron spin resonance, Ramsey-based spectroscopy, and laser or maser technology. It also plays a unique role in quantum information processing as qubits may be implemented as energy superposition states of simple quantum systems. Here, we demonstrate quantum interference involving energy states of single quanta of light. In full analogy to the energy levels of atoms or nuclear spins, we implement a Ramsey interferometer with single photons. We experimentally generate energy superposition states of a single photon and manipulate them with unitary transformations to realize arbitrary projective measurements. Our approach opens the path for frequency-encoded photonic qubits in quantum information processing and quantum communication.

  17. Single photon and nonlocality

    Indian Academy of Sciences (India)

    Aurelien Drezet

    2007-03-01

    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.

  18. Detecting itinerant single microwave photons

    Science.gov (United States)

    Sathyamoorthy, Sankar Raman; Stace, Thomas M.; Johansson, Göran

    2016-08-01

    Single-photon detectors are fundamental tools of investigation in quantum optics and play a central role in measurement theory and quantum informatics. Photodetectors based on different technologies exist at optical frequencies and much effort is currently being spent on pushing their efficiencies to meet the demands coming from the quantum computing and quantum communication proposals. In the microwave regime, however, a single-photon detector has remained elusive, although several theoretical proposals have been put forth. In this article, we review these recent proposals, especially focusing on non-destructive detectors of propagating microwave photons. These detection schemes using superconducting artificial atoms can reach detection efficiencies of 90% with the existing technologies and are ripe for experimental investigations.

  19. 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.

  20. 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...

  1. The Single-Photon Router

    CERN Document Server

    Hoi, Io-Chun; Johansson, Göran; Palomaki, Tauno; Peropadre, Borja; Delsing, Per

    2011-01-01

    We have embedded an artificial atom, a superconducting "transmon" qubit, in an open transmission line and investigated the strong scattering of incident microwave photons ($\\sim6$ GHz). When an input coherent state, with an average photon number $N\\ll1$ is on resonance with the artificial atom, we observe extinction of up to 90% in the forward propagating field. We use two-tone spectroscopy to study scattering from excited states and we observe electromagnetically induced transparency (EIT). We then use EIT to make a single-photon router, where we can control to what output port an incoming signal is delivered. The maximum on-off ratio is around 90% with a rise and fall time on the order of nanoseconds, consistent with theoretical expectations. The router can easily be extended to have multiple output ports and it can be viewed as a rudimentary quantum node, an important step towards building quantum information networks.

  2. Photonic wires and trumpets for ultrabright single photon sources

    DEFF Research Database (Denmark)

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

    2013-01-01

    Photonic wires have recently demonstrated very attractive assets in the field of high-efficiency single photon sources. After presenting the basics of spontaneous emission control in photonic wires, we compare the two possible tapering strategies that can be applied to their output end so...... 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...... mirror and tapered tip display jointly a record-high efficiency (0.75±0.1 photon per pulse) and excellent single photon purity. Beyond single photon sources, photonic wires and trumpets appear as a very attractive resource for solid-state quantum optics experiments....

  3. Better Randomness with Single Photons

    CERN Document Server

    Oberreiter, Lukas

    2014-01-01

    Randomness is one of the most important resources in modern information science, since encryption founds upon the trust in random numbers. Since it is impossible to prove if an existing random bit string is truly random, it is relevant that they be generated in a trust worthy process. This requires specialized hardware for random numbers, for example a die or a tossed coin. But when all input parameters are known, their outcome might still be predicted. A quantum mechanical superposition allows for provably true random bit generation. In the past decade many quantum random number generators (QRNGs) were realized. A photonic implementation is described as a photon which impinges on a beam splitter, but such a protocol is rarely realized with non-classical light or anti-bunched single photons. Instead, laser sources or light emitting diodes are used. Here we analyze the difference in generating a true random bit string with a laser and with anti-bunched light. We show that a single photon source provides more r...

  4. 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.

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

    Science.gov (United States)

    Xiong, Chunle; Bell, Bryn; Eggleton, Benjamin J.

    2016-09-01

    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.

  6. Improved photon counting efficiency calibration using superconducting single photon detectors

    Science.gov (United States)

    Gan, Haiyong; Xu, Nan; Li, Jianwei; Sun, Ruoduan; Feng, Guojin; Wang, Yanfei; Ma, Chong; Lin, Yandong; Zhang, Labao; Kang, Lin; Chen, Jian; Wu, Peiheng

    2015-10-01

    The quantum efficiency of photon counters can be measured with standard uncertainty below 1% level using correlated photon pairs generated through spontaneous parametric down-conversion process. Normally a laser in UV, blue or green wavelength range with sufficient photon energy is applied to produce energy and momentum conserved photon pairs in two channels with desired wavelengths for calibration. One channel is used as the heralding trigger, and the other is used for the calibration of the detector under test. A superconducting nanowire single photon detector with advantages such as high photon counting speed (optical spectroscopy, super resolution microscopy, deep space observation, and so on.

  7. Highly efficient heralding of entangled single photons.

    Science.gov (United States)

    Ramelow, Sven; Mech, Alexandra; Giustina, Marissa; Gröblacher, Simon; Wieczorek, Witlef; Beyer, Jörn; Lita, Adriana; Calkins, Brice; Gerrits, Thomas; Nam, Sae Woo; Zeilinger, Anton; Ursin, Rupert

    2013-03-25

    Single photons are an important prerequisite for a broad spectrum of quantum optical applications. We experimentally demonstrate a heralded single-photon source based on spontaneous parametric down-conversion in collinear bulk optics, and fiber-coupled bolometric transition-edge sensors. Without correcting for background, losses, or detection inefficiencies, we measure an overall heralding efficiency of 83%. By violating a Bell inequality, we confirm the single-photon character and high-quality entanglement of our heralded single photons which, in combination with the high heralding efficiency, are a necessary ingredient for advanced quantum communication protocols such as one-sided device-independent quantum key distribution.

  8. Single-photon detection, truth, and misinterpretation

    Science.gov (United States)

    Berloffa, E. H.

    2013-10-01

    Within this investigation it is critically questioned, if we really can detect "single photons", respectively the response of a single quantum transition by use of modern photon detectors. In the course it is shown that avalanche photodiodes (AVDs) especially in the "Geiger" mode by virtue of its geometry (effective area) indeed can detect "single photon" events as proclaimed by the manufacturers, but they tacitly assume the bandwidth of originating visible source being not greater than ~ 2.107 [Hz]. A short excurse to solid state basic physics makes it obvious applying the adequate doping accomplishes "single photon detection". Nevertheless this does not mean there is a 1:1 correspondence between a photon emanated from the source location and that detected within the detector module. Propagation characteristics were simply overlooked during the numerous discussions about "single photon" detection. Practical examples are worked out on hand of a pin- / and a AVDphotodiode.

  9. 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.

  10. Hiding Single Photons With Spread Spectrum Technology

    CERN Document Server

    Belthangady, Chinmay; Yu, Ite A; Yin, G Y; Kahn, J M; Harris, S E

    2010-01-01

    We describe a proof-of-principal experiment demonstrating the use of spread spectrum technology at the single photon level. We show how single photons with a prescribed temporal shape, in the presence of interfering noise, may be hidden and recovered.

  11. Heralded single photon absorption by a single atom

    CERN Document Server

    Piro, Nicolas; Schuck, Carsten; Almendros, Marc; Huwer, Jan; Ghosh, Joyee; Haase, Albrecht; Hennrich, Markus; Dubin, Francois; Eschner, Jürgen

    2010-01-01

    The emission and absorption of single photons by single atomic particles is a fundamental limit of matter-light interaction, manifesting its quantum mechanical nature. At the same time, as a controlled process it is a key enabling tool for quantum technologies, such as quantum optical information technology [1, 2] and quantum metrology [3, 4, 5, 6]. Controlling both emission and absorption will allow implementing quantum networking scenarios [1, 7, 8, 9], where photonic communication of quantum information is interfaced with its local processing in atoms. In studies of single-photon emission, recent progress includes control of the shape, bandwidth, frequency, and polarization of single-photon sources [10, 11, 12, 13, 14, 15, 16, 17], and the demonstration of atom-photon entanglement [18, 19, 20]. Controlled absorption of a single photon by a single atom is much less investigated; proposals exist but only very preliminary steps have been taken experimentally such as detecting the attenuation and phase shift o...

  12. Single-photon source characterization with infrared-sensitive superconducting single-photon detectors

    CERN Document Server

    Hadfield, R H; Nam, S W; Stevens, M J; Hadfield, Robert H.; Mirin, Richard P.; Nam, Sae Woo; Stevens, Martin J.

    2006-01-01

    Single-photon sources and detectors are key enabling technologies in quantum information processing. Nanowire-based superconducting single-photon detectors (SSPDs) offer single-photon detection from the visible well into the infrared with low dark counts, low jitter and short dead times. We report on the high fidelity characterization (via antibunching and spontaneous emission lifetime measurements) of a cavity-coupled single-photon source at 902 nm using a pair of SSPDs. The twin SSPD scheme reported here is well-suited to the characterization of single-photon sources at telecom wavelengths (1310 nm, 1550 nm).

  13. Interfacing superconducting qubits and single optical photons

    CERN Document Server

    Das, Sumanta; Sørensen, Anders S

    2016-01-01

    We propose an efficient light-matter interface at optical frequencies between a superconducting qubit and a single photon. 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 far from the optical axis. We show that high fidelity, photon-mediated, entanglement between distant superconducting qubits can be achieved with incident pulses at the single photon level. Such low light level is highly sought for to overcome the decoherence of the superconducting qubit caused by absorption of optical photons.

  14. Stroing single-photons in microcavities arrays

    Science.gov (United States)

    Mirza, Imran M.; Enk, S. J. Van; Kimble, H. J.

    2014-03-01

    Coupling light to arrays of microcavities is one of the most promising avenues to store/delay classical light pulses [F. Krauss, Nat. Phot. 2, 448-450 (2008)]. However, from the perspective of benefiting quantum communication protocols, the same ideas in principle can be extended down to the single-photon (quantum) level as well. Particularly, for the purposes of entanglement purification and quantum repeaters a reliable storage of single photons is needed. We consider in our work [I. M. Mirza, S. Van Enk, H. Kimble JOSA B, 30,10 (2013)] cavities that are coupled through an optical fiber which is assumed to be forming a Markovian bath. For this study two powerful open quantum system techniques, Input-Output theory for cascaded quantum systems and the Quantum Trajectory approach are used in combination. For the confirmation of photon delays the Time-Dependent Spectrum of such a single photon is obtained. Interestingly this leads to a hole-burning effect showing that only certain frequency components in the single photon wavepackets are stored inside the cavities and hence are delayed in time. Since on-demand production of single photons is not an easy task we include in our description the actual generation of the single photon by assuming a single emitter in one the resonators.

  15. Photon-efficient imaging with a single-photon camera

    Science.gov (United States)

    Shin, Dongeek; Xu, Feihu; Venkatraman, Dheera; Lussana, Rudi; Villa, Federica; Zappa, Franco; Goyal, Vivek K.; Wong, Franco N. C.; Shapiro, Jeffrey H.

    2016-06-01

    Reconstructing a scene's 3D structure and reflectivity accurately with an active imaging system operating in low-light-level conditions has wide-ranging applications, spanning biological imaging to remote sensing. Here we propose and experimentally demonstrate a depth and reflectivity imaging system with a single-photon camera that generates high-quality images from ~1 detected signal photon per pixel. Previous achievements of similar photon efficiency have been with conventional raster-scanning data collection using single-pixel photon counters capable of ~10-ps time tagging. In contrast, our camera's detector array requires highly parallelized time-to-digital conversions with photon time-tagging accuracy limited to ~ns. Thus, we develop an array-specific algorithm that converts coarsely time-binned photon detections to highly accurate scene depth and reflectivity by exploiting both the transverse smoothness and longitudinal sparsity of natural scenes. By overcoming the coarse time resolution of the array, our framework uniquely achieves high photon efficiency in a relatively short acquisition time.

  16. Room temperature stable single-photon source

    CERN Document Server

    Beveratos, A; Brouri, R; Gacoin, T; Poizat, J P; Grangier, P; Beveratos, Alexios; Kuehn, Sergei; Brouri, Rosa; Gacoin, Thierry; Poizat, Jean-Philippe; Grangier, Philippe

    2001-01-01

    We report on the realization of a stable solid state room temperature source for single photons. It is based on the fluorescence of a single nitrogen-vacancy (NV) color center in a diamond nanocrystal. Antibunching has been observed in the fluorescence light under both continuous and pulsed excitation. Our source delivers 2*10^4 single-photon pulses per second at an excitation repetition rate of 10 MHz. The number of two-photon pulses is reduced by a factor of five compared to strongly attenuated coherent sources.

  17. Observation of Single-Photon Switching

    CERN Document Server

    Chen, Y F; Liu, Y C; Yu, I A; Chen, Yong-Fan; Tsai, Zen-Hsiang; Liu, Yu-Chen; Yu, Ite A.

    2005-01-01

    We report an experimental demonstration of single-photon switching in laser-cooled $^{87}$Rb atoms. A resonant probe pulse with an energy per unit area of one photon per $\\lambda^2/2\\pi$ propagates through the optically thick atoms. Its energy transmittance is greater than 63% or loss is less than $e^{-1}$ due to the effect of electromagnetically induced transparency. In the presence of a switching pulse with an energy per unit area of 1.4 photons per $\\lambda^2/2\\pi$, the energy transmittance of the same probe pulse becomes less than 37% or $e^{-1}$. This substantial reduction of the probe transmittance caused by single switching photons has potential applications in single-photon-level nonlinear optics and the manipulation of quantum information.

  18. Single photon sources with single semiconductor quantum dots

    Science.gov (United States)

    Shan, Guang-Cun; Yin, Zhang-Qi; Shek, Chan Hung; Huang, Wei

    2014-04-01

    In this contribution, we briefly recall the basic concepts of quantum optics and properties of semiconductor quantum dot (QD) which are necessary to the understanding of the physics of single-photon generation with single QDs. Firstly, we address the theory of quantum emitter-cavity system, the fluorescence and optical properties of semiconductor QDs, and the photon statistics as well as optical properties of the QDs. We then review the localization of single semiconductor QDs in quantum confined optical microcavity systems to achieve their overall optical properties and performances in terms of strong coupling regime, efficiency, directionality, and polarization control. Furthermore, we will discuss the recent progress on the fabrication of single photon sources, and various approaches for embedding single QDs into microcavities or photonic crystal nanocavities and show how to extend the wavelength range. We focus in particular on new generations of electrically driven QD single photon source leading to high repetition rates, strong coupling regime, and high collection efficiencies at elevated temperature operation. Besides, new developments of room temperature single photon emission in the strong coupling regime are reviewed. The generation of indistinguishable photons and remaining challenges for practical single-photon sources are also discussed.

  19. Superconducting nanowire single-photon imager

    CERN Document Server

    Zhao, Qing-Yuan; Calandri, Niccolò; Dane, Andrew E; McCaughan, Adam N; Bellei, Francesco; Wang, Hao-Zhu; Santavicca, Daniel F; Berggren, Karl K

    2016-01-01

    Detecting spatial and temporal information of individual photons is a crucial technology in today's quantum information science. Among the existing single-photon detectors, superconducting nanowire single-photon detectors (SNSPDs) have been demonstrated with a sub-50 ps timing jitter, near unity detection efficiency1, wide response spectrum from visible to infrared and ~10 ns reset time. However, to gain spatial sensitivity, multiple SNSPDs have to be integrated into an array, whose spatial and temporal resolutions are limited by the multiplexing circuit. Here, we add spatial sensitivity to a single nanowire while preserving the temporal resolution from an SNSPD, thereby turning an SNSPD into a superconducting nanowire single-photon imager (SNSPI). To achieve an SNSPI, we modify a nanowire's electrical behavior from a lumped inductor to a transmission line, where the signal velocity is slowed down to 0.02c (where c is the speed of light). Consequently, we are able to simultaneously read out the landing locati...

  20. Advantages of gated silicon single photon detectors

    CERN Document Server

    Lunghi, T; Barreiro, C; Stucki, D; Sanguinetti, B; Zbinden, H

    2012-01-01

    We present a gated silicon single photon detector based on a commercially available avalanche photodiode. Our detector achieves a photon detection efficiency of 45\\pm5% at 808 nm with 2x 10^-6 dark count per ns at -30V of excess bias and -30{\\deg}C. We compare gated and free-running detectors and show that this mode of operation has significant advantages in two representative experimental scenarios: detecting a single photon either hidden in faint continuous light or after a strong pulse. We also explore, at different temperatures and incident light intensities, the "charge persistence" effect, whereby a detector clicks some time after having been illuminated.

  1. 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.

  2. Photon statistics measurement by use of single photon detection

    Institute of Scientific and Technical Information of China (English)

    XIAO Liantuan; JIANG Yuqiang; ZHAO Yanting; YIN Wangbao; ZHAO Jianming; JIA Suotang

    2004-01-01

    The direct measurement of the Mandel para- meter of weak laser pulses, with 10 ns pulse duration time and the mean number of photon per pulsebeing approximately 0.1, is investigated by recording every photocount event. With the Hanbury Brown and Twiss detection scheme, and not more than one photon per pulse being detected during the sample time by single-photon counters, we have found that the single mode diode laser with driving current lower than the threshold yields a sub-Poissonian statistics. In addition, when the diode laser driving current is much higher than the threshold, it is validated that the Mandel parameter QC of the Poissonian coherent state is nearly The experimental results are in good agreement with theoretical prediction considering the measurement error.

  3. Solid-state single-photon emitters

    Science.gov (United States)

    Aharonovich, Igor; Englund, Dirk; Toth, Milos

    2016-10-01

    Single-photon emitters play an important role in many leading quantum technologies. There is still no 'ideal' on-demand single-photon emitter, but a plethora of promising material systems have been developed, and several have transitioned from proof-of-concept to engineering efforts with steadily improving performance. Here, we review recent progress in the race towards true single-photon emitters required for a range of quantum information processing applications. We focus on solid-state systems including quantum dots, defects in solids, two-dimensional hosts and carbon nanotubes, as these are well positioned to benefit from recent breakthroughs in nanofabrication and materials growth techniques. We consider the main challenges and key advantages of each platform, with a focus on scalable on-chip integration and fabrication of identical sources on photonic circuits.

  4. Measurement of Ultra-Short Single-Photon Pulse Duration with Two-Photon Interference

    Institute of Scientific and Technical Information of China (English)

    LV Fan; SUN Fang-Wen; ZOU Chang-Ling; HAN Zheng-Fu; GUO Guang-Can

    2011-01-01

    We proposed a protocol of measuring the duration of ultra-short single-photon pulse with two-photon interference.The pulse duration can be obtained from the width of the visibility of two-photon Hong-Ou-Mandel interference or the indistinguishability of the two photons. Moreover, the shape of a single-photon pulse can be measured with ultra-short single-photon pulses through the two-photon interference.%@@ We proposed a protocol of measuring the duration of ultra-short single-photon pulse with two-photon interference.The pulse duration can be obtained from the width of the visibility of two-photon Hong-Ou-Mandel interference or the indistinguishability of the two photons.Moreover, the shape of a single-photon pulse can be measured with ultra-short single-photon pulses through the two-photon interference.

  5. 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.

  6. 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...... be electrically driven. Several design strategies addressing these requirements have been proposed. In the cavity-based source, light emission is controlled using resonant cavity quantum electrodynamics effects, whereas in the waveguide-based source, broadband electric field screening effects are employed...... to direct the light emission into the optical mode of interest. For all the strategies, accurate modeling and careful optical engineering is required to achieve high performance....

  7. Experimental Quantum Cloning of Single Photons

    CERN Document Server

    Lamas-Linares, A; Howell, J C; Bouwmeester, D; Lamas-Linares, Antia; Simon, Christoph; Howell, John C.; Bouwmeester, Dik

    2002-01-01

    Although perfect copying of unknown quantum systems is forbidden by the laws of quantum mechanics, approximate cloning is possible. A natural way of realizing quantum cloning of photons is by stimulated emission. In this context the fundamental quantum limit to the quality of the clones is imposed by the unavoidable presence of spontaneous emission. In our experiment a single input photon stimulates the emission of additional photons from a source based on parametric down-conversion. This leads to the production of quantum clones with near optimal fidelity. We also demonstrate universality of the copying procedure by showing that the same fidelity is achieved for arbitrary input states.

  8. Single photon generation by pulsed excitation of a single dipole

    CERN Document Server

    Brouri, R; Poizat, J P; Grangier, P; Brouri, Rosa; Beveratos, Alexios; Poizat, Jean-Philippe; Grangier, Philippe

    2000-01-01

    The fluorescence of a single dipole excited by an intense light pulse can lead to the generation of another light pulse containing a single photon. The influence of the duration and energy of the excitation pulse on the number of photons in the fluorescence pulse is studied. The case of a two-level dipole with strongly damped coherences is considered. The presence of a metastable state leading to shelving is also investigated.

  9. Transmitting more than 10 bit with a single photon

    NARCIS (Netherlands)

    Tentrup, T.B.H.; Hummel, T.; Wolterink, T.A.W.; Uppu, R.; Mosk, A.P.; Pinkse, P.W.H.

    2016-01-01

    Encoding information in the position of single photons has no known limits, given infinite resources. Using a heralded single-photon source and a Spatial Light Modulator (SLM), we steer single photons to specific positions in a virtual grid on a large-area spatially resolving photon-counting detecto

  10. Single-photon indistinguishability: influence of phonons

    DEFF Research Database (Denmark)

    Nielsen, Per Kær; Lodahl, Peter; Jauho, Antti-Pekka

    2012-01-01

    effects is important in linear optical quantum computing [1], where a device emitting fully coherent indistinguishable single photons on demand, is the essential ingredient. In this contribution we present a numerically exact simulation of the effect of phonons on the degree of indistinguishability......Recent years have demonstrated that the interaction with phonons plays an important role in semiconductor based cavity QED systems [2], consisting of a quantum dot (QD) coupled to a single cavity mode [Fig. 1(a)], where the phonon interaction is the main decoherence mechanism. Avoiding decoherence...... of photons emitted from a solid-state cavity QED system. Our model rigorously describes non-Markovian effects to all orders in the phonon coupling constant, being based on an exact diagonalization procedure accounting for the time evoluiton of one-time and two-time photon correlation funcitons. We compare...

  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. Single photonics at telecom wavelengths using nanowire superconducting detectors

    CERN Document Server

    Zinoni, C; Fiore, A; Gerardino, A; Goltsman, G N; Li, L H; Lunghi, L; Marsili, F; Smirnov, K V; Vakhtomin, Y B; Vakhtomin, Yu. B.

    2006-01-01

    Single photonic applications - such as quantum key distribution - rely on the transmission of single photons, and require the ultimate sensitivity that an optical detector can achieve. Single-photon detectors must convert the energy of an optical pulse containing a single photon into a measurable electrical signal. We report on fiber-coupled superconducting single-photon detectors (SSPDs) with specifications that exceed those of avalanche photodiodes (APDs), operating at telecommunication wavelength, in sensitivity, temporal resolution and repetition frequency. The improved performance is demonstrated by measuring the intensity correlation function g(2)(t) of single-photon states at 1300nm produced by single semiconductor quantum dots (QDs).

  13. 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…

  14. Interfacing superconducting qubits and single optical photons

    NARCIS (Netherlands)

    Das, Sumanta; Faez, Sanli; Sørensen, Anders S.

    2016-01-01

    We propose an efficient light-matter interface at optical frequencies between a superconducting qubit and a single photon. 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

  15. Infrared Superconducting Single-Photon Detectors

    Science.gov (United States)

    2012-10-05

    group realized small microstrip devices, the next iteration of which may narrow the line width to below 100 nm, entering the single-photon detection...and will explore superconducting detectors with integrated waveguide circuits and novel deposition techniques. 15. SUBJECT...world record quantum cryptography demonstrations [9] and operation of quantum waveguide circuits at telecom wavelengths [10]. Beyond the quantum

  16. 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.

  17. Single-photon imaging in CMOS

    NARCIS (Netherlands)

    Charbon, E.

    2010-01-01

    We report on the architectural design and fabrication of medium and large arrays of single-photon avalanche diodes (SPADs) for a variety of applications in physics, medicine, and the life sciences. Due to dynamic nature of SPADs, designs featuring a large number of SPADs require careful analysis of

  18. Single carbon-nanotube photonics and optoelectronics

    Science.gov (United States)

    Kato, Yuichiro K.

    2015-03-01

    Single-walled carbon nanotubes have unique optical properties as a result of their one-dimensional structure. Not only do they exhibit strong polarization for both absorption and emission, large exciton binding energies allow for room-temperature excitonic luminescence. Furthermore, their emission is in the telecom-wavelengths and they can be directly synthesized on silicon substrates, providing new opportunities for nanoscale photonics and optoelectronics. Here we discuss the use of individual single-walled carbon nanotubes for generation, manipulation, and detection of light on a chip. Their emission properties can be controlled by coupling to silicon photonic structures such as photonic crystal microcavities and microdisk resonators. Simultaneous photoluminescence and photocurrent measurements show that excitons can dissociate spontaneously, enabling photodetection at low bias voltages despite the large binding energies. More recently, we have found that alternating gate-voltages can generate optical pulse trains from individual nanotubes. Ultimately, these results may be combined to achieve further control over photons at the nanoscale. Work supported by KAKENHI, The Canon Foundation, The Asahi Glass Foundation, and JSPS Open Partnership Joint Projects, as well as the Nanotechnology Platform and Photon Frontier Network Program of MEXT, Japan.

  19. High Polarization Single Mode Photonic Crystal Microlaser

    Institute of Scientific and Technical Information of China (English)

    CHEN Wei; XING Ming-Xin; ZHOU Wen-Jun; LIU An-Jin; ZHENG Wan-Hua

    2009-01-01

    Generally,dipole mode is a doubly degenerate mode.Theoretical calculations have indicated that the single dipole mode of two-dimensional photonic crystal single point defect cavity shows high polarization property.We present a structure with elongated lattice,which only supports a single y-dipole mode.With this structure we can eliminate the degeneracy,control the lasing action of the cavity and demonstrate the high polarization property of the single dipole mode.In our experiment,the polarization extinction ratio of the y-dipole mode is as high as 51:1.

  20. 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-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-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...

  1. Detecting single photons: a supramolecular matter?

    Science.gov (United States)

    Cangiano, Lorenzo; Dell'Orco, Daniele

    2013-01-04

    Rod photoreceptors detect single photons through a tradeoff of light collecting ability, amplification and speed. Key roles are played by rhodopsin (Rh) and transducin (G(t)), whose complex supramolecular organization in outer segment disks begs for a functional interpretation. Here we review past and recent evidence of a temperature-dependence of photon detection by mammalian rods, and link this phenomenon with the putative oligomeric organization of Rh and new ideas on the dynamics of Rh-G(t) interaction. Identifying an electrophysiological correlate of the supramolecular organization of Rh and G(t) may shed light on the evolutionary advantage it confers to night vision.

  2. Discriminating orthogonal single-photon images

    Science.gov (United States)

    Broadbent, Curtis J.; Zerom, Petros; Shin, Heedeuk; Howell, John C.; Boyd, Robert W.

    2009-03-01

    We can encode an image from an orthogonal basis set onto a single photon from a downconverted pair via the use of an amplitude mask. We can then discriminate the image imprinted on the photon from other images in the set using holographic-matched filtering techniques. We demonstrate this procedure experimentally for an image space of two objects, and we discuss the possibility of applying this method to a much larger image space. This process could have important implications for the manipulation of images at the quantum level.

  3. Purification of a single photon nonlinearity

    CERN Document Server

    Snijders, H; Norman, J; Bakker, M P; Gossard, A; Bowers, J E; van Exter, M P; Bouwmeester, D; Löffler, W

    2016-01-01

    We show that the lifetime-reduced fidelity of a semiconductor quantum dot-cavity single photon nonlinearity can be restored by polarization pre- and postselection. This is realized with a polarization degenerate microcavity in the weak coupling regime, where an output polarizer enables quantum interference of the two orthogonally polarized transmission amplitudes. This allows us to transform incident coherent light into a stream of strongly correlated photons with a second-order correlation function of g2(0)~40, larger than previous experimental results even in the strong-coupling regime. This purification technique might also be useful to improve the fidelity of quantum dot based logic gates.

  4. Single-Photon Detection at Telecom Wavelengths

    Institute of Scientific and Technical Information of China (English)

    SUN Zhi-Bin; MA Hai-Qiang; LEI Ming; WANG Di; LIU Zhao-Jie; YANG Han-Dong; WU Ling-An; ZHAI Guang-Jie; FENG Ji

    2007-01-01

    A single-photon detector based on an InGaAs avalanche photodiode has been developed for use at telecom wavelengths. A suitable delay and sampling gate modulation circuit are used to prevent positive and negative transient pulses from influencing the detection of true photon induced avalanches. A monostable trigger circuit eliminates the influence of avalanche peak jitter, and a dead time modulation feedback control circuit decreases the afterpulsing. From performance tests we find that at the optimum operation point, the quantum efficiency is 12% and the dark count rate 1.5 × 10-6 ns-1, with a detection rate of 500 kHz.

  5. An experimental demonstration of single photon nonlocality

    CERN Document Server

    Hessmo, B; Heydari, H; Björk, G; Hessmo, Bj\\"orn; Usachev, Pavel; Heydari, Hoshang; Bj\\"ork, Gunnar

    2003-01-01

    In this letter we experimentally implement a single photon Bell test based on the ideas of S. Tan et al. [Phys. Rev. Lett., vol. 66, 252 (1991)] and L. Hardy [Phys. Rev. Lett.,vol. 73, 2279 (1994)]. A double heterodyne measurement is used to measure correlations in the Fock space spanned by zero and one photons. Local oscillators used in the correlation measurement are distributed to two observers by co-propagating it in an orthogonal polarization mode. This method eliminates the need for interferometrical stability in the setup, consequently making it a robust and scalable method.

  6. Deterministic Single-Phonon Source Triggered by a Single Photon

    CERN Document Server

    Söllner, Immo; Lodahl, Peter

    2016-01-01

    We propose a scheme that enables the deterministic generation of single phonons at GHz frequencies triggered by single photons in the near infrared. This process is mediated by a quantum dot embedded on-chip in an opto-mechanical circuit, which allows for the simultaneous control of the relevant photonic and phononic frequencies. We devise new opto-mechanical circuit elements that constitute the necessary building blocks for the proposed scheme and are readily implementable within the current state-of-the-art of nano-fabrication. This will open new avenues for implementing quantum functionalities based on phonons as an on-chip quantum bus.

  7. Heralded single-photon ghost imaging

    CERN Document Server

    Aspden, Reuben S; Boyd, Robert W; Padgett, Miles J

    2013-01-01

    Correlated-photon imaging, popularly known as ghost imaging, is a technique whereby an image is formed from light that has never interacted with the object. In ghost imaging experiments two correlated light fields are produced. One of these fields illuminates the object, and the other field is measured by a spatially resolving detector. In the quantum regime these correlated light fields entail entangled photons produced by spontaneous parametric down-conversion. To date, all correlated-photon ghost-imaging experiments have scanned a single-pixel detector through the field of view to obtain the spatial information. However, scanning leads to a poor sampling efficiency, which becomes worse as the number of pixels N in the image is increased. In this work we overcome such limitations by using a time-gated camera to record the single-photon events across the full scene. We produce high-contrast images in either the image plane or far-field of the down-conversion source, taking advantage of the EPR-like correlati...

  8. Sub-megahertz linewidth single photon source

    Science.gov (United States)

    Rambach, Markus; Nikolova, Aleksandrina; Weinhold, Till J.; White, Andrew G.

    2016-12-01

    We report 100% duty cycle generation of sub-MHz single photon pairs at the rubidium D1 line using cavity-enhanced spontaneous parametric downconversion. The temporal intensity cross correlation function exhibits a bandwidth of 666 ±16 kHz for the single photons, an order of magnitude below the natural linewidth of the target transition. A half-wave plate inside our cavity helps to achieve triple resonance between pump, signal, and idler photon, reducing the bandwidth and simplifying the locking scheme. Additionally, stabilisation of the cavity to the pump frequency enables the 100% duty cycle. The quantum nature of the source is confirmed by the idler-triggered second-order autocorrelation function at τ =0 to be gs,s (2 )(0 ) = 0.016 ±0.002 for a heralding rate of 5 kHz. The generated photons are well-suited for storage in quantum memory schemes with sub-natural linewidths, such as gradient echo memories.

  9. Sub-megahertz linewidth single photon source

    Directory of Open Access Journals (Sweden)

    Markus Rambach

    2016-12-01

    Full Text Available We report 100% duty cycle generation of sub-MHz single photon pairs at the rubidium D1 line using cavity-enhanced spontaneous parametric downconversion. The temporal intensity cross correlation function exhibits a bandwidth of 666±16 kHz for the single photons, an order of magnitude below the natural linewidth of the target transition. A half-wave plate inside our cavity helps to achieve triple resonance between pump, signal, and idler photon, reducing the bandwidth and simplifying the locking scheme. Additionally, stabilisation of the cavity to the pump frequency enables the 100% duty cycle. The quantum nature of the source is confirmed by the idler-triggered second-order autocorrelation function at τ=0 to be gs,s(2(0= 0.016±0.002 for a heralding rate of 5 kHz. The generated photons are well-suited for storage in quantum memory schemes with sub-natural linewidths, such as gradient echo memories.

  10. T-shaped single-photon router.

    Science.gov (United States)

    Lu, Jing; Wang, Z H; Zhou, Lan

    2015-09-07

    We study the transport properties of a single photon scattered by a two-level system (TLS) in a T-shaped waveguide, which is made of two coupled-resonator waveguides (CRWs)- an infinite CRW and a semi-infinite CRW. The spontaneous emission of the TLS directs single photons from one CRW to the other. Although the transfer rate is different for the wave incident from different CRWs, due to the boundary breaking the translational symmetry, the boundary can enhance the transfer rate found in Phys. Rev. Lett. 111, 103604 (2013) and Phys. Rev. A 89, 013805 (2014), as the transfer rate could be unity for the wave incident from the semi-infinite CRW.

  11. Atomic metasurfaces for manipulation of single photons

    CERN Document Server

    Zhou, Ming; Kats, Mikhail; Yu, Zongfu

    2016-01-01

    Metasurfaces are an emerging platform for the manipulation of light on a two-dimensional plane. Existing metasurfaces comprise arrays of optical resonators such as plasmonic antennas or high-index nanoparticles. In this letter, we describe a new type of metasurface based on electronic transitions in two-level systems (TLSs). Specifically, we investigated a sheet of rubidium (Rb) atoms, whose energy levels can be tuned with structured illumination from a control laser, which enables dynamically tunable single-photon steering. These metasurface elements are lossless and orders of magnitude smaller than conventional optical resonators, which allows for the overlapping of multiple metasurfaces in a single plane, enabling multi-band operation. We demonstrate that atomic metasurfaces can be passive optical elements, and can also be utilized for beaming of spontaneously emitted photons. Though conceptually similar to conventional metasurfaces, the use of TLSs, which are inherently Fermionic, will lead to numerous ne...

  12. Advantages of gated silicon single photon detectors

    Science.gov (United States)

    Legré, Matthieu; Lunghi, Tommaso; Stucki, Damien; Zbinden, Hugo

    2013-05-01

    We present gated silicon single photon detectors based on two commercially available avalanche photodiodes (APDs) and one customised APD from ID Quantique SA. This customised APD is used in a commercially available device called id110. A brief comparison of the two commercial APDs is presented. Then, the charge persistence effect of all of those detectors that occurs just after a strong illumination is shown and discussed.

  13. Single photon emission based on coherent state preparation

    Science.gov (United States)

    Ester, P.; Lackmann, L.; Michaelis de Vasconcellos, S.; Hübner, M. C.; Zrenner, A.; Bichler, M.

    2007-09-01

    The authors report here on deterministic single photon emission after coherent optical state preparation in the p-shell of a single InGaAs /GaAs quantum dot. In the approach, they use p-shell Rabi flopping followed by relaxation to the s-shell ground state with subsequent spontaneous single photon emission. Pulsed photon correlation experiments show complete suppression of the correlation peak at zero time delay and hence demonstrate clean single photon emission.

  14. Photon pair source via two coupling single quantum emitters

    Institute of Scientific and Technical Information of China (English)

    彭勇刚; 郑雨军

    2015-01-01

    We study the two coupling two-level single molecules driven by an external field as a photon pair source. The proba-bility of emitting two photons, P2, is employed to describe the photon pair source quality in a short time, and the correlation coefficient RAB is employed to describe the photon pair source quality in a long time limit. The results demonstrate that the coupling single quantum emitters can be considered as a stable photon pair source.

  15. Indistinguishable single photons with real-time-programmable electronic triggering

    CERN Document Server

    Dada, Adetunmise C; Malein, Ralph N E; Koutroumanis, Antonios; Ma, Yong; Zajac, Joanna M; Lim, Ju Y; Song, Jin D; Gerardot, Brian D

    2016-01-01

    A key ingredient for quantum photonic technologies is an on-demand source of indistinguishable single photons. State-of-the-art indistinguishable-single-photon sources typically employ resonant excitation pulses with fixed repetition rates, creating a string of single photons with predetermined arrival times. However, in future applications, an independent electronic signal from a larger quantum circuit or network will trigger the generation of an indistinguishable photon. Further, operating the photon source up to the limit imposed by its lifetime is desirable. Here we report on the application of a true on-demand approach in which we can electronically trigger the precise arrival time of a single photon as well as control the excitation pulse duration. We investigate in detail the effect of finite duration of an excitation $\\pi$ pulse on the degree of photon antibunching. Finally, we demonstrate that highly indistinguishable single photons can be generated using this on-demand approach, enabling maximum fle...

  16. Purification of a single-photon nonlinearity

    Science.gov (United States)

    Snijders, H.; Frey, J. A.; Norman, J.; Bakker, M. P.; Langman, E. C.; Gossard, A.; Bowers, J. E.; van Exter, M. P.; Bouwmeester, D.; Löffler, W.

    2016-01-01

    Single photon nonlinearities based on a semiconductor quantum dot in an optical microcavity are a promising candidate for integrated optical quantum information processing nodes. In practice, however, the finite quantum dot lifetime and cavity-quantum dot coupling lead to reduced fidelity. Here we show that, with a nearly polarization degenerate microcavity in the weak coupling regime, polarization pre- and postselection can be used to restore high fidelity. The two orthogonally polarized transmission amplitudes interfere at the output polarizer; for special polarization angles, which depend only on the device cooperativity, this enables cancellation of light that did not interact with the quantum dot. With this, we can transform incident coherent light into a stream of strongly correlated photons with a second-order correlation value up to 40, larger than previous experimental results, even in the strong-coupling regime. This purification technique might also be useful to improve the fidelity of quantum dot based logic gates. PMID:27573361

  17. Calibrating photon counts from a single image

    CERN Document Server

    Heintzmann, Rainer; Nieuwenhuizen, Robert P J; Lidke, Keith A; Rieger, Bernd

    2016-01-01

    Most image capturing devices do not directly report the number of detected photons, but a value proportional to the photoelectron charge produced in a photomultiplier tube or collected in a camera pixel. In order to establish the photon count, the gain of the device must be measured, typically by recording tens of calibration images and exploiting the linear relationship between mean intensity and its variance [vanVliet1998]. Here we propose and evaluate a method that obtains the gain from a single acquired image by quantifying out-of-band information. As noise is not limited to the cut-off frequency of the optical transfer function (OTF), estimation of the out-of-band energy relative to the total energy enables computation of the gain. We show on simulation and experimental data that this much simpler procedure, which can be retroactively applied to any image, is comparable in precision to traditional gain calibration procedures.

  18. Using single photons to improve fiber optic communication systems

    Science.gov (United States)

    Pinto, Armando N.; Silva, Nuno A.; Almeida, Álvaro J.; Muga, Nelson J.

    2014-08-01

    We show how to generate, encode, transmit and detect single photons. By using single photons we can address two of the more challenging problems that communication engineers face nowadays: capacity and security. Indeed, by decreasing the number of photons used to encode each bit, we can efficiently explore the full capacity to carry information of optical fibers, and we can guarantee privacy at the physical layer. We present results for single and entangled photon generation. We encode information in the photons polarization and after transmission we retrieve that information. We discuss the impact of fiber birefringence on the photons polarization.

  19. Quantum Overloading Cryptography Using Single-Photon Nonlocality

    Institute of Scientific and Technical Information of China (English)

    TAN Yong-Gang; CAI Qing-Yu; SHI Ting-Yun

    2007-01-01

    @@ Using the single-photon nonlocality, we propose a quantum novel overloading cryptography scheme, in which a single photon carries two bits information in one-way quantum channel. Two commutative modes of the single photon, the polarization mode and the spatial mode, are used to encode secret information. Strict time windows are set to detect the impersonation attack. The spatial mode which denotes the existence of photons is noncommutative with the phase of the photon, so that our scheme is secure against photon-number-splitting attack. Our protocol may be secure against individual attack.

  20. Extraction of a single photon from an optical pulse

    Science.gov (United States)

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

    2016-01-01

    Removing a single photon from a pulse is one of the most elementary operations that can be performed on light, having both fundamental significance and practical applications in quantum communication and computation. So far, photon subtraction, in which the removed photon is detected and therefore irreversibly lost, has been implemented in a probabilistic manner with inherently low success rates using low-reflectivity beam splitters. Here we demonstrate a scheme for the deterministic extraction of a single photon from an incoming pulse. The removed photon is diverted to a different mode, enabling its use for other purposes, such as a photon number-splitting attack on quantum key distribution protocols. Our implementation makes use of single-photon Raman interaction (SPRINT) with a single atom near a nanofibre-coupled microresonator. The single-photon extraction probability in our current realization is limited mostly by linear loss, yet probabilities close to unity should be attainable with realistic experimental parameters.

  1. Single-photon absorber based on strongly interacting Rydberg atoms

    CERN Document Server

    Tresp, Christoph; Mirgorodskiy, Ivan; Gorniaczyk, Hannes; Paris-Mandoki, Asaf; Hofferberth, Sebastian

    2016-01-01

    Removing exactly one photon from an arbitrary input pulse is an elementary operation in quantum optics and enables applications in quantum information processing and quantum simulation. Here we demonstrate a deterministic single-photon absorber based on the saturation of an optically thick free-space medium by a single photon due to Rydberg blockade. Single-photon subtraction adds a new component to the Rydberg quantum optics toolbox, which already contains photonic logic building-blocks such as single-photon sources, switches, transistors, and conditional $\\pi$-phase shifts. Our approach is scalable to multiple cascaded absorbers, essential for preparation of non-classical light states for quantum information and metrology applications, and, in combination with the single-photon transistor, high-fidelity number-resolved photon detection.

  2. Single-photon imaging in complementary metal oxide semiconductor processes

    NARCIS (Netherlands)

    Charbon, E.

    2014-01-01

    This paper describes the basics of single-photon counting in complementary metal oxide semiconductors, through single-photon avalanche diodes (SPADs), and the making of miniaturized pixels with photon-counting capability based on SPADs. Some applications, which may take advantage of SPAD image senso

  3. Integrated spatial multiplexing of heralded single photon sources

    CERN Document Server

    Collins, Matthew J; Rey, Isabella H; Vo, Trung D; He, Jiakun; Shahnia, Shayan; Reardon, Christopher; Steel, M J; Krauss, Thomas F; Clark, Alex S; Eggleton, Benjamin J

    2013-01-01

    The non-deterministic nature of photon sources is a key limitation for single photon quantum processors. Spatial multiplexing overcomes this by enhancing the heralded single photon yield without enhancing the output noise. Here the intrinsic statistical limit of an individual source is surpassed by spatially multiplexing two monolithic silicon correlated photon pair sources, demonstrating a 62.4% increase in the heralded single photon output without an increase in unwanted multi-pair generation. We further demonstrate the scalability of this scheme by multiplexing photons generated in two waveguides pumped via an integrated coupler with a 63.1% increase in the heralded photon rate. This demonstration paves the way for a scalable architecture for multiplexing many photon sources in a compact integrated platform and achieving efficient two photon interference, required at the core of optical quantum computing and quantum communication protocols.

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

    Science.gov (United States)

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

    2017-01-01

    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. PMID:28240245

  5. Quantum Logic with Cavity Photons From Single Atoms

    Science.gov (United States)

    Holleczek, Annemarie; Barter, Oliver; Rubenok, Allison; Dilley, Jerome; Nisbet-Jones, Peter B. R.; Langfahl-Klabes, Gunnar; Marshall, Graham D.; Sparrow, Chris; O'Brien, Jeremy L.; Poulios, Konstantinos; Kuhn, Axel; Matthews, Jonathan C. F.

    2016-07-01

    We demonstrate quantum logic using narrow linewidth photons that are produced with an a priori nonprobabilistic scheme from a single 87Rb atom strongly coupled to a high-finesse cavity. We use a controlled-not gate integrated into a photonic chip to entangle these photons, and we observe nonclassical correlations between photon detection events separated by periods exceeding the travel time across the chip by 3 orders of magnitude. This enables quantum technology that will use the properties of both narrow-band single photon sources and integrated quantum photonics.

  6. Single-photon transistor in circuit quantum electrodynamics.

    Science.gov (United States)

    Neumeier, Lukas; Leib, Martin; Hartmann, Michael J

    2013-08-01

    We introduce a circuit quantum electrodynamical setup for a "single-photon" transistor. In our approach photons propagate in two open transmission lines that are coupled via two interacting transmon qubits. The interaction is such that no photons are exchanged between the two transmission lines but a single photon in one line can completely block or enable the propagation of photons in the other line. High on-off ratios can be achieved for feasible experimental parameters. Our approach is inherently scalable as all photon pulses can have the same pulse shape and carrier frequency such that output signals of one transistor can be input signals for a consecutive transistor.

  7. A solid-state single-photon filter

    Science.gov (United States)

    de Santis, Lorenzo; Antón, Carlos; Reznychenko, Bogdan; Somaschi, Niccolo; Coppola, Guillaume; Senellart, Jean; Gómez, Carmen; Lemaître, Aristide; Sagnes, Isabelle; White, Andrew G.; Lanco, Loïc; Auffèves, Alexia; Senellart, Pascale

    2017-07-01

    A strong limitation of linear optical quantum computing is the probabilistic operation of two-quantum-bit gates based on the coalescence of indistinguishable photons. A route to deterministic operation is to exploit the single-photon nonlinearity of an atomic transition. Through engineering of the atom-photon interaction, phase shifters, photon filters and photon-photon gates have been demonstrated with natural atoms. Proofs of concept have been reported with semiconductor quantum dots, yet limited by inefficient atom-photon interfaces and dephasing. Here, we report a highly efficient single-photon filter based on a large optical nonlinearity at the single-photon level, in a near-optimal quantum-dot cavity interface. When probed with coherent light wavepackets, the device shows a record nonlinearity threshold around 0.3 ± 0.1 incident photons. We demonstrate that 80% of the directly reflected light intensity consists of a single-photon Fock state and that the two- and three-photon components are strongly suppressed compared with the single-photon one.

  8. Generation and Detection of Infrared Single Photons and their Applications

    Institute of Scientific and Technical Information of China (English)

    ZENG He-ping; WU Guang; WU E; PAN Hai-feng; ZHOU Chun-yuan; WU E.,F.Treussart; J.-F.Roch

    2006-01-01

    Unbreakable secret communication has been a dream from ancient time.It is quantum physics that gives us hope to turn this wizardly dream into reality.The rapid development of quantum cryptography may put an end to the history of eavesdropping.This will be largely due to the advanced techniques related to single quanta,especially infrared single photons.In this paper,we report on our research works on single-photon control for quantum cryptography,ranging from single-photon generation to single-photon detection and their applications.

  9. 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

    We review the recent development of high efficiency single photon sources based on a single quantum dot in a photonic wire. Unlike cavity-based devices, very pure single photon emission and efficiencies exceeding 0.7 photon per pulse are jointly demonstrated under non-resonant pumping conditions....... 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...

  10. Controllable single photon stimulation of retinal rod cells

    CERN Document Server

    Phan, Nam Mai; Bessarab, Dmitri A; Krivitsky, Leonid A

    2013-01-01

    Retinal rod cells are commonly assumed to be sensitive to single photons [1, 2, 3]. Light sources used in prior experiments exhibit unavoidable fluctuations in the number of emitted photons [4]. This leaves doubt about the exact number of photons used to stimulate the rod cell. In this letter, we interface rod cells of Xenopus laevis with a light source based on Spontaneous Parametric Down Conversion (SPDC) [5], which provides one photon at a time. Precise control of generation of single photons and directional delivery enables us to provide unambiguous proof of single photon sensitivity of rod cells without relying on the statistical assumptions. Quantum correlations between single photons in the SPDC enable us to determine quantum efficiency of the rod cell without pre-calibrated reference detectors [6, 7, 8]. These results provide the path for exploiting resources offered by quantum optics in generation and manipulation of light in visual studies. From a more general perspective, this method offers the ult...

  11. Characterization of APDs for single photon counting

    Energy Technology Data Exchange (ETDEWEB)

    Buglak, Wladimir; Hannen, Volker; Joehren, Raphael; Surholt, Martin; Vollbrecht, Jonas; Weinheimer, Christian [Muenster Univ. (Germany). Inst. fuer Kernphysik; Noertershaeuser, Wilfried [Mainz Univ. (Germany). Inst. fuer Kernchemie; GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Sanchez, Rodolfo [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany)

    2013-07-01

    For the SPECTRAP experiment at GSI, Germany, a detector system with single-photon counting capability operating in the wavelength region from 300 nm up to 1100 nm has been developed at the University of Muenster. The detector system utilises a silicon avalanche photo diode (APD) cooled to liquid nitrogen temperatures and operated near the breakdown voltage to obtain high gain values. While the current setup uses a 2 x 2 mm{sup 2} APD (type RMD S0223), it would be advantageous to have a larger active area for easier adjustment of the experiment optics. On the other hand a larger active area is accompanied by increased thermal noise which might harm the photon counting performance of the device. The characterization of a 8 x 8 mm{sup 2} APD (RMD S0814) is the subject of this poster. Furthermore a signal analysis software was developed to supress noise signals, e.g. caused by microphonic effects. The software processes signal waveforms recorded by a Flash ADC and should allow for a lower trigger threshold and thus higher detection efficiency.

  12. Circuit electromechanics with single photon strong coupling

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Zheng-Yuan, E-mail: zyxue@scnu.edu.cn; Yang, Li-Na [Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, and School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China); Zhou, Jian, E-mail: jianzhou8627@163.com [Department of Electronic Communication Engineering, Anhui Xinhua University, Hefei 230088 (China); Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, and School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China)

    2015-07-13

    In circuit electromechanics, the coupling strength is usually very small. Here, replacing the capacitor in circuit electromechanics by a superconducting flux qubit, we show that the coupling among the qubit and the two resonators can induce effective electromechanical coupling which can attain the strong coupling regime at the single photon level with feasible experimental parameters. We use dispersive couplings among two resonators and the qubit while the qubit is also driven by an external classical field. These couplings form a three-wave mixing configuration among the three elements where the qubit degree of freedom can be adiabatically eliminated, and thus results in the enhanced coupling between the two resonators. Therefore, our work constitutes the first step towards studying quantum nonlinear effect in circuit electromechanics.

  13. 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.

  14. 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....

  15. High performance guided-wave asynchronous heralded single photon source

    OpenAIRE

    Alibart, Olivier; Ostrowsky, Daniel Barry; Baldi, Pascal; Tanzilli, Sébastien

    2005-01-01

    International audience; We report on a guided wave heralded photon source based on the creation of non-degenerate photon pairs by spontaneous parametric down conversion in a Periodically Poled Lithium Niobate waveguide. Using the signal photon at 1310 nm as a trigger, a gated detection process permits announcing the arrival of single photons at 1550 nm at the output of a single mode optical fiber with a high probability of 0.38. At the same time the multi-photon emission probability is reduce...

  16. Electromagnetic fields, size, and copy of a single photon

    CERN Document Server

    Liu, Shan-Liang

    2016-01-01

    We propose the expressions of electromagnetic fields of a single photon which properly describe the known characteristics of a photon, derive the relations between the photon size and wavelength on basis of the expressions, reveal the differences between a photon and its copy, and give the specific expressions of annihilation and creation operators of a photon. The results show that a photon has length of half the wavelength, and its radius is proportional to square root of the wavelength; a photon and its copy have the phase difference of {\\pi} and constitute a phase-entangled state; the N-photon phase-entangled state, which is formed by the sequential stimulated emission and corresponds to the wave train in optics, is not a coherent state, but it is the eigenstate of the number operator of photons.

  17. Broadband Purcell enhancement in highly efficient photonic nanowire-based single-photon sources

    DEFF Research Database (Denmark)

    Gregersen, Niels; McCutcheon, Dara; Mørk, Jesper;

    2016-01-01

    The photonic nanowire single-photon source design approach allows for efficient broadband coupling between a quantum dot and a 1D photonic environment. In this work, we introduce weak cavity effects to the design by implementing a distributed Bragg reflector in the inverted taper. This leads to b...

  18. 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...

  19. Two-order Interference of Single Photon

    Institute of Scientific and Technical Information of China (English)

    JIANG Yunkun; LI Jian; SHI Baosen; FAN Xiaofeng; GUO Guangcan

    2000-01-01

    A pair of photons called signal and idler photons, respectively, are produced through the nonlinear process of type-I spontaneous parametric downconversion in BBO crystal pumped by the second-harmonic wave of a Ti:sapphire femtosecond laser pulse. The two-order interference phenomenon of the signal photon in Michelson interferometer is observed and give an analysis in detail.

  20. 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.

  1. Analysis of Photonic Quantum Nodes Based on Deterministic Single-Photon Raman Passage

    CERN Document Server

    Rosenblum, Serge

    2014-01-01

    The long-standing goal of deterministically controlling a single photon using another was recently realized in various experimental settings. Among these, a particularly attractive demonstration relied on deterministic single-photon Raman passage in a three-level Lambda system coupled to a single-mode waveguide. Beyond the ability to control the direction of propagation of one photon by the direction of another photon, this scheme can also perform as a passive quantum memory and a universal quantum gate. Relying on interference, this all-optical, coherent scheme requires no additional control fields, and can therefore form the basis for scalable quantum networks composed of passive quantum nodes that interact with each other only with single photon pulses. Here we present an analytical and numerical study of deterministic single-photon Raman passage, and characterise its limitations and the parameters for optimal operation. Specifically, we study the effect of losses and the presence of multiple excited state...

  2. Single and few photon avalanche photodiode detection process study

    Science.gov (United States)

    Blazej, Josef; Prochazka, Ivan

    2009-07-01

    We are presenting the results of the study of the Single Photon Avalanche Diode (SPAD) pulse response risetime and its dependence on several key parameters. We were investigating the unique properties of K14 type SPAD with its high delay uniformity of 200 μm active area and the correlation between the avalanche buildup time and the photon number involved in the avalanche trigger. The detection chip was operated in a passive quenching circuit with active gating. This setup enabled us to monitor the diode reverse current using an electrometer, a fast digitizing oscilloscope, and using a custom design comparator circuit. The electrometer reading enabled to estimate the photon number per detection event, independently on avalanche process. The avalanche build up was recorded on the oscilloscope and processed by custom designed waveform analysis package. The correlation of avalanche build up to the photon number, bias above break, photon absorption location, optical pulse length and photon energy was investigated in detail. The experimental results are presented. The existing solid state photon counting detectors have been dedicated for picosecond resolution and timing stability of single photon events. However, the high timing stability is maintained for individual single photons detection, only. If more than one photon is absorbed within the detector time resolution, the detection delay will be significantly affected. This fact is restricting the application of the solid state photon counters to cases where single photons may be guaranteed, only. For laser ranging purposes it is highly desirable to have a detector, which detects both single photon and multi photon signals with picoseconds stability. The SPAD based photon counter works in a purely digital mode: a uniform output signal is generated once the photon is detected. If the input signal consists of several photons, the first absorbed one triggers the avalanche. Obviously, for multiple photon signals, the

  3. Heralded single-photon source in a III-V photonic crystal.

    Science.gov (United States)

    Clark, Alex S; Husko, Chad; Collins, Matthew J; Lehoucq, Gaelle; Xavier, Stéphane; De Rossi, Alfredo; Combrié, Sylvain; Xiong, Chunle; Eggleton, Benjamin J

    2013-03-01

    In this Letter we demonstrate heralded single-photon generation in a III-V semiconductor photonic crystal platform through spontaneous four-wave mixing. We achieve a high brightness of 3.4×10(7) pairs·s(-1) nm(-1) W(-1) facilitated through dispersion engineering and the suppression of two-photon absorption in the gallium indium phosphide material. Photon pairs are generated with a coincidence-to-accidental ratio over 60 and a low g(2) (0) of 0.06 proving nonclassical operation in the single photon regime.

  4. Nondestructive photon detection using a single rare-earth ion coupled to a photonic cavity

    Science.gov (United States)

    O'Brien, Chris; Zhong, Tian; Faraon, Andrei; Simon, Christoph

    2016-10-01

    We study the possibility of using single rare-earth ions coupled to a photonic cavity with high cooperativity for performing nondestructive measurements of photons, which would be useful for global quantum networks and photonic quantum computing. We calculate the achievable fidelity as a function of the parameters of the rare-earth ion and photonic cavity, which include the ion's optical and spin dephasing rates, the cavity linewidth, the single-photon coupling to the cavity, and the detection efficiency. We suggest a promising experimental realization using current state-of-the-art technology in Nd:YVO4.

  5. 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...

  6. Secure quantum dialogue based on single-photon

    Institute of Scientific and Technical Information of China (English)

    Ji Xin; Zhang Shou

    2006-01-01

    In this paper a quantum dialogue scheme is proposed by using N batches of single photons. The same secret message is encoded on each batch of single photons by the sender with two different unitary operations, and then the N batches of single photons are sent to the receiver. After eavesdropping check, the message is encoded on the one remaining batch by the receiver. It is shown that the intercept-and-resend attack and coupling auxiliary modes attack can be resisted more efficiently, because the photons are sent only once in our quantum dialogue scheme.

  7. Polarization-correlated photon pairs from a single ion

    CERN Document Server

    Rohde, F; Piro, N; Almendros, M; Schuck, C; Dubin, F; Eschner, J

    2009-01-01

    In the fluorescence light of a single atom, the probability for emission of a photon with certain polarization depends on the polarization of the photon emitted immediately before it. Here correlations of such kind are investigated with a single trapped calcium ion by means of second order correlation functions. A theoretical model is developed and fitted to the experimental data, which show 91% probability for the emission of polarization-correlated photon pairs within 24 ns.

  8. HAPD time-resolution study under single-photon irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Matsui, S.; Akatsu, M.; Enari, Y.; Fujimoto, K.; Higashino, Y.; Hirose, M.; Hokuue, T.; Inami, K.; Ishikawa, A.; Matsumoto, T.; Misono, K.; Ohshima, T. E-mail: ohshima@hepl.phys.nagoya-u.ac.jp; Sugi, A.; Sugiyama, A.; Suzuki, S.; Tomoto, M

    2001-05-01

    We have studied the timing property of a Hybrid Avalanche PhotoDiode, Hamamatsu R7110U-07, and attained a time resolution of {sigma}{sub t}{approx}150 ps for single photons and {<=}100 ps for a few photons under certain conditions of photocathode voltage and diode reverse bias voltage. Relation between the achievable timing resolution and a multiplication gain is discussed, especially in realizing {sigma}{sub t}{<=}100 ps for single photons.

  9. Quasi-secure quantum dialogue using single photons

    Institute of Scientific and Technical Information of China (English)

    YANG; YuGuang; WEN; QiaoYan

    2007-01-01

    A quasi-secure quantum dialogue protocol using single photons was proposed. Different from the previous entanglement-based protocols, the present protocol uses batches of single photons which run back and forth between the two parties. A round run for each photon makes the two parties each obtain a classical bit of information. So the efficiency of information transmission can be increased. The present scheme is practical and well within the present-day technology.

  10. Tunable single-photon frequency conversion in a Sagnac interferometer

    Science.gov (United States)

    Yan, Wei-Bin; Huang, Jin-Feng; Fan, Heng

    2013-12-01

    Quantum information carriers like photons might be manipulated, stored and transmitted in different quantum systems. It is important to integrate those systems efficiently. The capability of converting photons from one wavelength to another wavelength is a key requirement for combining the photons in telecommunications band for quantum transmission and the photons in near-visible band for quantum storage. Here, we investigate the tunable single-photon frequency conversion in the five-level emitter-Sagnac interferometer system. We show that the efficient single-photon conversion can be achieved in this scheme, at the same time, the frequencies of the input and output photons can be tuned in a large scale by controlling the frequencies and Rabi frequencies of the external driving fields. The realization of this scheme may lead to the efficient combination of quantum storage system with the quantum communication system.

  11. 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 number of detected photons by the collection optics per trigger, is desired, and to obtain this high efficiency the photonic environment must be engineered [1] such that all the emitted light couples to the collection optics. A recent design approach is based on a quantum dot placed inside a photonic...... nanowire (Fig. 1). This structure does not feature a cavity but instead relies on a geometrical screening effect to efficiently couple photons to the fundamental waveguide mode. Furthermore, the photonic nanowire SPS implements a bottom metal mirror and exploits tapering strategies based on conical tapers...

  12. Room-temperature single-photon sources based on nanocrystal fluorescence in photonic/plasmonic nanostructures

    Science.gov (United States)

    Lukishova, S. G.; Winkler, J. M.; Bissell, L. J.; Mihaylova, D.; Liapis, Andreas C.; Shi, Z.; Goldberg, D.; Menon, V. M.; Boyd, R. W.; Chen, G.; Prasad, P.

    2014-10-01

    Results are presented here towards robust room-temperature SPSs based on fluorescence in nanocrystals: colloidal quantum dots, color-center diamonds and doped with trivalent rare-earth ions (TR3+). We used cholesteric chiral photonic bandgap and Bragg-reflector microcavities for single emitter fluorescence enhancement. We also developed plasmonic bowtie nanoantennas and 2D-Si-photonic bandgap microcavities. The paper also provides short outlines of other technologies for room-temperature single-photon sources.

  13. 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.

  14. Video recording true single-photon double-slit interference

    Science.gov (United States)

    Aspden, Reuben S.; Padgett, Miles J.; Spalding, Gabriel C.

    2016-09-01

    Commercially available cameras do not have a low-enough dark noise to directly capture double-slit interference at the single photon level. In this work, camera noise levels are significantly reduced by activating the camera only when the presence of a photon has been detected by the independent detection of a time-correlated photon produced via parametric down-conversion. This triggering scheme provides the improvement required for direct video imaging of Young's double-slit experiment with single photons, allowing clarified versions of this foundational demonstration. We present video data of the evolving interference patterns. Also, we introduce variations on this experiment aimed at promoting discussion of the role spatial coherence plays in such a measurement, emphasizing complementary aspects of single-photon measurement and highlighting the roles of transverse position and momentum correlations between down-converted photons, including examples of "ghost" imaging and diffraction.

  15. A Bright Single Photon Source Based on a Diamond Nanowire

    CERN Document Server

    Babinec, T; Khan, M; Zhang, Y; Maze, J; Hemmer, P R; Loncar, M

    2009-01-01

    The development of a robust light source that emits one photon at a time is an outstanding challenge in quantum science and technology. Here, at the transition from many to single photon optical communication systems, fully quantum mechanical effects may be utilized to achieve new capabilities, most notably perfectly secure communication via quantum cryptography. Practical implementations place stringent requirements on the device properties, including fast and stable photon generation, efficient collection of photons, and room temperature operation. Single photon light emitting devices based on fluorescent dye molecules, quantum dots, nanowires, and carbon nanotube material systems have all been explored, but none have simultaneously demonstrated all criteria. Here, we describe the design, fabrication, and characterization of a bright source of single photons consisting of an individual Nitrogen-vacancy color center (NV center) in a diamond nanowire operating in ambient conditions. The nanowire plays a posit...

  16. Indistinguishable photon generation from a single quantum dot in a photonic crystal nanocavity

    DEFF Research Database (Denmark)

    Ates, Serkan; Stobbe, Søren; Lodahl, Peter

    Detailed experimental investigations of the indistinguishability of the single photons generated from a single QD in photonic crystal nanocavities will be presented. The influence of the higher order cavity mode excitation in comparison to the aboveband excitation on the indistinguishability of t...

  17. Single photon laser altimeter data processing, analysis and experimental validation

    Science.gov (United States)

    Vacek, Michael; Peca, Marek; Michalek, Vojtech; Prochazka, Ivan

    2015-10-01

    Spaceborne laser altimeters are common instruments on-board the rendezvous spacecraft. This manuscript deals with the altimeters using a single photon approach, which belongs to the family of time-of-flight range measurements. Moreover, the single photon receiver part of the altimeter may be utilized as an Earth-to-spacecraft link enabling one-way ranging, time transfer and data transfer. The single photon altimeters evaluate actual altitude through the repetitive detections of single photons of the reflected laser pulses. We propose the single photon altimeter signal processing and data mining algorithm based on the Poisson statistic filter (histogram method) and the modified Kalman filter, providing all common altimetry products (altitude, slope, background photon flux and albedo). The Kalman filter is extended for the background noise filtering, the varying slope adaptation and the non-causal extension for an abrupt slope change. Moreover, the algorithm partially removes the major drawback of a single photon altitude reading, namely that the photon detection measurement statistics must be gathered. The developed algorithm deduces the actual altitude on the basis of a single photon detection; thus, being optimal in the sense that each detected signal photon carrying altitude information is tracked and no altitude information is lost. The algorithm was tested on the simulated datasets and partially cross-probed with the experimental data collected using the developed single photon altimeter breadboard based on the microchip laser with the pulse energy on the order of microjoule and the repetition rate of several kilohertz. We demonstrated that such an altimeter configuration may be utilized for landing or hovering a small body (asteroid, comet).

  18. Trapping of Single Atoms with Single Photons in Cavity QED

    CERN Document Server

    Doherty, A C; Hood, C J; Kimble, H J

    2000-01-01

    Two recent experiments have reported the trapping of individual atoms inside optical resonators by the mechanical forces associated with single photons [Hood et al., Science 287, 1447 (2000) and Pinkse et al., Nature 404, 365 (2000)]. Here we analyze the trapping dynamics in these settings, focusing on two points of interest. Firstly, we investigate the extent to which light-induced forces in these experiments are distinct from their free-space counterparts. Secondly, we explore the quantitative features of the resulting atomic motion and how these dynamics are mapped onto variations of the intracavity field. Not surprisingly, qualitatively distinct atomic dynamics arise as the coupling and dissipative rates are varied. For the experiment of Hood et al., we show that atomic motion is largely conservative and is predominantly in radial orbits transverse to the cavity axis. A comparison with the free-space theory demonstrates that the fluctuations of the dipole force are suppressed by an order of magnitude. Thi...

  19. Coherence length of photons from a single quantum system

    Science.gov (United States)

    Jelezko, F.; Volkmer, A.; Popa, I.; Rebane, K. K.; Wrachtrup, J.

    2003-04-01

    We present a methodology that allows recording the coherence length of photons emitted by a single quantum system in a solid. The feasibility of this approach is experimentally demonstrated by measuring the self-interference of photons from the zero-phonon line emission of a single nitrogen-vacancy defect in diamond at 1.6 K. The first-order correlation function has been recorded and analyzed in terms of a single exponential decay time. A coherence time of ˜5 ps has been obtained, which is in good agreement with the corresponding spectral line width and demonstrates the feasibility of the Fourier-transform spectroscopy with single photons.

  20. A photon-photon quantum gate based on a single atom in an optical resonator.

    Science.gov (United States)

    Hacker, Bastian; Welte, Stephan; Rempe, Gerhard; Ritter, Stephan

    2016-08-11

    That two photons pass each other undisturbed in free space is ideal for the faithful transmission of information, but prohibits an interaction between the photons. Such an interaction is, however, required for a plethora of applications in optical quantum information processing. The long-standing challenge here is to realize a deterministic photon-photon gate, that is, a mutually controlled logic operation on the quantum states of the photons. This requires an interaction so strong that each of the two photons can shift the other's phase by π radians. For polarization qubits, this amounts to the conditional flipping of one photon's polarization to an orthogonal state. So far, only probabilistic gates based on linear optics and photon detectors have been realized, because "no known or foreseen material has an optical nonlinearity strong enough to implement this conditional phase shift''. Meanwhile, tremendous progress in the development of quantum-nonlinear systems has opened up new possibilities for single-photon experiments. Platforms range from Rydberg blockade in atomic ensembles to single-atom cavity quantum electrodynamics. Applications such as single-photon switches and transistors, two-photon gateways, nondestructive photon detectors, photon routers and nonlinear phase shifters have been demonstrated, but none of them with the ideal information carriers: optical qubits in discriminable modes. Here we use the strong light-matter coupling provided by a single atom in a high-finesse optical resonator to realize the Duan-Kimble protocol of a universal controlled phase flip (π phase shift) photon-photon quantum gate. We achieve an average gate fidelity of (76.2 ± 3.6) per cent and specifically demonstrate the capability of conditional polarization flipping as well as entanglement generation between independent input photons. This photon-photon quantum gate is a universal quantum logic element, and therefore could perform most existing two-photon operations

  1. 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....

  2. III-Nitride high temperature single-photon sources

    Science.gov (United States)

    Bhattacharya, Pallab; Deshpande, Saniya; Frost, Thomas; Hazari, Arnab

    2015-03-01

    Nitride based GaN and InGaN quantum dots are excellent single-photon emitters at high temperature owing to their wide bandgap and large exciton binding energy [1-5]. In this work, two different molecular beam epitaxy (MBE) grown nanostructures have been investigated for single-photon emission: InGaN/GaN disk-in-nanowire and InGaN/GaN self-organized quantum dot. Single-photon emission under both optical and electrical excitation has been observed from a single InGaN quantum contained in a GaN nanowire p-n junction. We demonstrate electrically driven single-photon emission, with a g (2)(0) = 0.35, from a single InGaN quantum dot emitting in the green spectral range (λ=520 nm) up to 125 K. Additionally, a self-organized InGaN/GaN single quantum dot diode was grown and fabricated. Emission from a single quantum dot (λ=620 nm) shows single-photon emission with g(2)(0) = 0.29 at room temperature. On-demand single-photon emission by electrical pumping of the quantum dot at an excitation repetition rate of 200 MHz was demonstrated.

  3. 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

    The development of efficient solid-state sources of single photons is a major challenge in the context of quantum communication,optical quantum information processing and metrology1. Such a source must enable the implementation of a stable, single-photon emitter, like a colour centre in diamond2...... with carefully tailored ends13. Under optical pumping, we demonstrate a record source efficiency of 0.72, combined with pure single-photon emission. This non-resonant approach also provides broadband spontaneous emission control, thus offering appealing novel opportunities for the development of single...

  4. Achieving nonreciprocal unidirectional single-photon quantum transport using the photonic Aharonov-Bohm effect.

    Science.gov (United States)

    Yuan, Luqi; Xu, Shanshan; Fan, Shanhui

    2015-11-15

    We show that nonreciprocal unidirectional single-photon quantum transport can be achieved with the photonic Aharonov-Bohm effect. The system consists of a 1D waveguide coupling to two three-level atoms of the V-type. The two atoms, in addition, are each driven by an external coherent field. We show that the phase of the external coherent field provides a gauge potential for the photon states. With a proper choice of the phase difference between the two coherent fields, the transport of a single photon can exhibit unity contrast in its transmissions for the two propagation directions.

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

    DEFF Research Database (Denmark)

    Gregersen, Niels; Chen, Yuntian; Mørk, Jesper

    2012-01-01

    The photonic nanowire has recently emerged as an promising alternative to microcavity-based single-photon source designs. In this simple structure, a geometrical effect ensures a strong coupling between an embedded emitter and the optical mode of interest and a combination of tapers and mirrors...... 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...

  6. High-yield entangled single photon source

    Science.gov (United States)

    Soh, Daniel B. S.; Bisson, Scott E.

    2016-10-11

    The various technologies presented herein relate to utilizing photons at respective idler and signal frequencies to facilitate generation of photons at a pump frequency. A strong pump field can be applied at the .omega..sub.i and the .omega..sub.s frequencies, with the generated idler and signal pulses being utilized to generate a photon pair at the .omega..sub.p frequency. Further, the idler pump power can be increased relative to the signal pump power such that the pump power P.sub.i>pump power P.sub.s. Such reversed operation (e.g., .omega..sub.i+.omega..sub.s.fwdarw..omega..sub.p1+.omega..sub.p2) can minimize and/or negate Raman scattering effects. By complying with an energy conservation requirement, the .omega..sub.i and .omega..sub.s photons interacting with the material through the four-wave mixing process facilitates the entanglement of the .omega..sub.p1 and .omega..sub.p2 photons. The .omega..sub.i and .omega..sub.s photons can be respectively formed in different length waveguides with a delay utilized to facilitate common timing between the .omega..sub.i and .omega..sub.s photons.

  7. A photon-photon quantum gate based on a single atom in an optical resonator

    Science.gov (United States)

    Hacker, Bastian; Welte, Stephan; Rempe, Gerhard; Ritter, Stephan

    2016-08-01

    That two photons pass each other undisturbed in free space is ideal for the faithful transmission of information, but prohibits an interaction between the photons. Such an interaction is, however, required for a plethora of applications in optical quantum information processing. The long-standing challenge here is to realize a deterministic photon-photon gate, that is, a mutually controlled logic operation on the quantum states of the photons. This requires an interaction so strong that each of the two photons can shift the other’s phase by π radians. For polarization qubits, this amounts to the conditional flipping of one photon’s polarization to an orthogonal state. So far, only probabilistic gates based on linear optics and photon detectors have been realized, because “no known or foreseen material has an optical nonlinearity strong enough to implement this conditional phase shift”. Meanwhile, tremendous progress in the development of quantum-nonlinear systems has opened up new possibilities for single-photon experiments. Platforms range from Rydberg blockade in atomic ensembles to single-atom cavity quantum electrodynamics. Applications such as single-photon switches and transistors, two-photon gateways, nondestructive photon detectors, photon routers and nonlinear phase shifters have been demonstrated, but none of them with the ideal information carriers: optical qubits in discriminable modes. Here we use the strong light-matter coupling provided by a single atom in a high-finesse optical resonator to realize the Duan-Kimble protocol of a universal controlled phase flip (π phase shift) photon-photon quantum gate. We achieve an average gate fidelity of (76.2 ± 3.6) per cent and specifically demonstrate the capability of conditional polarization flipping as well as entanglement generation between independent input photons. This photon-photon quantum gate is a universal quantum logic element, and therefore could perform most existing two-photon

  8. Video recording true single-photon double-slit interference

    CERN Document Server

    Aspden, Reuben S; Spalding, Gabriel C

    2016-01-01

    As normally used, no commercially available camera has a low-enough dark noise to directly produce video recordings of double-slit interference at the photon-by-photon level, because readout noise significantly contaminates or overwhelms the signal. In this work, noise levels are significantly reduced by turning on the camera only when the presence of a photon has been heralded by the arrival, at an independent detector, of a time-correlated photon produced via parametric down-conversion. This triggering scheme provides the improvement required for direct video imaging of Young's double-slit experiment with single photons, allowing clarified versions of this foundational demonstration. Further, we introduce variations on this experiment aimed at promoting discussion of the role spatial coherence plays in such a measurement. We also emphasize complementary aspects of single-photon measurement, where imaging yields (transverse) position information, while diffraction yields the transverse momentum, and highligh...

  9. 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

    The development of efficient solid-state sources of single photons is a major challenge in the context of quantum communication,optical quantum information processing and metrology1. Such a source must enable the implementation of a stable, single-photon emitter, like a colour centre in diamond2...... with carefully tailored ends13. Under optical pumping, we demonstrate a record source efficiency of 0.72, combined with pure single-photon emission. This non-resonant approach also provides broadband spontaneous emission control, thus offering appealing novel opportunities for the development of single-photon......–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...

  10. A Single-Photon Subtractor for Multimode Quantum States

    Science.gov (United States)

    Ra, Young-Sik; Jacquard, Clément; Averchenko, Valentin; Roslund, Jonathan; Cai, Yin; Dufour, Adrien; Fabre, Claude; Treps, Nicolas

    2016-05-01

    In the last decade, single-photon subtraction has proved to be key operations in optical quantum information processing and quantum state engineering. Implementation of the photon subtraction has been based on linear optics and single-photon detection on single-mode resources. This technique, however, becomes unsuitable with multimode resources such as spectrally multimode squeezed states or continuous variables cluster states. We implement a single-photon subtractor for such multimode resources based on sum-frequency generation and single-photon detection. An input multimode quantum state interacts with a bright control beam whose spectrum has been engineered through ultrafast pulse-shaping. The multimode quantum state resulting from the single-photon subtractor is analyzed with multimode homodyne detection whose local oscillator spectrum is independently engineered. We characterize the single-photon subtractor via coherent-state quantum process tomography, which provides its mode-selectivity and subtraction modes. The ability to simultaneously control the state engineering and its detection ensures both flexibility and scalability in the production of highly entangled non-Gaussian quantum states.

  11. 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

    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 ...... can be improved by a further 4% by engineering the dispersion. Efficient single-photon absorption by a single emitter has potential applications in quantum communication and quantum computation....

  12. Single-photon heat conduction in electrical circuits

    CERN Document Server

    Jones, P J; Tan, K Y; Möttönen, M

    2011-01-01

    We study photonic heat conduction between two resistors coupled weakly to a single superconducting microwave cavity. At low enough temperature, the dominating part of the heat exchanged between the resistors is transmitted by single-photon excitations of the fundamental mode of the cavity. This manifestation of single-photon heat conduction should be experimentally observable with the current state of the art. Our scheme can possibly be utilized in remote interference-free temperature control of electric components and environment engineering for superconducting qubits coupled to cavities.

  13. 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

    unprecedented potential to be controlled with atomic layer accuracy without random alloying. We show for the first time that crystal phase quantum dots are a source of pure single-photons and cascaded photon-pairs from type II transitions with excellent optical properties in terms of intensity and line width...... quantum optical properties for single photon application and quantum optics.......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 offer...

  14. Superconducting single photon detectors integrated with diamond nanophotonic circuits

    CERN Document Server

    Rath, Patrik; Ferrari, Simone; Sproll, Fabian; Lewes-Malandrakis, Georgia; Brink, Dietmar; Ilin, Konstantin; Siegel, Michael; Nebel, Christoph; Pernice, Wolfram

    2015-01-01

    Photonic quantum technologies promise to repeat the success of integrated nanophotonic circuits in non-classical applications. Using linear optical elements, quantum optical computations can be performed with integrated optical circuits and thus allow for overcoming existing limitations in terms of scalability. Besides passive optical devices for realizing photonic quantum gates, active elements such as single photon sources and single photon detectors are essential ingredients for future optical quantum circuits. Material systems which allow for the monolithic integration of all components are particularly attractive, including III-V semiconductors, silicon and also diamond. Here we demonstrate nanophotonic integrated circuits made from high quality polycrystalline diamond thin films in combination with on-chip single photon detectors. Using superconducting nanowires coupled evanescently to travelling waves we achieve high detection efficiencies up to 66 % combined with low dark count rates and timing resolu...

  15. Economical quantum secure direct communication network with single photons

    Institute of Scientific and Technical Information of China (English)

    Deng Fu-Guo; Li Xi-Han; Li Chun-Yan; Zhou Ping; Zhou Hong-Yu

    2007-01-01

    In this paper a scheme for quantum secure direct communication (QSDC) network is proposed with a sequence of polarized single photons. The single photons are prepared originally in the same state |0> by the servers on the network,which will reduce the difficulty for the legitimate users to check eavesdropping largely. The users code the information on the single photons with two unitary operations which do not change their measuring bases. Some decoy photons,which are produced by operating the sample photons with a Hadamard, are used for preventing a potentially dishonest server from eavesdropping the quantum lines freely. This scheme is an economical one as it is the easiest way for QSDC network communication securely.

  16. Polarization Properties of Quantum-Dot-Based Single Photon Sources

    Institute of Scientific and Technical Information of China (English)

    HAN Shuo; HAO Zhi-Biao; LUO Yi

    2007-01-01

    Polarization properties of single photons emitted by optical pumping from a single quantum dot (QD) are studied by using a four-level system model. The model is capable of explaining the polarization uncertainty observed in single photon emission experiments. It is found that the dependence of photon emission efficiency and polarization visibility on pump power are opposite in general cases. By employing QDs with small size and strong carrier confinement, the photon polarization visibility under high pump power can be improved. In addition, embedding a QD into a well designed microcavity is also found to be favourable, whereas the trade-off between high polarization visibility and multi-photon emission is noted.

  17. 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

    2017-02-24

    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.

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

    DEFF Research Database (Denmark)

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

    . 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...

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

    DEFF Research Database (Denmark)

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

    . 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...

  20. 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.

  1. 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...

  2. Electrically pumped photonic nanowire single-photon source with an efficienty of 89%

    DEFF Research Database (Denmark)

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

    2011-01-01

    We propose a new electrically-pumped single-photon source design based on a quantum dot in a photonic nanowire. For realistic parameters, the design features an efficiency of 89 % predicted by numerical simulations. Unlike cavity-based designs, our approach allows for broadband spontaneous emission...

  3. 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...

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

    Science.gov (United States)

    Privitera, Simona; Tudisco, Salvatore; Lanzanò, Luca; Musumeci, Francesco; Pluchino, Alessandro; Scordino, Agata; Campisi, Angelo; Cosentino, Luigi; Finocchiaro, Paolo; Condorelli, Giovanni; Mazzillo, Massimo; Lombardo, Salvo; Sciacca, Emilio

    2008-01-01

    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. PMID:27873777

  5. 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.

  6. Single-photon quantum router with multiple output ports.

    Science.gov (United States)

    Yan, Wei-Bin; Fan, Heng

    2014-04-28

    The routing capability is a requisite in quantum network. Although the quantum routing of signals has been investigated in various systems both in theory and experiment, the general form of quantum routing with many output terminals still needs to be explored. Here we propose a scheme to achieve the multi-channel quantum routing of the single photons in a waveguide-emitter system. The channels are composed by the waveguides and are connected by intermediate two-level emitters. By adjusting the intermediate emitters, the output channels of the input single photons can be controlled. This is demonstrated in the cases of one output channel, two output channels and the generic N output channels. The results show that the multi-channel quantum routing of single photons can be well achieved in the proposed system. This offers a scheme for the experimental realization of general quantum routing of single photons.

  7. 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...

  8. Continuous variable teleportation of single photon states (Proceedings version)

    OpenAIRE

    Ide, Toshiki; Hofmann, Holger F.; Kobayashi, Takayoshi; Furusawa, Akira

    2001-01-01

    We investigate the changes to a single photon state caused by the non-maximal entanglement in continuous variable quantum teleportation. It is shown that the teleportation measurement introduces field coherence in the output.

  9. The analysis of the integral gated mode single photon detector

    Institute of Scientific and Technical Information of China (English)

    Wei Zheng-Jun; Li Kai-Zhen; Zhou Peng; Wang Jin-Dong; Liao Chang-Jun; Guo Jian-Ping; Liang Rui-Sheng; Liu Song-Hao

    2008-01-01

    This paper critically analyses and simulates the circuit configuration of the integral gated mode single photon detector which is proposed for eliminating the transient spikes problem of conventional gated mode single photon detector.The relationship between the values of the circuit elements and the effect of transient spikes cancellation has been obtained.With particular emphasis,the bias voltage of the avalanche photodiode and the output signal voltage of the integrator have been calculated.The obtained analysis results indicate that the output signal voltage of the integrator only relates to the total quantity of electricity of the avalanche charges by choosing the correct values of the circuit elements and integral time interval.These results can be used to optimize the performance of single photon detectors and provide guides for the design of single photon detectors.

  10. Correction of ultraviolet single photon counting image distortion

    Institute of Scientific and Technical Information of China (English)

    Xinghua Zhang; Baosheng Zhao; Zhenhua Miao; Wei Li; Xiangping Zhu; Yong'an Liu; Wei Zou

    2008-01-01

    Single photon counting imaging technology has been widely used in space environment detection, astronomy observation, nuclear physics, and ultraweak bioluminescence. However, the distortion of the single photon counting image will badly affect the measurement results. Therefore, the correction of distortion for single photon counting image is very significant. Ultraviolet single photon imaging system with wedge and strip anode is introduced and the influence factor leading to image distortion is analyzed. To correct original distorted image, three different image correction methods, namely, the physical correction, the global correction, and the local correction, are applied. In addition, two parameters, i.e, the position index and the linearity index, are defined to evaluate the performance of the three methods. The results suggest that the correction methods can improve the quality of the initial image without losing gray information of each counting light spot. And the local correction can provide the best visual inspections and performance evaluation among the three methods.

  11. Single-Photon Momentum Displacement in Resonator Array with Optomechanics

    Science.gov (United States)

    Tian, T.; Li, Q.; Zhou, Lan; Song, L. J.

    2016-10-01

    We present the single-photon scattering in a resonator array system with optomechanical by solving the Lippmann-Schwinger equation iteratively. Up to the first order of the radiation pressure interaction, the single-photon transport is formulated as a three-channel scattering process. We calculate the scattering currents in different channels and obtain the transmission spectrum which shows a momentum displacement effect.

  12. Optimal storage and retrieval of single-photon waveforms.

    Science.gov (United States)

    Zhou, Shuyu; Zhang, Shanchao; Liu, Chang; Chen, J F; Wen, Jianming; Loy, M M T; Wong, G K L; Du, Shengwang

    2012-10-22

    We report an experimental demonstration of optimal storage and retrieval of heralded single-photon wave packets using electromagnetically induced transparency (EIT) in cold atoms at a high optical depth. We obtain an optimal storage efficiency of (49 ± 3)% for single-photon waveforms with a temporal likeness of 96%. Our result brings the EIT quantum light-matter interface closer to practical quantum information applications.

  13. Potential of semiconductor nanowires for single photon sources

    NARCIS (Netherlands)

    Harmand, J.-C.; Liu, L.; Patriarche, G.; Tchernycheva, M.; Akopian, N.; Perinetti, U.; Zwiller, V.

    2009-01-01

    The catalyst-assisted growth of semiconductor nanowires heterostructures offers a very flexible way to design and fabricate single photon emitters. The nanowires can be positioned by organizing the catalyst prior to growth. Single quantum dots can be formed in the core of single nanowires which can

  14. Efficient room-temperature source of polarized single photons

    Science.gov (United States)

    Lukishova, Svetlana G.; Boyd, Robert W.; Stroud, Carlos R.

    2007-08-07

    An efficient technique for producing deterministically polarized single photons uses liquid-crystal hosts of either monomeric or oligomeric/polymeric form to preferentially align the single emitters for maximum excitation efficiency. Deterministic molecular alignment also provides deterministically polarized output photons; using planar-aligned cholesteric liquid crystal hosts as 1-D photonic-band-gap microcavities tunable to the emitter fluorescence band to increase source efficiency, using liquid crystal technology to prevent emitter bleaching. Emitters comprise soluble dyes, inorganic nanocrystals or trivalent rare-earth chelates.

  15. 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.

  16. 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.

  17. Combustion study with synchrotron radiation single photon ionization technique

    Institute of Scientific and Technical Information of China (English)

    YANG Rui; WANG Jing; HUANG Chaoqun; YANG Bin; WEI Lixia; SHAN Xiaobin; SHENG Liusi; ZHANG Yunwu; QI Fei

    2005-01-01

    Here we report a combustion endstation at National Synchrotron Radiation Laboratory (NSRL) and some primary experimental results. Synchrotron radiation can provide the tunable vacuum ultraviolet (VUV) photon with the high intensity and the good collimation. VUV photoionization is a single-photon ionization process. Combined with molecular-beam mass spectrometry (MBMS), the VUV single-photon ionization can be applied to detect the combustion products, especially the intermediates and free radicals produced from combustion process. This method is proved to be a powerful tool for combustion study, which could be helpful for developing combustion kinetic models and understanding the mechanism of combustion reactions.

  18. Photonic gap vanishing in one-dimensional photonic crystals with single-negative metamaterials

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yihang, E-mail: kallenmail@sina.com [Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong (China); Laboratory of Quantum Information Technology, School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou (China); Wang, Yu; Leung, C.W.; Hu, Mingzhe; Chan, H.L.W. [Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong (China)

    2011-06-13

    The properties of photonic band gap in one-dimensional photonic crystals composed of single-negative metamaterials are studied theoretically. Our study shows that the photonic gap will vanish at a certain incident angle when both the phase-match and impedance-match conditions are satisfied simultaneously, suggesting that the bandwidth and location of the photonic gap are strongly dependent on the incident angle and polarization. However, the photonic gap will not vanish and may become insensitive to the incident angle when the two match conditions cannot be met. Our study also shows that losses in metamaterials have little effect on the properties of the photonic gap. -- Highlights: → Photonic gap of 1D photonic crystal containing metamaterials was investigated. → The gap can be designed to be sensitive or insensitive to the incident angle. → The gap can be designed to be close at a specific incident angle. → Conditions for photonic gap vanishing were proposed. → Losses of metamaterials have little effect on the properties of the photonic gap.

  19. Localized Polymerization Using Single Photon Photoinitiators in Two-photon process for Fabricating Subwavelength Structures

    CERN Document Server

    Ummethala, Govind; Chaudhary, Raghvendra P; Hawal, Suyog; Saxena, Sumit; Shukla, Shobha

    2016-01-01

    Localized polymerization in subwavelength volumes using two photon dyes has now become a well-established method for fabrication of subwavelength structures. Unfortunately, the two photon absorption dyes used in such process are not only expensive but also proprietary. LTPO-L is an inexpensive, easily available single photon photoinitiator and has been used extensively for single photon absorption of UV light for polymerization. These polymerization volumes however are not localized and extend to micron size resolution having limited applications. We have exploited high quantum yield of radicals of LTPO-Lfor absorption of two photons to achieve localized polymerization in subwavelength volumes, much below the diffraction limit. Critical concentration (10wt%) of LTPO-Lin acrylate (Sartomer) was found optimal to achieve subwavelength localized polymerization and has been demonstrated by fabricating 2D/3D complex nanostructures and functional devices such as variable polymeric gratings with nanoscaled subwavelen...

  20. Single-photon detection timing jitter in a visible light photon counter

    CERN Document Server

    Baek, Burm; Stevens, Martin J; Kim, Jungsang; Hogue, Henry H; Nam, Sae Woo

    2009-01-01

    Visible light photon counters (VLPCs) offer many attractive features as photon detectors, such as high quantum efficiency and photon number resolution. We report measurements of the single-photon timing jitter in a VLPC, a critical performance factor in a time-correlated single-photon counting measurement, in a fiber-coupled closed-cycle cryocooler. The measured timing jitter is 240 ps full-width-at-half-maximum at a wavelength of 550 nm, with a dark count rate of 25 000 counts per second. The timing jitter increases modestly at longer wavelengths to 300 ps at 1000 nm, and increases substantially at lower bias voltages as the quantum efficiency is reduced.

  1. Entanglement-preserving absorption of single SPDC photons by a single atom

    CERN Document Server

    Huwer, J; Piro, N; Schug, M; Dubin, F; Eschner, J

    2011-01-01

    We study the controlled interaction between a single trapped Ca40+ ion and single photons belonging to entangled photon pairs. The ion is prepared as a polarization-sensitive single-photon absorber; the absorption of one photon from a pair is marked by a quantum jump of the atomic state and heralded by the coincident detection of the entangled partner photon. For three polarization basis settings of absorption and detection of the herald, we find maximum coincidences always for orthogonal polarizations. Tomographic reconstruction of the biphoton quantum state from the absorption-herald coincidences reveals 93% overlap with the maximally entangled state. This proves that the polarization entanglement shared by the photon pair is preserved in the absorption process and converted to transient photon-atom entanglement.

  2. Quantum teleportation with a quantum dot single photon source.

    Science.gov (United States)

    Fattal, D; Diamanti, E; Inoue, K; Yamamoto, Y

    2004-01-23

    We report the experimental demonstration of a quantum teleportation protocol with a semiconductor single photon source. Two qubits, a target and an ancilla, each defined by a single photon occupying two optical modes (dual-rail qubit), were generated independently by the single photon source. Upon measurement of two modes from different qubits and postselection, the state of the two remaining modes was found to reproduce the state of the target qubit. In particular, the coherence between the target qubit modes was transferred to the output modes to a large extent. The observed fidelity is 80%, in agreement with the residual distinguishability between consecutive photons from the source. An improved version of this teleportation scheme using more ancillas is the building block of the recent Knill, Laflamme, and Milburn proposal for efficient linear optics quantum computation.

  3. Single-photon-level quantum memory at room temperature

    CERN Document Server

    Reim, K F; Lee, K C; Nunn, J; Langford, N K; Walmsley, I A

    2010-01-01

    Quantum memories capable of storing single photons are essential building blocks for quantum information processing, enabling the storage and transfer of quantum information over long distances. Devices operating at room temperature can be deployed on a large scale and integrated into existing photonic networks, but so far warm quantum memories have been susceptible to noise at the single photon level. This problem is circumvented in cold atomic ensembles, but these are bulky and technically complex. Here we demonstrate controllable, broadband and efficient storage and retrieval of weak coherent light pulses at the single-photon level in warm atomic caesium vapour using the far off-resonant Raman memory scheme. The unconditional noise floor is found to be low enough to operate the memory in the quantum regime at room temperature.

  4. 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

  5. Characterizing heralded single-photon sources with imperfect measurement devices

    Energy Technology Data Exchange (ETDEWEB)

    Razavi, M; Soellner, I; Bocquillon, E; Couteau, C; Laflamme, R; Weihs, G [Institute for Quantum Computing, University of Waterloo, 200 University Ave. W, Waterloo, ON N2L 3G1 (Canada)], E-mail: mrazavi@iqc.ca

    2009-06-14

    Any characterization of a single-photon source is not complete without specifying its second-order degree of coherence, i.e., its g{sup (2)} function. An accurate measurement of such coherence functions commonly requires high-precision single-photon detectors, in whose absence only time-averaged measurements are possible. It is not clear, however, how the resulting time-averaged quantities can be used to properly characterize the source. In this paper, we investigate this issue for a heralded source of single photons that relies on continuous-wave parametric down-conversion. By accounting for major shortcomings of the source and the detectors-i.e., the multiple-photon emissions of the source, the time resolution of photodetectors and our chosen width of coincidence window-our theory enables us to infer the true source properties from imperfect measurements. Our theoretical results are corroborated by an experimental demonstration using a PPKTP crystal pumped by a blue laser that results in a single-photon generation rate about 1.2 millions per second per milliwatt of pump power. This work takes an important step towards the standardization of such heralded single-photon sources.

  6. 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.

  7. A silicon carbide room-temperature single-photon source

    Science.gov (United States)

    Castelletto, S.; Johnson, B. C.; Ivády, V.; Stavrias, N.; Umeda, T.; Gali, A.; Ohshima, T.

    2014-02-01

    Over the past few years, single-photon generation has been realized in numerous systems: single molecules, quantum dots, diamond colour centres and others. The generation and detection of single photons play a central role in the experimental foundation of quantum mechanics and measurement theory. An efficient and high-quality single-photon source is needed to implement quantum key distribution, quantum repeaters and photonic quantum information processing. Here we report the identification and formation of ultrabright, room-temperature, photostable single-photon sources in a device-friendly material, silicon carbide (SiC). The source is composed of an intrinsic defect, known as the carbon antisite-vacancy pair, created by carefully optimized electron irradiation and annealing of ultrapure SiC. An extreme brightness (2×106 counts s-1) resulting from polarization rules and a high quantum efficiency is obtained in the bulk without resorting to the use of a cavity or plasmonic structure. This may benefit future integrated quantum photonic devices.

  8. Reading boundless error-free bits using a single photon

    Science.gov (United States)

    Guha, Saikat; Shapiro, Jeffrey H.

    2013-06-01

    We address the problem of how efficiently information can be encoded into and read out reliably from a passive reflective surface that encodes classical data by modulating the amplitude and phase of incident light. We show that nature imposes no fundamental upper limit to the number of bits that can be read per expended probe photon and demonstrate the quantum-information-theoretic trade-offs between the photon efficiency (bits per photon) and the encoding efficiency (bits per pixel) of optical reading. We show that with a coherent-state (ideal laser) source, an on-off (amplitude-modulation) pixel encoding, and shot-noise-limited direct detection (an overly optimistic model for commercial CD and DVD drives), the highest photon efficiency achievable in principle is about 0.5 bits read per transmitted photon. We then show that a coherent-state probe can read unlimited bits per photon when the receiver is allowed to make joint (inseparable) measurements on the reflected light from a large block of phase-modulated memory pixels. Finally, we show an example of a spatially entangled nonclassical light probe and a receiver design—constructible using a single-photon source, beam splitters, and single-photon detectors—that can in principle read any number of error-free bits of information. The probe is a single photon prepared in a uniform coherent superposition of multiple orthogonal spatial modes, i.e., a W state. The code and joint-detection receiver complexity required by a coherent-state transmitter to achieve comparable photon efficiency performance is shown to be much higher in comparison to that required by the W-state transceiver, although this advantage rapidly disappears with increasing loss in the system.

  9. Mode Invisibility and Single Photon Detection

    CERN Document Server

    Onuma-Kalu, Marvellous; Martin-Martinez, Eduardo

    2013-01-01

    We propose a technique to probe the quantum state of light in an optical cavity without significantly altering it. We minimize the interaction of the probe with the field by arranging a setting where the largest contribution to the transition probability is cancelled. We show that we obtain a very good resolution to measure photon population differences between two given Fock states by means of atomic interferometry.

  10. Remote preparation of complex spatial states of single photons and verification by two-photon coincidence experiment.

    Science.gov (United States)

    Kang, Yoonshik; Cho, Kiyoung; Noh, Jaewoo; Vitullo, Dashiell L P; Leary, Cody; Raymer, M G

    2010-01-18

    We propose and provide experimental evidence in support of a theory for the remote preparation of a complex spatial state of a single photon. An entangled two-photon source was obtained by spontaneous parametric down-conversion, and a double slit was placed in the path of the signal photon as a scattering object. The signal photon was detected after proper spatial filtering so that the idler photon was prepared in the corresponding single-photon state. By using a two-photon coincidence measurement, we obtained the Radon transform, at several longitudinal distances, of the single-photon Wigner distribution function modified by the double slit. The experimental results are consistent with the idler photon being in a pure state. An inverse Radon transformation can, in principle, be applied to the measured data to reconstruct the modified single-photon Wigner function, which is a complete representation of the amplitude and phase structure of the scattering object.

  11. 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.

  12. Single-Photon Emission from a Single InAs Quantum Dot

    Institute of Scientific and Technical Information of China (English)

    DOU Xiu-Ming; SUN Bao-Quan; HUANG She-Song; NI Hai-Qiao; NIU Zhi-Chuan

    2008-01-01

    Excitation power-dependent micro-photoluminescence spectra and photon-correlation measurement are used to study the optical properties and photon statistics of single InAs quantum dots.Exciton and biexciton emissions,whose photoluminescence intensities have linear and quadratic excitation power dependences,respectively,are identified.Under pulsed laser excitation,the zero time delay peak of second order correlation function corresponding to exciton emission is well suppressed,which is a clear evidence of single photon emission.

  13. Controlled Single-Photon Emission from a Single Trapped Two-Level Atom

    CERN Document Server

    Darquié, B; Dingjan, J; Beugnon, J; Bergamini, S; Sortais, Y; Messin, G; Browaeys, A; Grangier, P; Darqui\\'{e}, Benoit; Jones, Matthew; Dingjan, Jos; Beugnon, Jerome; Bergamini, Silvia; Sortais, Yvan; Messin, Gaetan; Browaeys, Antoine; Grangier, Philippe

    2005-01-01

    By illuminating an individual rubidium atom stored in a tight optical tweezer with short resonant light pulses, we create an efficient triggered source of single photons with a well-defined polarization. The measured intensity correlation of the emitted light pulses exhibits almost perfect antibunching. Such a source of high rate, fully controlled single photon pulses has many potential applications for quantum information processing.

  14. Photonic quantum walk in a single beam with twisted light

    CERN Document Server

    Cardano, Filippo; Karimi, Ebrahim; Slussarenko, Sergei; Paparo, Domenico; de Lisio, Corrado; Sciarrino, Fabio; Santamato, Enrico; Marrucci, Lorenzo

    2014-01-01

    Inspired by the classical phenomenon of random walk, the concept of quantum walk has emerged recently as a powerful platform for the dynamical simulation of complex quantum systems, entanglement production and universal quantum computation. Such a wide perspective motivates a renewing search for efficient, scalable and stable implementations of this quantum process. Photonic approaches have hitherto mainly focused on multi-path schemes, requiring interferometric stability and a number of optical elements that scales quadratically with the number of steps. Here we report the experimental realization of a quantum walk taking place in the orbital angular momentum space of light, both for a single photon and for two simultaneous indistinguishable photons. The whole process develops in a single light beam, with no need of interferometers, and requires optical resources scaling linearly with the number of steps. Our demonstration introduces a novel versatile photonic platform for implementing quantum simulations, b...

  15. Quantum interference of independently generated telecom-band single photons

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Monika [Center for Photonic Communication and Computing, Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3112 (United States); Altepeter, Joseph B.; Huang, Yu-Ping; Oza, Neal N. [Center for Photonic Communication and Computing, Department of Electrical Engineering and Computer Science, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3118 (United States); Kumar, Prem [Center for Photonic Communication and Computing, Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3112, USA and Center for Photonic Communication and Computing, Department of Electrical Engineering (United States)

    2014-12-04

    We report on high-visibility quantum interference of independently generated telecom O-band (1310 nm) single photons using standard single-mode fibers. The experimental data are shown to agree well with the results of simulations using a comprehensive quantum multimode theory without the need for any fitting parameter.

  16. 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...

  17. 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...

  18. Experimental demonstration of a predictable single photon source with variable photon flux

    Science.gov (United States)

    Vaigu, Aigar; Porrovecchio, Geiland; Chu, Xiao-Liu; Lindner, Sarah; Smid, Marek; Manninen, Albert; Becher, Christoph; Sandoghdar, Vahid; Götzinger, Stephan; Ikonen, Erkki

    2017-04-01

    We present a predictable single-photon source (SPS) based on a silicon vacancy centre in nanodiamond which is optically excited by a pulsed laser. At an excitation rate of 70~\\text{MHz} the source delivers a photon flux large enough to be measured by a low optical flux detector (LOFD). The directly measured photon flux constitutes an absolute reference. By changing the repetition rate of the pulsed laser, we are able to change the photon flux of our SPS in a controllable way which in turn can act as a reference. The advantage of our method is that it does not require precise knowledge of the source efficiency, but the source is calibrated by the LOFD and can be used for detector responsivity characterizations at the few-photon level.

  19. Environment-induced entanglement with a single photon

    CERN Document Server

    Hor-Meyll, Malena; Borges, Carolina; Aragão, Adriano; Huguenin, José Augusto; Khoury, Antonio; Davidovich, Luiz; 10.1103/PhysRevA.80.042327

    2009-01-01

    We propose an all-optical setup, which couples different degrees of freedom of a single photon, to investigate entanglement generation by a common environment. The two qubits are represented by the photon polarization and Hermite-Gauss transverse modes, while the environment corresponds to the photon path. For an initially two-qubit separable state, the increase of entanglement is analyzed, as the probability of an environment-induced transition ranges from zero to one. An entanglement witness that is invariant throughout the evolution of the system yields a direct measurement of the concurrence of the two-qubit state.

  20. Demonstration of quantum permutation algorithm with a single photon ququart.

    Science.gov (United States)

    Wang, Feiran; Wang, Yunlong; Liu, Ruifeng; Chen, Dongxu; Zhang, Pei; Gao, Hong; Li, Fuli

    2015-06-05

    We report an experiment to demonstrate a quantum permutation determining algorithm with linear optical system. By employing photon's polarization and spatial mode, we realize the quantum ququart states and all the essential permutation transformations. The quantum permutation determining algorithm displays the speedup of quantum algorithm by determining the parity of the permutation in only one step of evaluation compared with two for classical algorithm. This experiment is accomplished in single photon level and the method exhibits universality in high-dimensional quantum computation.

  1. Automated characterization of single-photon avalanche photodiode

    CERN Document Server

    Ghazali, Aina M M; Sauge, Sebastien; Makarov, Vadim

    2012-01-01

    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 uW), dark count rate and photon detection efficiency at different bias voltages. The automated characterization routine is implemented in C++ running on a Linux computer.

  2. 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…

  3. Incoherent photon conversion in selectively infiltrated hollow-core photonic crystal fibers for single photon generation in the near infrared.

    Science.gov (United States)

    Jiang, Ping; Schroeder, Tim; Bath, Michael; Lesnyak, Vladimir; Gaponik, Nikolai; Eychmüller, Alexander; Benson, Oliver

    2012-05-07

    At present, there exist a number of on-demand single photon sources with high emission rates and stability even at room temperature. However, their emission wavelength is restricted to specific transitions in single quantum emitters. Single photon generation in the near infrared, possibly within the telecom band, though most urgently needed, is particularly crucial. In this paper, we suggest an experimental method to convert visible single photons from a defect center in diamond to the near infrared. The conversion relies on efficient absorption by colloidal quantum dots and subsequent Stokes-shifted emission. The desired target wavelength can be chosen almost arbitrarily by selecting quantum dots with a suitable emission spectrum. A hollow core photonic crystal fiber selectively filled with a solution of quantum dots was used to achieve at the same time a single photon absorption probability of near unity and a very high re-collection efficiency of Stokes-shifted fluorescence (theoretically estimated to be 26%). A total conversion efficiency of light of 0.1% is achieved. Experimental strategies to significantly enhance this number are presented.

  4. A bright single-photon source based on a photonic trumpet

    DEFF Research Database (Denmark)

    Munsch, Mathieu; Malik, Nitin S.; Bleuse, Joël

    be brought close to unity with a proper engineering of the wire ends. In particular, a tapering of the top wire end is necessary to achieve a directive far-field emission pattern [1]. Recently, we have realized a single-photon source featuring a needle-like taper. The source efficiency, though record...... top-down fabrication techniques, we have fabricated a single photon source based on this geometry. The trumpet lies on an integrated mirror and embeds a single layer of InAs QDs, located 110 nm above the mirror. We obtain collection efficiencies higher than 40% for a bunch of QDs spread over 35 nm...

  5. On-Chip Single-Photon Sifter

    CERN Document Server

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

    2016-01-01

    Quantum states of light play a pivotal role in modern science[1] and future photonic applications[2]. While impressive progress has been made in their generation and manipulation with high fidelities, the common table-top approach is reaching its limits for practical quantum applications. Since the advent of integrated quantum nanophotonics[3] different material platforms based on III-V nanostructures-, color centers-, and nonlinear waveguides[4-8] as on-chip light sources have been investigated. Each platform has unique advantages and limitations in terms of source properties, optical circuit complexity, and scaling potentials. However, all implementations face major challenges with efficient and tunable filtering of individual quantum states[4], scalable integration and deterministic multiplexing of on-demand selected quantum emitters[9], and on-chip excitation-suppression[10]. Here we overcome all of these challenges with a novel hybrid and scalable nanofabrication approach to generate quantum light on-chi...

  6. Entangling single photons from independently tuned semiconductor nanoemitters.

    Science.gov (United States)

    Sanaka, Kaoru; Pawlis, Alexander; Ladd, Thaddeus D; Sleiter, Darin J; Lischka, Klaus; Yamamoto, Yoshihisa

    2012-09-12

    Quantum communication systems based on nanoscale semiconductor devices is challenged by inhomogeneities from device to device. We address this challenge using ZnMgSe/ZnSe quantum-well nanostructures with local laser-based heating to tune the emission of single impurity-bound exciton emitters in two separate devices. The matched emission in combination with photon bunching enables quantum interference from the devices and allows the postselection of polarization-entangled single photons. The ability to entangle single photons emitted from nanometer-sized sources separated by macroscopic distances provides an essential step for a solid-state realization of a large-scale quantum optical network. This paves the way toward measurement-based entanglement generation between remote electron spins localized at macroscopically separated fluorine impurities.

  7. Probing the Conformations of Single Molecule via Photon Counting Statistics

    CERN Document Server

    Peng, Yonggang; Yang, Chuanlu; Zheng, Yujun

    2014-01-01

    We suggest an approach to detect the conformation of single molecule by using the photon counting statistics. The generalized Smoluchoswki equation is employed to describe the dynamical process of conformational change of single molecule. The resonant trajectories of the emission photon numbers $$ and the Mandel's $Q$ parameter, in the space of conformational coordinates $\\bm{\\mathcal{X}}$ and frequency $\\omega_L$ of external field ($\\bm{\\mathcal{X}}-\\omega_L$ space), can be used to rebuild the conformation of the single molecule. As an example, we consider Thioflavin T molecule. It demonstrates that the results of conformations extracted by employing the photon counting statistics is excellent agreement with the results of {\\it ab initio} computation.

  8. Absolute calibration of fiber-coupled single-photon detector.

    Science.gov (United States)

    Lunghi, Tommaso; Korzh, Boris; Sanguinetti, Bruno; Zbinden, Hugo

    2014-07-28

    We show a setup for characterising the efficiency of a single-photon-detector absolutely and with a precision better than 1%. Since the setup does not rely on calibrated devices and can be implemented with standard-optic components, it can be realised in any laboratory. Our approach is based on an Erbium-Doped-Fiber-Amplifier (EDFA) radiometer as a primary measurement standard for optical power, and on an ultra-stable source of spontaneous emission. As a proof of principle, we characterise the efficiency of an InGaAs/InP single-photon detector. We verified the correctness of the characterisation with independent measurements. In particular, the measurement of the optical power made with the EDFA radiometer has been compared to that of the Federal Institute of Metrology using a transfer power meter. Our approach is suitable for frequent characterisations of high-efficient single-photon detectors.

  9. Absolute calibration of fiber-coupled single-photon detector

    CERN Document Server

    Lunghi, Tommaso; Sanguinetti, Bruno; Zbinden, Hugo

    2014-01-01

    We show a setup for characterising the efficiency of a single-photon-detector absolutely and with a precision better of 1%. Since the setup does not rely on calibrated devices and can be implemented with standard-optic components, it can be realised in any laboratory. Our approach is based on an Erbium-Doped-Fiber-Amplifier (EDFA) radiometer as a primary measurement standard for optical power, and on an ultra-stable source of spontaneous emission. As a proof of principle, we characterise the efficiency of an InGaAs/InP single-photon detector. We verified the correctness of the characterisation with independent measurements. In particular, the measurement of the optical power made with the EDFA radiometer has been compared to that of the Swiss Federal Office of Metrology using a transfer power meter. Our approach is suitable for frequent characterisations of high-efficient single-photon detectors.

  10. 99% efficiency in collecting photons from a single emitter

    CERN Document Server

    Chen, Xue-Wen; Sandoghdar, Vahid

    2011-01-01

    In Nature Photonics 5, 166 (2011), we reported on a planar dielectric antenna that achieved 96% efficiency in collecting the photons emitted by a single molecule. In that work the transition dipole moment of the molecule was set perpendicular to the antenna plane. Here, we present an extension of that scheme that reaches collection efficiencies beyond 99% for emitters with arbitrarily oriented dipole moments. Our work opens important doors in a wide range of contexts including quantum optics, quantum metrology, nano-analytics, and biophysics. In particular, we provide antenna parameters to realize ultrabright single-photon sources in high-index materials such as semiconductor quantum dots and color centers in diamond, as well as sensitive detection of single molecules in nanofluidic devices.

  11. 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...

  12. Avalanche photodiodes and quenching circuits for single-photon detection

    Science.gov (United States)

    Cova, S.; Ghioni, M.; Lacaita, A.; Samori, C.; Zappa, F.

    1996-04-01

    Avalanche photodiodes, which operate above the breakdown voltage in Geiger mode connected with avalanche-quenching circuits, can be used to detect single photons and are therefore called single-photon avalanche diodes SPAD's. Circuit configurations suitable for this operation mode are critically analyzed and their relative merits in photon counting and timing applications are assessed. Simple passive-quenching circuits (PQC's), which are useful for SPAD device testing and selection, have fairly limited application. Suitably designed active-quenching circuits (AQC's) make it possible to exploit the best performance of SPAD's. Thick silicon SPAD's that operate at high voltages (250-450 V) have photon detection efficiency higher than 50% from 540-to 850-nm wavelength and still approximately 3% at 1064 nm. Thin silicon SPAD's that operate at low voltages (10-50 V) have 45% efficiency at 500 nm, declining to 10% at 830 nm and to as little as 0.1% at 1064 nm. The time resolution achieved in photon timing is 20 ps FWHM with thin SPAD's; it ranges from 350 to 150 ps FWHM with thick SPAD's. The achieved minimum counting dead time and maximum counting rate are 40 ns and 10 Mcps with thick silicon SPAD's, 10 ns and 40 Mcps with thin SPAD's. Germanium and III-V compound semiconductor SPAD's extend the range of photon-counting techniques in the near-infrared region to at least 1600-nm wavelength.

  13. Investigation of Hamamatsu H8500 phototubes as single photon detectors

    CERN Document Server

    Hoek, M; Mirazita, M; Montgomery, R A; Orlandi, A; Pereira, S Anefalos; Pisano, S; Rossi, P; Viticchiè, A; Witchger, A

    2014-01-01

    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 407.2nm 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.

  14. Optimizing optical Bragg scattering for single-photon frequency conversion

    CERN Document Server

    Lefrancois, Simon; Eggleton, Benjamin J

    2014-01-01

    We develop a systematic theory for optimising single-photon frequency conversion using optical Bragg scattering. The efficiency and phase-matching conditions for the desired Bragg scattering conversion as well as spurious scattering and modulation instability are identified. We find that third-order dispersion can suppress unwanted processes, while dispersion above the fourth order limits the maximum conversion efficiency. We apply the optimisation conditions to frequency conversion in highly nonlinear fiber, silicon nitride waveguides and silicon nanowires. Efficient conversion is confirmed using full numerical simulations. These design rules will assist the development of efficient quantum frequency conversion between multicolour single photon sources for integration in complex quantum networks.

  15. Nanofabrication of Plasmonic Circuits Containing Single Photon Sources

    DEFF Research Database (Denmark)

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

    2017-01-01

    -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...... is achieved, indicating significant mode confinement. Finally, we demonstrate routing of single plasmons with DLSPPW-based directional couplers, revealing the potential of our approach for on-chip realization of quantum optical networks....

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

    CERN Document Server

    Chen, Yuntian; 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.

  17. Design and simulations of highly efficient single-photon sources

    DEFF Research Database (Denmark)

    Gregersen, Niels; de Lasson, Jakob Rosenkrantz; Mørk, Jesper

    The realization of the highly-efficient single-photon source represents not only an experimental, but also a numerical challenge. We will present the theory of the waveguide QED approach, the design challenges and the current limitations. Additionally, the important numerical challenges in the si......The realization of the highly-efficient single-photon source represents not only an experimental, but also a numerical challenge. We will present the theory of the waveguide QED approach, the design challenges and the current limitations. Additionally, the important numerical challenges...

  18. 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....

  19. 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...

  20. 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.

  1. Single photon in hierarchical architecture for physical reinforcement learning: Photon intelligence

    CERN Document Server

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

    2016-01-01

    Understanding and using natural processes for intelligent functionalities, referred to as natural intelligence, has recently attracted interest from a variety of fields, including post-silicon computing for artificial intelligence and decision making in the behavioural sciences. In a past study, we successfully used the wave-particle duality of single photons to solve the two-armed bandit problem, which constitutes the foundation of reinforcement learning and decision making. In this study, we propose and confirm a hierarchical architecture for single-photon-based reinforcement learning and decision making that verifies the scalability of the principle. Specifically, the four-armed bandit problem is solved given zero prior knowledge in a two-layer hierarchical architecture, where polarization is autonomously adapted in order to effect adequate decision making using single-photon measurements. In the hierarchical structure, the notion of layer-dependent decisions emerges. The optimal solutions in the coarse la...

  2. Single-photon switch: Controllable scattering of photons inside a one-dimensional resonator waveguide

    Science.gov (United States)

    Zhou, L.; Gong, Z. R.; Liu, Y. X.; Sun, C. P.; Nori, F.

    2010-03-01

    We analyze the coherent transport of a single photon, which propagates in a one-dimensional coupled-resonator waveguide and is scattered by a controllable two-level system located inside one of the resonators of this waveguide. Our approach, which uses discrete coordinates, unifies low and high energy effective theories for single-photon scattering. We show that the controllable two-level system can behave as a quantum switch for the coherent transport of a single photon. This study may inspire new electro-optical single-photon quantum devices. We also suggest an experimental setup based on superconducting transmission line resonators and qubits. References: L. Zhou, Z.R. Gong, Y.X. Liu, C.P. Sun, F. Nori, Controllable scattering of photons inside a one-dimensional resonator waveguide, Phys. Rev. Lett. 101, 100501 (2008). L. Zhou, H. Dong, Y.X. Liu, C.P. Sun, F. Nori, Quantum super-cavity with atomic mirrors, Phys. Rev. A 78, 063827 (2008).

  3. Producing high fidelity single photons with optimal brightness

    CERN Document Server

    Laiho, K; Silberhorn, Ch

    2009-01-01

    Parametric down-conversion (PDC) offers the possibility to control the fabrication of non-Gaussian states such as Fock states. However, in conventional PDC sources energy and momentum conservation introduce strict frequency and photon number correlations, which impact the fidelity of the prepared state. In our work we optimize the preparation of single-photon Fock state from the emission of waveguided PDC via spectral filtering. We study the effect of correlations via photon number resolving detection and quantum interference. Our measurements show how the reduction of mixness due to filtering can be evaluated. Interfering the prepared photon with a coherent state we establish an experimentally measured fidelity of the produced target state of 78%.

  4. Single photon imaging at ultra-high resolution

    Science.gov (United States)

    Bellazzini, R.; Spandre, G.; Minuti, M.; Brez, A.; Baldini, L.; Latronico, L.; Omodei, N.; Sgrò, C.; Bregeon, J.; Razzano, M.; Pinchera, M.; Tremsin, A.; McPhate, J.; Vallerga, J. V.; Siegmund, O.

    2008-06-01

    We present a detection system capable of imaging both single photon/positive ion and multiple coincidence photons/positive ions with extremely high spatial resolution. In this detector the photoelectrons excited by the incoming photons are multiplied by microchannel plate(s) (MCP). The process of multiplication is spatially constrained within an MCP pore, which can be as small as 4 μm for commercially available MCPs. An electron cloud originated by a single photoelectron is then encoded by a pixellated custom analog ASIC consisting of 105 K charge sensitive pixels of 50 μm in size arranged on a hexagonal grid. Each pixel registers the charge with an accuracy of electrons rms. Computation of the event centroid from the readout charges results in an accurate event position. A large number of simultaneous photons spatially separated by ˜0.4 mm can be detected simultaneously allowing multiple coincidence operation for the experiments where a large number of incoming photons/positive ions have to be detected simultaneously. The experimental results prove that the spatial resolution of the readout system itself is ˜3 μm FWHM enabling detection resolution better than 6 μm for the small pore MCPs. An attractive feature of the detection system is its capability to register the timing of each incoming photon/positive ion (in single photon detection mode) or of the first incoming particle (for the multiple coincidence detection) with an accuracy of ˜130 ps FWHM. There is also virtually no dark count noise in the detection system making it suitable for low count rate applications.

  5. Photonic nanowire-based single-photon source with polarization control

    CERN Document Server

    Gregersen, Niels

    2016-01-01

    This document describes a modal method for optical simulations of structures with elliptical cross sections and its application to the design of the photonic nanowire (NW)-based single-photon source (SPS). The work was carried out in the framework of the EMRP SIQUTE project ending May 31st 2016. The document summarizes the new method used to treat the elliptical cross section in an efficient manner and additionally presents design parameters for the photonic NW SPS with elliptical cross section for polarization control. The document does not introduce the new method and the elliptical photonic NW SPS design in the context of existing literature but instead dives directly into the equations. Additionally, the document assumes that the reader possess expert knowledge of general modal expansion techniques. The presented formalism does not implement Li's factorization rules nor the recently proposed open boundary geometry formalism with fast convergence towards the open geometry limit but instead relies on (older...

  6. Controlling the quantum state of a single photon emitted from a single polariton

    Energy Technology Data Exchange (ETDEWEB)

    Stanojevic, Jovica; Parigi, Valentina; Bimbard, Erwan; Tualle-Brouri, Rosa; Ourjoumtsev, Alexei; Grangier, Philippe [Laboratoire Charles Fabry, Institut d' Optique, CNRS, Universite Paris-Sud, Campus Polytechnique, RD 128, FR-91127 Palaiseau cedex (France)

    2011-11-15

    We investigate in detail the optimal conditions for a high fidelity transfer from a single-polariton state to a single-photon state and subsequent homodyne detection of the single photon. We assume that, using various possible techniques, the single polariton has initially been stored as a spin-wave grating in a cloud of cold atoms inside a low-finesse cavity. This state is then transferred to a single-photon optical pulse using an auxiliary beam. We optimize the retrieval efficiency and determine the mode of the local oscillator that maximizes the homodyne efficiency of such a photon. We find that both efficiencies can have values close to one in a large region of experimental parameters.

  7. Controlling the quantum state of a single photon emitted from a single polariton

    CERN Document Server

    Stanojevic, Jovica; Bimbard, Erwan; Tualle-Brouri, Rosa; Ourjoumtsev, Alexei; Grangier, Philippe; 10.1103/PhysRevA.84.053830

    2012-01-01

    We investigate in detail the optimal conditions for a high fidelity transfer from a single-polariton state to a single-photon state and subsequent homodyne detection of the single photon. We assume that, using various possible techniques, the single polariton has initially been stored as a spin-wave grating in a cloud of cold atoms inside a low-finesse cavity. This state is then transferred to a single-photon optical pulse using an auxiliary beam. We optimize the retrieval efficiency and determine the mode of the local oscillator that maximizes the homodyne efficiency of such a photon. We find that both efficiencies can have values close to one in a large region of experimental parameters.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. Theory on single molecule_photon cryocooler

    Institute of Scientific and Technical Information of China (English)

    QIN; Weiping

    2001-01-01

    [1]Pringsheim, P., Zwei Bemerkungen über den Unterschied von Lumineszenz_ und Temperaturstrahlung, Z. Phys., 929, 57(8): 739.[2]Djeu, N., Whitney, W. T., Laser cooling by spontaneous anti_Stokes scattering, Phys. Rev. Lett., 98, 46(4): 236.[3]Epstein, I., Buchwald, M. I., Edwards, B. C. et al., Observation of laser_induced fluorescent cooling of a solid, Nature, 995, 377(2): 500.[4]Clark, J. L., Rumbles, G., Laser cooling in the condensed phase by frequency up_conversion, Phys. Rev. Lett., 996, 76(2): 2037.[5]Mungan, C. E., Buchwald, M. I., Edwards, B. C. et al., Laser cooling of a solid by 6 K starting from room temperature, Phys. Rev. Lett., 997, 78(6): 030.[6]Luo, X., Eisaman, M. D., Gosnell, T. R., Laser cooling of a solid by 2K starting from room temperature, Opt. Lett., 998, 23(8): 639.[7]Gosnell, T. R., Laser cooling of a solid by 2K starting from room temperature, Optics Let., 999, 24(5): 04.[8]Epstein, I., Buchwald, M. I., Edwards, B. C. et al., The Los Alamos solid_state optical refrigerator, Cryocoolers 9, New York: Plenum, 997, 68—686.[9]Qin Weiping, Zhang Jiahua, Huang Shihua, Laser_induced anti_Stokes fluorescent cooling, Physics (in Chinese), 998, 27(6): 323.[10]Christiansen, W. H., Hertzberg, A., Gasdynamic lasers and photon machines, Proc. IEEE, 973, 6(8): 060.[11]Qin Weiping, Zhang Jiahua, Huang Shihua, Study on the fluorescent cooling by energy transfer within in homogenous line shape in solids, Acta Physica Sinica (in Chinese), 998, 47(8): 397.[12]Qin Weiping, Zhang Jiahua, Chen Baojiu et al., Two basic mechanism in anti_Stokes fluorescent cooling of solids, Chinese Journal of Luminescence, 999, 20(2): 26.[13]Fournier, J. T., Bartram, R. H., Inhomogeneous broadening of the optical spectra of Yb3+in phosphate glass, J. Phys. Chem. Solids, 970, 3(2): 265.

  13. Weaving single photon imaging into new drug development.

    Science.gov (United States)

    Mozley, P David

    2005-01-01

    The specific aim of this review is to assess the potential contribution of single photon emitting radiopharmaceutical technologies to new drug development. For each phase of therapeutic drug development, published literature was sought that shows single photon emitters can add value by quantifying pharmacokinetics, visualizing mechanisms of drug action, estimating therapeutic safety indices, or measuring dose-dependent pharmacodynamic effects. Not any published reports were found that describe using nuclear medicine techniques to help manage the progress of a new drug development program. As a consequence, most of the case in favor of weaving single photon imaging into the process had to be built on extrapolations from studies that showed feasibility post hoc. The strongest evidence of potential value was found for drug candidates that hope to influence diseases characterized by cell proliferation or cell death, particularly in the fields of oncology, cardiology, nephrology, and inflammation. Receptor occupancy studies were observed to occasionally offer unique advantages over analogous studies with positron emission tomography (PET). Enough hard data sets were found to justify the costs of using single photon imaging in a variety of new drug development paradigms.

  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. State-independent quantum contextuality with single photons

    CERN Document Server

    Amselem, Elias; Bourennane, Mohamed; Cabello, Adan

    2009-01-01

    Bell's theorem states that quantum predictions cannot be reproduced with hidden variable theories satisfying locality. The Kochen-Specker theorem states that quantum mechanics cannot be reproduced with non-contextual hidden variables. The result of a measurement is non-contextual when it is not affected by other compatible measurements being carried out on the same individual system. While Bell's theorem applies only to entangled states of composite systems, a distinguishing feature of the Kochen-Specker theorem is that it is valid for any quantum state, entangled or not, of any system, even for single systems. We present the first experimental state-independent violation of an inequality for non-contextual theories on single particles in the spirit of the original Kochen-Specker theorem. The tested inequality involves correlations between results of sequential compatible measurements on single photons. We show that 20 different single-photon states, ranging from states with maximal internal entanglement to m...

  16. Single-Photon Source for Quantum Information Based on Single Dye Molecule Fluorescence in Liquid Crystal Host

    Energy Technology Data Exchange (ETDEWEB)

    Lukishova, S.G.; Knox, R.P.; Freivald, P.; McNamara, A.; Boyd, R.W.; Stroud, Jr., C.R.; Schmid, A.W.; Marshall, K.L.

    2006-08-18

    This paper describes a new application for liquid crystals: quantum information technology. A deterministically polarized single-photon source that efficiently produces photons exhibiting antibunching is a pivotal hardware element in absolutely secure quantum communication. Planar-aligned nematic liquid crystal hosts deterministically align the single dye molecules which produce deterministically polarized single (antibunched) photons. In addition, 1-D photonic bandgap cholesteric liquid crystals will increase single-photon source efficiency. The experiments and challenges in the observation of deterministically polarized fluorescence from single dye molecules in planar-aligned glassy nematic-liquid-crystal oligomer as well as photon antibunching in glassy cholesteric oligomer are described for the first time.

  17. 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.

  18. Single particle detection in CMOS compatible photonic crystal nanobeam cavities.

    Science.gov (United States)

    Quan, Qimin; Floyd, Daniel L; Burgess, Ian B; Deotare, Parag B; Frank, Ian W; Tang, Sindy K Y; Ilic, Rob; Loncar, Marko

    2013-12-30

    We report the label-free detection of single particles using photonic crystal nanobeam cavities fabricated in silicon-on-insulator platform, and embedded inside microfluidic channels fabricated in poly-dimethylsiloxane (PDMS). Our system operates in the telecommunication wavelength band, thus leveraging the widely available, robust and tunable telecom laser sources. Using this approach, we demonstrated the detection of polystyrene nanoparticles with dimensions down to 12.5nm in radius. Furthermore, binding events of a single streptavidin molecule have been observed.

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

    CERN Document Server

    Björk, Gunnar; Andersen, Ulrik L

    2011-01-01

    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 uses only classical resources, namely coherent states, a Kerr non-linearity, and a two-level atom.

  20. Superconducting single-photon detectors for integrated quantum optics

    Energy Technology Data Exchange (ETDEWEB)

    Kahl, Oliver

    2016-01-29

    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.

  1. Heterodyne spectroscopy with superconducting single-photon detector

    Science.gov (United States)

    Lobanov, Yu. V.; Shcherbatenko, M. L.; Semenov, A. V.; Kovalyuk, V. V.; Korneev, A. A.; Goltsman, G. N.

    2016-12-01

    We demonstrate successful operation of a Superconducting Single Photon Detector (SSPD) as the core element in a heterodyne receiver. Irradiating the SSPD by both a local oscillator power and signal power simultaneously, we observed beat signal at the intermediate frequency of a few MHz. Gain bandwidth was found to coincide with the detector single pulse width, where the latter depends on the detector kinetic inductance, determined by the superconducting nanowire length.

  2. Feasibility of detecting single atoms using photonic bandgap cavities

    OpenAIRE

    Lev, Benjamin; Srinivasan, Kartik; Barclay, Paul; Painter, Oskar; Mabuchi, Hideo

    2004-01-01

    We propose an atom-cavity chip that combines laser cooling and trapping of neutral atoms with magnetic microtraps and waveguides to deliver a cold atom to the mode of a fiber taper coupled photonic bandgap (PBG) cavity. The feasibility of this device for detecting single atoms is analyzed using both a semi-classical treatment and an unconditional master equation approach. Single-atom detection seems achievable in an initial experiment involving the non-deterministic delivery of weakly trapped...

  3. Single-photon superradiance from a quantum dot

    DEFF Research Database (Denmark)

    Tighineanu, Petru; Daveau, Raphaël Sura; Lehmann, Tau Bernstorff

    2016-01-01

    We report on the observation of single-photon superradiance from an exciton in a semiconductor quantum dot. The confinement by the quantum dot is strong enough for it to mimic a two-level atom, yet sufficiently weak to ensure superradiance. The electrostatic interaction between the electron...... temperature of our cryostat and may lead to oscillator strengths above 1000 from a single quantum emitter at optical frequencies....

  4. Heterodyne spectroscopy with superconducting single-photon detector

    Directory of Open Access Journals (Sweden)

    Lobanov Yu.V.

    2017-01-01

    Full Text Available We demonstrate successful operation of a Superconducting Single Photon Detector (SSPD as the core element in a heterodyne receiver. Irradiating the SSPD by both a local oscillator power and signal power simultaneously, we observed beat signal at the intermediate frequency of a few MHz. Gain bandwidth was found to coincide with the detector single pulse width, where the latter depends on the detector kinetic inductance, determined by the superconducting nanowire length.

  5. Research on high-speed single photon detector

    Science.gov (United States)

    Wang, Chao; Yang, Hao; Wang, Di; Ma, Haiqiang; Luo, Kaihong; Sun, Zhibin; Zhai, Guangjie

    2010-10-01

    Single-photon detector based on an InGaAs avalanche photodiode is one of hot research on the quantum photon, and is one of the key technologies on quantum communication and quantum image. It is widely used in applications as high sensitive photon spectrum, high speed optic measurement and so on. A suitable delay and comparator with latch function circuit are used to prevent positive and negative transient pulses from influencing the detection of true photon induced avalanches. A dead time modulation feedback control circuit decreases the after-pulse. Especially, ECL difference circuit is the key of high speed single photon detector. In addition, the detector uses the hot tube fan-cooling method. From the performance test, the lowest temperature reaches -62°C, the minimum gate pulse width is 2ns (Full-Width-Half-Max, FWHM) and the dark counter rate is 2.5×10-6 ns-1 with a detection rate of 10MHz when the quantum efficiency is more than 10%.

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

    NARCIS (Netherlands)

    van Oosten, D.; 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

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

    NARCIS (Netherlands)

    van Oosten, D.; 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 shi

  8. High-efficiency single-photon source: The photonic wire geometry

    DEFF Research Database (Denmark)

    Claudon, J.; Bazin, Maela; Malik, Nitin S.

    2009-01-01

    We present a single-photon-source design based on the emission of a quantum dot embedded in a semiconductor (GaAs) nanowire. The nanowire ends are engineered (efficient metallic mirror and tip taper) to reach a predicted record-high collection efficiency of 90% with a realistic design. Preliminary...

  9. 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...

  10. Spectral density matrix of a single photon measured.

    Science.gov (United States)

    Wasilewski, Wojciech; Kolenderski, Piotr; Frankowski, Robert

    2007-09-21

    We propose and demonstrate a method for measuring the spectral density matrix of a single photon pulse. The method is based on registering Hong-Ou-Mandel interference between a photon to be measured and a pair of attenuated and suitably delayed laser pulses described by a known spectral amplitude. The density matrix is retrieved from a two-dimensional interferogram of coincidence counts. The method has been implemented for a type-I down-conversion source, pumped by ultrashort laser pulses. The experimental results agree well with a theoretical model which takes into account the temporal as well as spatial effects in the source.

  11. Spectral density matrix of a single photon measured

    CERN Document Server

    Wasilewski, W; Frankowski, R; Wasilewski, Wojciech; Kolenderski, Piotr; Frankowski, Robert

    2007-01-01

    We propose and demonstrate a method for measuring the spectral density matrix of a single photon pulse. The method is based on registering Hong-Ou-Mandel interference between photon to be measured and a pair of attenuated and suitably delayed laser pulses described by a known spectral amplitude. The density matrix is retrieved from a two-dimensional interferogram of coincidence counts. The method has been implemented for a type-I downconversion source, pumped by ultrashort laser pulses. The experimental results agree well with a theoretical model which takes into account the temporal as well as spatial effects in the source.

  12. On-Chip Detection of Entangled Photons by Scalable Integration of Single-Photon Detectors

    CERN Document Server

    Najafi, Faraz; Harris, Nicholas; Bellei, Francesco; Dane, Andrew; Lee, Catherine; Kharel, Prashanta; Marsili, Francesco; Assefa, Solomon; Berggren, Karl K; Englund, Dirk

    2014-01-01

    Photonic integrated circuits (PICs) have emerged as a scalable platform for complex quantum technologies using photonic and atomic systems. A central goal has been to integrate photon-resolving 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 timing jitter, nanosecond-scale reset time, and sensitivity from the visible to the mid-infrared spectrum. However, while single SNSPDs have been incorporated into individual waveguides, the system efficiency of multiple SNSPDs in one photonic circuit has been limited below 0.2% due to low device yield. Here we introduce a micrometer-scale flip-chip process that enables scalable integration of SNSPDs on a range of PICs. Ten low-jitter detectors were integrated on one PIC with 100% device yield. With an average system efficiency beyond 10% for multiple SNSPDs on one PIC, we demonstrate h...

  13. 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.)

  14. Controlled single-photon emission from a single trapped two-level atom.

    Science.gov (United States)

    Darquié, B; Jones, M P A; Dingjan, J; Beugnon, J; Bergamini, S; Sortais, Y; Messin, G; Browaeys, A; Grangier, P

    2005-07-15

    By illuminating an individual rubidium atom stored in a tight optical tweezer with short resonant light pulses, we created an efficient triggered source of single photons with a well-defined polarization. The measured intensity correlation of the emitted light pulses exhibits almost perfect antibunching. Such a source of high-rate, fully controlled single-photon pulses has many potential applications for quantum information processing.

  15. A review on single photon sources in silicon carbide

    Science.gov (United States)

    Lohrmann, A.; Johnson, B. C.; McCallum, J. C.; Castelletto, S.

    2017-03-01

    This paper summarizes key findings in single-photon generation from deep level defects in silicon carbide (SiC) and highlights the significance of these individually addressable centers for emerging quantum applications. Single photon emission from various defect centers in both bulk and nanostructured SiC are discussed as well as their formation and possible integration into optical and electrical devices. The related measurement protocols, the building blocks of quantum communication and computation network architectures in solid state systems, are also summarized. This includes experimental methodologies developed for spin control of different paramagnetic defects, including the measurement of spin coherence times. Well established doping, and micro- and nanofabrication procedures for SiC may allow the quantum properties of paramagnetic defects to be electrically and mechanically controlled efficiently. The integration of single defects into SiC devices is crucial for applications in quantum technologies and we will review progress in this direction.

  16. 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.

  17. Few-photon coherent nonlinear optics with a single molecule

    CERN Document Server

    Maser, Andreas; Utikal, Tobias; Götzinger, Stephan; Sandoghdar, Vahid

    2015-01-01

    The pioneering experiments of linear spectroscopy were performed using flames in the 1800s, but nonlinear optical measurements had to wait until lasers became available in the twentieth century. Because the nonlinear cross section of materials is very small, usually macroscopic bulk samples and pulsed lasers are used. Numerous efforts have explored coherent nonlinear signal generation from individual nanoparticles or small atomic ensembles with millions of atoms. Experiments on a single semiconductor quantum dot have also been reported, albeit with a very small yield. Here, we report on coherent nonlinear spectroscopy of a single molecule under continuous-wave single-pass illumination, where efficient photon-molecule coupling in a tight focus allows switching of a laser beam by less than a handful of pump photons nearly resonant with the sharp molecular transition. Aside from their fundamental importance, our results emphasize the potential of organic molecules for applications such as quantum information pro...

  18. Performance limits of a single photon counting pixel system

    Energy Technology Data Exchange (ETDEWEB)

    Chmeissani, M.; Mikulec, B. E-mail: bettina.mikulec@cern.ch

    2001-03-11

    X-ray imaging using hybrid pixel detectors in single photon counting mode is a relatively recent and exciting development. The photon counting mode implies that each pixel has a threshold in energy above which a hit is recorded. Sharing of charge between adjacent pixels would therefore lead to a loss of registered hits and for medical imaging applications to a higher patient dose. This explains why the demand for high spatial resolution and consequently small pixel sizes (<100 {mu}m) motivates the Medipix2 collaboration to study the effects of charge sharing between pixels on system performance. Two different simulation codes are used to simulate the energy loss inside the detector and the charge transport towards the pixel electrodes. The largest contribution to the lateral spreading of charge comes from diffusion and can result in a considerable loss of detection efficiency in photon counting systems for small pixel sizes.

  19. Single Photon studies in ATLAS with Run 2 dataset

    CERN Document Server

    Aparisi Pozo, Javier Alberto; Solans Sanchez, Carlos; CERN. Geneva. EP Department

    2016-01-01

    We present a performance study of photon reconstruction within the Higgs working group of the ATLAS experiment. The analysis use a data sample of proton-proton collisions at center-of-mass energy of $\\sqrt{s} = 13~TeV$, recorded with the ATLAS detector at the LHC in 2015+2016, corresponding to a total integrated luminosity of 14.5 $fb^{-1}$ (at the moment). The performance of electron and photon reconstruction plays a critical role in the reach of many analysis, including $H\\rightarrow \\gamma \\gamma$ and $H\\rightarrow 4l$ concerning Higgs searches. This work is a study of single photon conversions with the ATLAS detector.

  20. 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.

  1. Detection of single photons with THickGEM-based counters

    Energy Technology Data Exchange (ETDEWEB)

    Alexeev, M. [INFN, Sezione di Torino and University of East Piemonte, Alessandria (Italy); Barbosa, F. [I3N - Physics Department, University of Aveiro (Portugal); Birsa, R. [INFN, Sezione di Trieste, Trieste (Italy); Bradamante, F.; Bressan, A. [INFN, Sezione di Trieste and University of Trieste, Trieste (Italy); Chiosso, M. [INFN, Sezione di Torino and University of Torino, Torino (Italy); Ciliberti, P. [INFN, Sezione di Trieste and University of Trieste, Trieste (Italy); Dalla Torre, S. [INFN, Sezione di Trieste, Trieste (Italy); Denisov, O. [INFN, Sezione di Torino, Torino (Italy); Duic, V. [INFN, Sezione di Trieste and University of Trieste, Trieste (Italy); Ferrero, A. [INFN, Sezione di Torino and University of Torino, Torino (Italy); Finger, M.; Finger, M. [Charles University, Praga (Czech Republic); JINR, Dubna (Russian Federation); Fischer, H. [Universitaet Freiburg, Physikalisches Institut, Freiburg (Germany); Giorgi, M. [INFN, Sezione di Trieste and University of Trieste, Trieste (Italy); Gobbo, B.; Gregori, M. [INFN, Sezione di Trieste, Trieste (Italy); Heinsius, F.H.; Herrmann, F.; Koenigsmann, K. [Universitaet Freiburg, Physikalisches Institut, Freiburg (Germany); and others

    2012-12-11

    Cherenkov imaging counters requiring large photosensitive areas, the capability to stand high rates and to operate in magnetic field environments could benefit from the use of photon detectors based on THick Gaseous Electron Multiplier (THGEM) coupled to a solid state CsI photo-cathode. A systematic study of the THGEM detector response as a function of its geometrical parameters and electrodes' applied voltage has been performed. Dedicated electrostatic calculations to optimize the detector design have been accomplished. Data obtained from small photon detector prototypes operating in single photon detection mode are presented and discussed. In particular the key aspect of photo-electron extraction from the photo-cathode surface is investigated via the timing spectrum response of the detector for different electric field conditions at the photo-cathode: a comparison of the measured time distributions and the simulation results is illustrated.

  2. Fragmentation dynamics of ammonia cluster ions after single photon ionisation

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, E.; Vries, J. de; Steger, H.; Menzel, C.; Kamke, W.; Hertel, I.V. (Freiburg Univ. (Germany, F.R.). Fakultaet fuer Physik Freiburg Univ. (Germany, F.R.). Freiburger Materialforschungszentrum)

    1991-01-01

    A reflecting time of flight mass spectrometer (RETOF) is used to study unimolecular and collision induced fragmentation of ammonia cluster ions. Synchrotron radiation from the BESSY electron storage ring is used in a range of photon energies from 9.08 up to 17.7 eV for single photon ionisation of neutral clusters in a supersonic beam. The threshold photoelectron photoion coincidence technique (TPEPICO) is used to define the energy initially deposited into the cluster ions. Metastable unimolecular decay ({mu}s range) is studied using the RETOF's capacity for energy analysis. Under collision free conditions the by far most prominent metastable process is the evaporation of one neutral NH{sub 3} monomer from protonated clusters (NH{sub 3}){sub x}NH{sub 4}{sup +}. Abundance of homogeneous vs. protonated cluster ions and of metastable fragments are reported as a function of photon energy and cluster size up to n=10. (orig.).

  3. 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 ...... of the quasi-Gaussian emission mode, but with inverted TPW where the apex is the cone's base, leads to even larger efficiencies. In addition, these inverted TPWs make the electric pumping of the emitters compatible with these large efficiencies....

  4. Femtosecond three-photon excitation and single-photon timing detection of α-NPO fluorescence

    Science.gov (United States)

    Volkmer, A.; Hatrick, D. A.; Bai, Y.; Birch, D. J. S.

    1997-04-01

    We demonstrate the application of three-photon excitation to fluorescence probe studies using time-correlated single-photon counting (TCSPC). By exciting with 120 fs Ti:sapphire laser pulses at 800 nm we have observed fluorescence emission from the scintillator 2-(1-napthyl)-5-phenyloxazole (α-NPO) in solutions and small unilamellar vesicles (SUVs) of L-α-dipalmitoylphosphatidylcholine (DPPC). In SUVs the time-resolved excimer emission and fluorescence anisotropy are consistent with a heterogeneous distribution of α-NPO molecules between isolated sites and ground state clusters in a similar manner to that which we reported previously for 2,5-diphenyloxazole (PPO).

  5. 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.

  6. Avalanche photodiodes and quenching circuits for single-photon detection.

    Science.gov (United States)

    Cova, S; Ghioni, M; Lacaita, A; Samori, C; Zappa, F

    1996-04-20

    Avalanche photodiodes, which operate above the breakdown voltage in Geiger mode connected with avalanche-quenching circuits, can be used to detect single photons and are therefore called singlephoton avalanche diodes SPAD's. Circuit configurations suitable for this operation mode are critically analyzed and their relative merits in photon counting and timing applications are assessed. Simple passive-quenching circuits (PQC's), which are useful for SPAD device testing and selection, have fairly limited application. Suitably designed active-quenching circuits (AQC's) make it possible to exploit the best performance of SPAD's. Thick silicon SPAD's that operate at high voltages (250-450 V) have photon detection efficiency higher than 50% from 540- to 850-nm wavelength and still ~3% at 1064 nm. Thin silicon SPAD's that operate at low voltages (10-50 V) have 45% efficiency at 500 nm, declining to 10% at 830 nm and to as little as 0.1% at 1064 nm. The time resolution achieved in photon timing is 20 ps FWHM with thin SPAD's; it ranges from 350 to 150 ps FWHM with thick SPAD's. The achieved minimum counting dead time and maximum counting rate are 40 ns and 10 Mcps with thick silicon SPAD's, 10 ns and 40 Mcps with thin SPAD's. Germanium and III-V compound semiconductor SPAD's extend the range of photon-counting techniques in the near-infrared region to at least 1600-nm wavelength.

  7. Quantum Frequency Translation of Single-Photon States in Photonic Crystal Fiber

    CERN Document Server

    McGuinness, H J; McKinstrie, C J; Radic, S

    2010-01-01

    We experimentally demonstrate frequency translation of a nonclassical optical field via the Bragg scattering four-wave mixing process in a photonic crystal fiber (PCF). The high nonlinearity and the ability to control dispersion in PCF enable efficient translation between photon channels within the visible to-near-infrared spectral range, useful in quantum networks. Heralded single photons at 683 nm were translated to 659 nm with an efficiency of $28.6 \\pm 2.2$ percent. Second-order correlation measurements on the 683-nm and 659-nm fields yielded $g^{(2)}_{683}(0) = 0.21 \\pm 0.02$ and $g^{(2)}_{659}(0) = 0.19 \\pm 0.05$ respectively, showing the nonclassical nature of both fields.

  8. Quantum frequency translation of single-photon states in a photonic crystal fiber.

    Science.gov (United States)

    McGuinness, H J; Raymer, M G; McKinstrie, C J; Radic, S

    2010-08-27

    We experimentally demonstrate frequency translation of a nonclassical optical field via four-wave mixing (Bragg-scattering process) in a photonic crystal fiber (PCF). The high nonlinearity and the ability to control dispersion in PCF enable efficient translation between nearby photon channels within the visible to-near-infrared spectral range, useful in quantum networks. Heralded single photons at 683 nm were translated to 659 nm with an efficiency of 28.6±2.2 percent. Second-order correlation measurements on the 683- and 659-nm fields yielded g(683)(2) (0)=0.21±0.02 and g(659)(2) (0)=0.19±0.05, respectively, showing the nonclassical nature of both fields.

  9. Research in absolute calibration of single photon detectors by means of correlated photons

    Institute of Scientific and Technical Information of China (English)

    Yu Feng; Xiaobing Zheng; Jianjun Li; Wei Zhang

    2006-01-01

    There are two general methods in radiometric calibration of detectors, one is based on radiation sources and the other based on detectors. Because the two methods need to establish a primary standard of high precision and a transfer chain, precision of the standard will be reduced by extension of the chain. A new calibration method of detectors can be realized by using correlated photons generated in spontaneous parametric down-conversion (SPDC) effect of nonlinear crystal, without needing transfer chain. Using 351.1-nm output of a tunable laser to pump β-barium borate (BBO) crystal, an absolute calibration experimental system of single photon detectors based on correlated photons is performed. The quantum efficiency of photomultiplier (PMT) at 702.2 nm is measured by the setup. Advantages of this method over traditional methods are also pointed out by comparison.

  10. 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

  11. Weak Value Amplification of a Post-Selected Single Photon

    Science.gov (United States)

    Hallaji, Matin

    Weak value amplification (WVA) is a measurement technique in which the effect of a pre- and post-selected system on a weakly interacting probe is magnified. In this thesis, I present the first experimental observation of WVA of a single photon. We observed that a signal photon --- sent through a polarization interferometer and post-selected by photodetection in the almost-dark port --- can act like eight photons. The effect of this single photon is measured as a nonlinear phase shift on a separate laser beam. The interaction between the two is mediated by a sample of laser- cooled 85Rb atoms. Electromagnetically induced transparency (EIT) is used to enhance the nonlinearity and overcome resonant absorption. I believe this work to be the first demonstration of WVA where a deterministic interaction is used to entangle two distinct optical systems. In WVA, the amplification is contingent on discarding a large portion of the original data set. While amplification increases measurement sensitivity, discarding data worsens it. Questioning whether these competing effects conspire to improve or diminish measurement accuracy has resulted recently in controversy. I address this question by calculating the maximum amount of information achievable with the WVA technique. By comparing this information to that achievable by the standard technique, where no post-selection is employed, I show that the WVA technique can be advantageous under a certain class of noise models. Finally, I propose a way to optimally apply the WVA technique.

  12. All-optical tailoring of single-photon spectra in a quantum-dot microcavity system

    CERN Document Server

    Breddermann, Dominik; Binder, Rolf; Zrenner, Artur; Schumacher, Stefan

    2016-01-01

    Semiconductor quantum-dot cavity systems are promising sources for solid-state based on-demand generation of single photons for quantum communication. Commonly, the spectral characteristics of the emitted single photon are fixed by system properties such as electronic transition energies and spectral properties of the cavity. In the present work we study single-photon generation from the quantum-dot biexciton through a partly stimulated non-degenerate two-photon emission. We show that frequency and linewidth of the single photon can be fully controlled by the stimulating laser pulse, ultimately allowing for efficient all-optical spectral shaping of the single photon.

  13. 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.

  14. Very bright, near-infrared single photon emitters in diamond

    Directory of Open Access Journals (Sweden)

    D. W. M. Lau

    2013-09-01

    Full Text Available We demonstrate activation of bright diamond single photon emitters in the near infrared range by thermal annealing alone, i.e., without ion implantation. The activation is crucially dependent on the annealing ambient. The activation of the single photon emitters is only observed when the sample is annealed in forming gas (4% H2 in Ar above temperatures of 1000 °C. By contrast, no emitters are activated by annealing in vacuum, oxygen, argon or deuterium. The emitters activated by annealing in forming gas exhibit very bright emission in the 730-760 nm wavelength range and have linewidths of ∼1.5-2.5 nm at room temperature.

  15. Localization of Narrowband Single Photon Emitters in Nanodiamonds.

    Science.gov (United States)

    Bray, Kerem; Sandstrom, Russell; Elbadawi, Christopher; Fischer, Martin; Schreck, Matthias; Shimoni, Olga; Lobo, Charlene; Toth, Milos; Aharonovich, Igor

    2016-03-23

    Diamond nanocrystals that host room temperature narrowband single photon emitters are highly sought after for applications in nanophotonics and bioimaging. However, current understanding of the origin of these emitters is extremely limited. In this work, we demonstrate that the narrowband emitters are point defects localized at extended morphological defects in individual nanodiamonds. In particular, we show that nanocrystals with defects such as twin boundaries and secondary nucleation sites exhibit narrowband emission that is absent from pristine individual nanocrystals grown under the same conditions. Critically, we prove that the narrowband emission lines vanish when extended defects are removed deterministically using highly localized electron beam induced etching. Our results enhance the current understanding of single photon emitters in diamond and are directly relevant to fabrication of novel quantum optics devices and sensors.

  16. Single-photon superradiance and radiation trapping by atomic shells

    Science.gov (United States)

    Svidzinsky, Anatoly A.; Li, Fu; Li, Hongyuan; Zhang, Xiwen; Ooi, C. H. Raymond; Scully, Marlan O.

    2016-04-01

    The collective nature of light emission by atomic ensembles yields fascinating effects such as superradiance and radiation trapping even at the single-photon level. Light emission is influenced by virtual transitions and the collective Lamb shift which yields peculiar features in temporal evolution of the atomic system. We study how two-dimensional atomic structures collectively emit a single photon. Namely, we consider spherical, cylindrical, and spheroidal shells with two-level atoms continuously distributed on the shell surface and find exact analytical solutions for eigenstates of such systems and their collective decay rates and frequency shifts. We identify states which undergo superradiant decay and states which are trapped and investigate how size and shape of the shell affects collective light emission. Our findings could be useful for quantum information storage and the design of optical switches.

  17. Localization of narrowband single photon emitters in nanodiamonds

    CERN Document Server

    Bray, Kerem; Elbadawi, Christopher; Fischer, Martin; Schreck, Matthias; Shimoni, Olga; Lobo, Charlene; Toth, Milos; Aharonovich, Igor

    2016-01-01

    Diamond nanocrystals that host room temperature narrowband single photon emitters are highly sought after for applications in nanophotonics and bio-imaging. However, current understanding of the origin of these emitters is extremely limited. In this work we demonstrate that the narrowband emitters are point defects localized at extended morphological defects in individual nanodiamonds. In particular, we show that nanocrystals with defects such as twin boundaries and secondary nucleation sites exhibit narrowband emission that is absent from pristine individual nanocrystals grown under the same conditions. Critically, we prove that the narrowband emission lines vanish when extended defects are removed deterministically using highly localized electron beam induced etching. Our results enhance the current understanding of single photon emitters in diamond, and are directly relevant to fabrication of novel quantum optics devices and sensors.

  18. 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.

  19. Authenticated Quantum Key Distribution with Collective Detection using Single Photons

    Science.gov (United States)

    Huang, Wei; Xu, Bing-Jie; Duan, Ji-Tong; Liu, Bin; Su, Qi; He, Yuan-Hang; Jia, Heng-Yue

    2016-10-01

    We present two authenticated quantum key distribution (AQKD) protocols by utilizing the idea of collective (eavesdropping) detection. One is a two-party AQKD protocol, the other is a multiparty AQKD protocol with star network topology. In these protocols, the classical channels need not be assumed to be authenticated and the single photons are used as the quantum information carriers. To achieve mutual identity authentication and establish a random key in each of the proposed protocols, only one participant should be capable of preparing and measuring single photons, and the main quantum ability that the rest of the participants should have is just performing certain unitary operations. Security analysis shows that these protocols are free from various kinds of attacks, especially the impersonation attack and the man-in-the-middle (MITM) attack.

  20. Enhanced and directional single photon emission in hyperbolic metamaterials

    CERN Document Server

    Newman, Ward D; Jacob, Zubin

    2013-01-01

    We propose an approach to enhance and direct the spontaneous emission from isolated emitters embedded inside hyperbolic metamaterials into single photon beams. The approach rests on collective plasmonic Bloch modes of hyperbolic metamaterials which propagate in highly directional beams called quantum resonance cones. We propose a pumping scheme using the transparency window of the hyperbolic metamaterial that occurs near the topological transition. Finally, we address the challenge of outcoupling these broadband resonance cones into vacuum using a dielectric bullseye grating. We give a detailed analysis of quenching and design the metamaterial to have a huge Purcell factor in a broad bandwidth inspite of the losses in the metal. Our work should help motivate experiments in the development of single photon sources for broadband emitters such as nitrogen vacancy centers in diamond.

  1. Measurement of energetic single-photon production at LEP

    Science.gov (United States)

    Acciarri, M.; Adam, A.; Adriani, O.; Aguilar-Benitez, M.; Ahlen, S.; Alcaraz, J.; Aloisio, A.; Alverson, G.; Alviggi, M. G.; Ambrosi, G.; An, Q.; Anderhub, H.; Anderson, A. L.; Andreev, V. P.; Angelescu, T.; Antonov, L.; Antreasyan, D.; Alkhazov, G.; Arce, P.; Arefiev, A.; Azemoon, T.; Aziz, T.; Baba, P. V. K. S.; Bagnaia, P.; Bakken, J. A.; Baksay, L.; Ball, R. C.; Banerjee, S.; Banicz, K.; Barillère, R.; Barone, L.; Baschirotto, A.; Basile, M.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bencze, Gy. L.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B. L.; Biasini, M.; Biland, A.; Bilei, G. M.; Bizzarri, R.; Blaising, J. J.; Bobbink, G. J.; Bock, R.; Böhm, A.; Borgia, B.; Boucham, A.; Bourilkov, D.; Bourquin, M.; Boutigny, D.; Bouwens, B.; Brambilla, E.; Branson, J. G.; Brigljevic, V.; Brock, I. C.; Brooks, M.; Bujak, A.; Burger, J. D.; Burger, W. J.; Burgos, C.; Busenitz, J.; Buytenhuijs, A.; Bykov, A.; Cai, X. D.; Capell, M.; Cara Romeo, G.; Caria, M.; Carlino, G.; Cartacci, A. M.; Casaus, J.; Castello, R.; Cavallo, N.; Cerrada, M.; Cesaroni, F.; Chamizo, M.; Chang, Y. H.; Chaturvedi, U. K.; Chemarin, M.; Chen, A.; Chen, C.; Chen, G.; Chen, G. M.; Chen, H. F.; Chen, H. S.; Chen, M.; Chiefari, G.; Chien, C. Y.; Choi, M. T.; Chung, S.; Cifarelli, L.; Cindolo, F.; Civinini, C.; Clare, I.; Clare, R.; Coan, T. E.; Cohn, H. O.; Coignet, G.; Colino, N.; Commichau, V.; Costantini, S.; Cotorobai, F.; de la Cruz, B.; Cui, X. T.; Cui, X. Y.; Dai, T. S.; D'Alessandro, R.; de Asmundis, R.; Degré, A.; Deiters, K.; Dénes, E.; Denes, P.; DeNotaristefani, F.; DiBitonto, D.; Diemoz, M.; Dimitrov, H. R.; Dionisi, C.; Dittmar, M.; Dorne, I.; Dova, M. T.; Drago, E.; Duchesneau, D.; Duhem, F.; Duinker, P.; Duran, I.; Dutta, S.; Easo, S.; El Mamouni, H.; Engler, A.; Eppling, F. J.; Erné, F. C.; Extermann, P.; Fabbretti, R.; Fabre, M.; Falciano, S.; Favara, A.; Fay, J.; Felcini, M.; Ferguson, T.; Fernandez, D.; Fernandez, G.; Ferroni, F.; Fesefeldt, H.; Fiandrini, E.; Field, J. H.; Filthaut, F.; Fisher, P. H.; Forconi, G.; Fredj, L.; Freudenreich, K.; Gailloud, M.; Galaktionov, Yu.; Gallo, E.; Ganguli, S. N.; Garcia-Abia, P.; Gau, S. S.; Gentile, S.; Gerald, J.; Gheordanescu, N.; Giagu, S.; Goldfarb, S.; Goldstein, J.; Gong, Z. F.; Gonzalez, E.; Gougas, A.; Goujon, D.; Gratta, G.; Gruenewald, M. W.; Gu, C.; Guanziroli, M.; Gupta, V. K.; Gurtu, A.; Gustafson, H. R.; Gutay, L. J.; Hartmann, B.; Hasan, A.; Hauschildt, D.; He, J. T.; Hebbeker, T.; Hebert, M.; Hervé, A.; Hilgers, K.; Hofer, H.; Hoorani, H.; Hou, S. R.; Hu, G.; Ille, B.; Ilyas, M. M.; Innocente, V.; Janssen, H.; Jin, B. N.; Jones, L. W.; de Jong, P.; Josa-Mutuberria, I.; Kasser, A.; Khan, R. A.; Kamyshkov, Yu.; Kapinos, P.; Kapustinsky, J. S.; Karyotakis, Y.; Kaur, M.; Khokhar, S.; Kienzle-Focacci, M. N.; Kim, D.; Kim, J. K.; Kim, S. C.; Kim, Y. G.; Kinnison, W. W.; Kirkby, A.; Kirkby, D.; Kirkby, J.; Kirsch, S.; Kittel, W.; Klimentov, A.; König, A. C.; Koffeman, E.; Kornadt, O.; Koutsenko, V.; Koulbardis, A.; Kraemer, R. W.; Kramer, T.; Krastev, V. R.; Krenz, W.; Kuijten, H.; Kunin, A.; Ladron de Guevara, P.; Landi, G.; Lanzano, S.; Laurikainen, P.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Lee, D. M.; Lee, J. S.; Lee, K. Y.; Leedom, I.; Leggett, C.; Le Goff, J. M.; Leiste, R.; Lenti, M.; Leonardi, E.; Levtchenko, P.; Li, C.; Lieb, E.; Lin, W. T.; Linde, F. L.; Lindemann, B.; Lista, L.; Liu, Y.; Lohmann, W.; Longo, E.; Lu, W.; Lu, Y. S.; Lubbers, J. M.; Lübelsmeyer, K.; Luci, C.; Luckey, D.; Ludovici, L.; Luminari, L.; Lustermann, W.; Ma, W. G.; MacDermott, M.; Maity, M.; Malgeri, L.; Malik, R.; Malinin, A.; Maña, C.; Mangla, S.; Maolinbay, M.; Marchesini, P.; Marin, A.; Martin, J. P.; Marzano, F.; Massaro, G. G. G.; Mazumdar, K.; McMahon, T.; McNally, D.; Mele, S.; Merk, M.; Merola, L.; Meschini, M.; Metzger, W. J.; Mi, Y.; Mihul, A.; Mills, G. B.; Mir, Y.; Mirabelli, G.; Mnich, J.; Möller, M.; Monaco, V.; Monteleoni, B.; Morand, R.; Morganti, S.; Moulai, N. E.; Mount, R.; Müller, S.; Nagy, E.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Niaz, M. A.; Nippe, A.; Nowak, H.; Organtini, G.; Ostonen, R.; Pandoulas, D.; Paoletti, S.; Paolucci, P.; Pascale, G.; Passaleva, G.; Patricelli, S.; Paul, T.; Pauluzzi, M.; Paus, C.; Pauss, F.; Pei, Y. J.; Pensotti, S.; Perret-Gallix, D.; Pevsner, A.; Piccolo, D.; Pieri, M.; Pinto, J. C.; Piroué, P. A.; Pistolesi, E.; Plasil, F.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Postema, H.; Produit, N.; Qian, J. M.; Qureshi, K. N.; Raghavan, R.; Rahal-Callot, G.; Rancoita, P. G.; Rattaggi, M.; Raven, G.; Razis, P.; Read, K.; Redaelli, M.; Ren, D.; Ren, Z.; Rescigno, M.; Reucroft, S.; Ricker, A.; Riemann, S.; Riemers, B. C.; Riles, K.; Rind, O.; Rizvi, H. A.; Ro, S.; Robohm, A.; Rodriguez, F. J.; Roe, B. P.; Röhner, M.; Röhner, S.; Romero, L.; Rosier-Lees, S.; Rosmalen, R.; Rosselet, Ph.; van Rossum, W.; Roth, S.; Rubbia, A.; Rubio, J. A.; Rykaczewski, H.; Salicio, J.; Salicio, J. M.; Sanchez, E.; Sanders, G. S.; Santocchia, A.; Sarakinos, M. E.; Sarkar, S.; Sartorelli, G.; Sassowsky, M.; Sauvage, G.; Schäfer, C.; Schegelsky, V.; Schmitz, D.; Schmitz, P.; Schneegans, M.; Scholz, N.; Schopper, H.; Schotanus, D. J.; Shotkin, S.; Schreiber, H. J.; Shukla, J.; Schulte, R.; Schultze, K.; Schwenke, J.; Schwering, G.; Sciacca, C.; Sehgal, R.; Seiler, P. G.; Sens, J. C.; Servoli, L.; Sheer, I.; Shevchenko, S.; Shi, X. R.; Shumilov, E.; Shoutko, V.; Son, D.; Sopczak, A.; Soulimov, V.; Spartiotis, C.; Spickermann, T.; Spillantini, P.; Steuer, M.; Stickland, D. P.; Sticozzi, F.; Stone, H.; Strauch, K.; Sudhakar, K.; Sultanov, G.; Sun, L. Z.; Susinno, G. F.; Suter, H.; Swain, J. D.; Syed, A. A.; Tang, X. W.; Taylor, L.; Timellini, R.; Ting, Samuel C. C.; Ting, S. M.; Toker, O.; Tonutti, M.; Tonwar, S. C.; Tóth, J.; Trowitzsch, G.; Tsaregorodtsev, A.; Tsipolitis, G.; Tully, C.; Ulbricht, J.; Urbán, L.; Uwer, U.; Valente, E.; Van de Walle, R. T.; Vetlitsky, I.; Viertel, G.; Vikas, P.; Vikas, U.; Vivargent, M.; Vogel, H.; Vogt, H.; Vorobiev, I.; Vorobyov, A. A.; Vorobyov, An. A.; Vuilleumier, L.; Wadhwa, M.; Wallraff, W.; Wang, J. C.; Wang, X. L.; Wang, Y. F.; Wang, Z. M.; Weber, A.; Weill, R.; Willmott, C.; Wittgenstein, F.; Wright, D.; Wu, S. X.; Wynhoff, S.; Xu, Z. Z.; Yang, B. Z.; Yang, C. G.; Yang, G.; Yao, X. Y.; Ye, C. H.; Ye, J. B.; Ye, Q.; Yeh, S. C.; You, J. M.; Yunus, N.; Yzerman, M.; Zaccardelli, C.; Zemp, P.; Zeng, M.; Zeng, Y.; Zhang, D. H.; Zhang, Z. P.; Zhou, B.; Zhou, G. J.; Zhou, J. F.; Zhu, R. Y.; Zichichi, A.; van der Zwaan, B. C. C.

    1995-02-01

    We describe the sample of energetic single-photon events ( Eγ > 15 GeV) collected by L3 in the 1991-1993 LEP runs. The event distributions agree with expectations from the Standard Model. The data are used to constrain the ZZ γ coupling and to set an upper limit of 4.1 × 10 -6, μB (90% C.L.) on the the magnetic moment of the τ neutrino.

  2. 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)

  3. 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...

  4. Generation and transfer of single photons on a photonic crystal chip

    CERN Document Server

    Englund, D; Zhang, B; Yamamoto, Y; Vuckovic, J; Englund, Dirk; Faraon, Andrei; Zhang, Bingyang; Yamamoto, Yoshihisa; Vuckovic, Jelena

    2006-01-01

    We present a basic building block of a quantum network consisting of a quantum dot coupled to a source cavity, which in turn is coupled to a target cavity via a waveguide. The single photon emission from the high-Q/V source cavity is characterized by a twelve-fold spontaneous emission (SE) rate enhancement that results in a SE coupling efficiency near 0.98 into the source cavity mode. Single photons are efficiently transferred into the target cavity through the waveguide, with a source/target field intensity ratio of 0.12 (up to 0.49 observed in other structures without coupled quantum dots). This system shows great promise as a building block of future on-chip quantum information processing systems.

  5. 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-photon...

  6. 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...... emission and reproducibility of laser characteristics are important if the lasers are to be mass produced in, e. g., optofluidic sensor chips. The fabrication yield is above 85% with highly reproducible wavelengths (within 0.5%), and the temperature dependence on the wavelength is found to be -0.045 or -0...

  7. Polarization control of single photon quantum orbital angular momentum states.

    Science.gov (United States)

    Nagali, E; Sciarrino, F; De Martini, F; Piccirillo, B; Karimi, E; Marrucci, L; Santamato, E

    2009-10-12

    The orbital angular momentum of photons, being defined in an infinite-dimensional discrete Hilbert space, offers a promising resource for high-dimensional quantum information protocols in quantum optics. The biggest obstacle to its wider use is presently represented by the limited set of tools available for its control and manipulation. Here, we introduce and test experimentally a series of simple optical schemes for the coherent transfer of quantum information from the polarization to the orbital angular momentum of single photons and vice versa. All our schemes exploit a newly developed optical device, the so-called "q-plate", which enables the manipulation of the photon orbital angular momentum driven by the polarization degree of freedom. By stacking several q-plates in a suitable sequence, one can also have access to higher-order angular momentum subspaces. In particular, we demonstrate the control of the orbital angular momentum m degree of freedom within the subspaces of |m| = 2h and |m| = 4h per photon.

  8. Fano fluctuations in superconducting-nanowire single-photon detectors

    Science.gov (United States)

    Kozorezov, A. G.; Lambert, C.; Marsili, F.; Stevens, M. J.; Verma, V. B.; Allmaras, J. P.; Shaw, M. D.; Mirin, R. P.; Nam, Sae Woo

    2017-08-01

    Because of their universal nature, Fano fluctuations are expected to influence the response of superconducting-nanowire single-photon detectors (SNSPDs). We predict that photon counting rate (P C R ) as a function of bias current (IB) in SNSPDs is described by an integral over a transverse coordinate-dependent complementary error function. Fano fluctuations in the amount of energy deposited into the electronic system contribute to the finite width of this error function Δ IB . The local response of an SNSPD can also affect this width: the location of the initial photon absorption site across the width of the wire can impact the probability of vortex-antivortex unbinding and vortex entry from the edges. In narrow-nanowire SNSPDs, the local responses are uniform, and Fano fluctuations dominate Δ IB . We demonstrate good agreement between theory and experiments for a series of bath temperatures and photon energies in narrow-wire WSi SNSPDs. In a wide-nanowire device, the strong local dependence will introduce a finite width to the P C R curve, but with sharp cusps. We show how Fano fluctuations can smooth these features to produce theoretical curves that better match experimental data. We also show that the time-resolved hotspot relaxation curves predicted by Fano fluctuations match the previously measured Lorentzian shapes (except for their tails) over the entire range of bias currents investigated experimentally.

  9. Experimental observation of anomalous trajectories of single photons

    Science.gov (United States)

    Zhou, Zong-Quan; Liu, Xiao; Kedem, Yaron; Cui, Jin-Min; Li, Zong-Feng; Hua, Yi-Lin; Li, Chuan-Feng; Guo, Guang-Can

    2017-04-01

    A century after its conception, quantum mechanics still hold surprises that contradict many "common sense" notions. The contradiction is especially sharp in case one consider trajectories of truly quantum objects such as single photons. From a classical point of view, trajectories are well defined for particles, but not for waves. The wave-particle duality forces a breakdown of this dichotomy and quantum mechanics resolves this in a remarkable way: Trajectories can be well defined, but they are utterly different from classical trajectories. Here, we give an operational definition to the trajectory of a single photon by introducing a technique to mark its path using its spectral composition. The method demonstrates that the frequency degree of freedom can be used as a bona fide quantum measurement device (meter). The analysis of a number of setups, using our operational definition, leads to anomalous trajectories which are noncontinuous and in some cases do not even connect the source of the photon to where it is detected. We carried out an experimental demonstration of these anomalous trajectories using a nested interferometer. We show that the two-state vector formalism provides a simple explanation for the results.

  10. 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.

  11. Theory of single photon on demand from a single molecule source.

    Science.gov (United States)

    He, Yong; Barkai, Eli

    2006-11-21

    We consider the theory of single photon on demand from a two level atom or molecule source. Using optical Bloch equations and the generating function formalism we investigate three approaches to single photon control: (i) the square laser pulse; (ii) the square modulation of absorption frequency; and (iii) the rapid adiabatic following approach investigated in the experiments of Brunel et al., Phys. Rev. Lett., 1999, 83, 2722. We discuss the conditions for obtaining the maximum of the probability of emission of a single photon and a pair of photons, under the constrains of finite field strength and finite interaction time with excitation field. We obtain analytical expression for the probability of emitting zero, one, and two photons for the square pulse, and discuss semi-classical and strongly quantum limiting cases. Numerical results obtained from the generating function formalism are compared with experimental results showing that the two level system approach is suitable for the description of cryogenic temperature single molecules, and that experiments were conducted very close to the optimal conditions.

  12. A single probe for imaging photons, electrons and physical forces

    Science.gov (United States)

    Pilet, Nicolas; Lisunova, Yuliya; Lamattina, Fabio; Stevenson, Stephanie E.; Pigozzi, Giancarlo; Paruch, Patrycja; Fink, Rainer H.; Hug, Hans J.; Quitmann, Christoph; Raabe, Joerg

    2016-06-01

    The combination of complementary measurement techniques has become a frequent approach to improve scientific knowledge. Pairing of the high lateral resolution scanning force microscopy (SFM) with the spectroscopic information accessible through scanning transmission soft x-ray microscopy (STXM) permits assessing physical and chemical material properties with high spatial resolution. We present progress from the NanoXAS instrument towards using an SFM probe as an x-ray detector for STXM measurements. Just by the variation of one parameter, the SFM probe can be utilised to detect either sample photo-emitted electrons or transmitted photons. This allows the use of a single probe to detect electrons, photons and physical forces of interest. We also show recent progress and demonstrate the current limitations of using a high aspect ratio coaxial SFM probe to detect photo-emitted electrons with very high lateral resolution. Novel probe designs are proposed to further progress in using an SFM probe as a STXM detector.

  13. 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.

  14. Modal coupling of single photons to a nanofibre

    CERN Document Server

    Gaio, Michele; Castro-Lopez, Marta; Pisignano, Dario; Camposeo, Andrea; Sapienza, Riccardo

    2015-01-01

    Nanoscale quantum optics of individual light emitters placed in confined geometries is developing as an exciting new research field aiming at efficient manipulation of single-photons . This requires selective channelling of light into specific optical modes of nanophotonic structures. Hybrid photonic systems combining emitters with nanostructured media can yield this functionality albeit limited by the required nanometre-scale spatial and spectral coupling. Furthermore, assessing the coupling strength presents significant challenges and disentangling the different modal contribution is often impossible. Here, we show that momentum spectroscopy of individually addressed emitters, embedded in a nanofibre, can be used to quantify the modal coupling efficiency to the nanofibre modes. For free-standing polymer nanofibres doped with colloidal quantum dots, we report broadband coupling to the fundamental mode of up $\\beta_{01}=31\\pm2\\%$, in robust agreement with theoretical calculations. Electrospun soft-matter nano...

  15. Single-photon multi-ports router based on the coupled cavity optomechanical system.

    Science.gov (United States)

    Li, Xun; Zhang, Wen-Zhao; Xiong, Biao; Zhou, Ling

    2016-12-22

    A scheme of single-photon multi-port router is put forward by coupling two optomechanical cavities with waveguides. It is shown that the coupled two optomechanical cavities can exhibit photon blockade effect, which is generated from interference of three mode interaction. A single-photon travel along the system is calculated. The results show that the single photon can be controlled in the multi-port system because of the radiation pressure, which should be useful for constructing quantum network.

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

    OpenAIRE

    Hirvonen, Liisa Maija; Barber, Matthew; Suhling, Klaus

    2016-01-01

    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, w...

  17. Characterization of a Spontaneous Parametric Downconversion Source for Use in Single Photon Tests of Quantum Mechanics

    Science.gov (United States)

    Alexander, Preston; McDonld, Jackson; Harrington, Jason; Smith, R. Seth

    2014-03-01

    During the past year, a quantum optics laboratory was constructed and tested at Francis Marion University. A spontaneous parametric downconversion source was used to create pairs of correlated photons for use in single photon tests of quantum mechanics. Photons from a spontaneous parametric downconversion source were detected with single photon counting modules that were purchased through the Advanced Laboratory Physics Association (ALPHA). The effect of pump polarization on the output intensity was studied. Coincidences between pairs of correlated photons were counted and plotted as a function of the angle between the single photon detectors, in order to perform a test of Conservation of Momentum. The laboratory will be used to perform single photon tests of quantum mechanics, including the Grangier experiment, single photon interference, quantum state measurement, and tests of local realism.

  18. Single-Photon Switching and Entanglement of Solid-State Qubits in an Integrated Nanophotonic System

    CERN Document Server

    Sipahigil, Alp; Sukachev, Denis D; Burek, Michael J; Borregaard, Johannes; Bhaskar, Mihir K; Nguyen, Christian T; Pacheco, Jose L; Atikian, Haig A; Meuwly, Charles; Camacho, Ryan M; Jelezko, Fedor; Bielejec, Edward; Park, Hongkun; Lončar, Marko; Lukin, Mikhail D

    2016-01-01

    Efficient interfaces between photons and quantum emitters form the basis for quantum networks and enable nonlinear optical devices operating at the single-photon level. We demonstrate an integrated platform for scalable quantum nanophotonics based on silicon-vacancy (SiV) color centers coupled to nanoscale diamond devices. By placing SiV centers inside diamond photonic crystal cavities, we realize a quantum-optical switch controlled by a single color center. We control the switch using SiV metastable orbital states and verify optical switching at the single-photon level by using photon correlation measurements. We use Raman transitions to realize a single-photon source with a tunable frequency and bandwidth in a diamond waveguide. Finally, we create entanglement between two SiV centers by detecting indistinguishable Raman photons emitted into a single waveguide. Entanglement is verified using a novel superradiant feature observed in photon correlation measurements, paving the way for the realization of quantu...

  19. Detection of single photons by toad and mouse rods.

    Science.gov (United States)

    Reingruber, Jürgen; Pahlberg, Johan; Woodruff, Michael L; Sampath, Alapakkam P; Fain, Gordon L; Holcman, David

    2013-11-26

    Amphibian and mammalian rods can both detect single photons of light even though they differ greatly in physical dimensions, mammalian rods being much smaller in diameter than amphibian rods. To understand the changes in physiology and biochemistry required by such large differences in outer segment geometry, we developed a computational approach, taking into account the spatial organization of the outer segment divided into compartments, together with molecular dynamics simulations of the signaling cascade. We generated simulations of the single-photon response together with intrinsic background fluctuations in toad and mouse rods. Combining this computational approach with electrophysiological data from mouse rods, we determined key biochemical parameters. On average around one phosphodiesterase (PDE) molecule is spontaneously active per mouse compartment, similar to the value for toad, which is unexpected due to the much smaller diameter in mouse. A larger number of spontaneously active PDEs decreases dark noise, thereby improving detection of single photons; it also increases cGMP turnover, which accelerates the decay of the light response. These constraints explain the higher PDE density in mammalian compared with amphibian rods that compensates for the much smaller diameter of mammalian disks. We further find that the rate of cGMP hydrolysis by light-activated PDE is diffusion limited, which is not the case for spontaneously activated PDE. As a consequence, in the small outer segment of a mouse rod only a few activated PDEs are sufficient to generate a signal that overcomes noise, which permits a shorter lifetime of activated rhodopsin and greater temporal resolution.

  20. Performance limits of a single photon counting pixel system

    Science.gov (United States)

    Chmeissani, M.; Mikulec, B.

    2001-03-01

    X-ray imaging using hybrid pixel detectors in single photon counting mode is a relatively recent and exciting development. The photon counting mode implies that each pixel has a threshold in energy above which a hit is recorded. Sharing of charge between adjacent pixels would therefore lead to a loss of registered hits and for medical imaging applications to a higher patient dose. This explains why the demand for high spatial resolution and consequently small pixel sizes (<100 μm) motivates the Medipix2 collaboration to study the effects of charge sharing between pixels on system performance. Two different simulation codes are used to simulate the energy loss inside the detector and the charge transport towards the pixel electrodes. The largest contribution to the lateral spreading of charge comes from diffusion and can result in a considerable loss of detection efficiency in photon counting systems for small pixel sizes. The Medipix2 collaboration consists of groups from Barcelona, Cagliari, CEA/Leti DEIN, CERN, Freiburg, Glasgow, Mitthögskolan, Napoli, NIKHEF, MRC lab Cambridge, Pisa, Prague and Sassari.

  1. Characterization of parallel superconducting nanowire single photon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Ejrnaes, M; Casaburi, A; Pagano, S; Cristiano, R [CNR-Istituto di Cibernetica ' E Caianiello' , 80078 Pozzuoli (Namibia) (Italy); Quaranta, O; Marchetti, S [Dipartimento di Fisica ' E R Caianiello' , Universita di Salerno, 84081 Baronissi (Italy); Gaggero, A; Mattioli, F; Leoni, R [CNR-Istituto di Fotonica e Nanotecnologie, 00156 Roma (Italy)

    2009-05-15

    Superconducting nanowire single photon detectors (SNSPDs) have been realized using an innovative parallel wire configuration. This configuration allows, at the same time, a large detection area and a fast response, with the additional advantage of large signal amplitudes. The detectors have been thoroughly characterized in terms of signal properties (amplitude, risetime and falltime), detector operation (latching and not latching) and quantum efficiency (at 850 nm). It has been shown that the parallel SNSPD is able to provide significantly higher maximum count rates for large area SNSPDs than meandered SNSPDs. Through a proper parallel wire configuration the increase in maximum count rate can be obtained without latching problems.

  2. 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.

  3. High bit rate germanium single photon detectors for 1310nm

    Science.gov (United States)

    Seamons, J. A.; Carroll, M. S.

    2008-04-01

    There is increasing interest in development of high speed, low noise and readily fieldable near infrared (NIR) single photon detectors. InGaAs/InP Avalanche photodiodes (APD) operated in Geiger mode (GM) are a leading choice for NIR due to their preeminence in optical networking. After-pulsing is, however, a primary challenge to operating InGaAs/InP single photon detectors at high frequencies1. After-pulsing is the effect of charge being released from traps that trigger false ("dark") counts. To overcome this problem, hold-off times between detection windows are used to allow the traps to discharge to suppress after-pulsing. The hold-off time represents, however, an upper limit on detection frequency that shows degradation beginning at frequencies of ~100 kHz in InGaAs/InP. Alternatively, germanium (Ge) single photon avalanche photodiodes (SPAD) have been reported to have more than an order of magnitude smaller charge trap densities than InGaAs/InP SPADs2, which allowed them to be successfully operated with passive quenching2 (i.e., no gated hold off times necessary), which is not possible with InGaAs/InP SPADs, indicating a much weaker dark count dependence on hold-off time consistent with fewer charge traps. Despite these encouraging results suggesting a possible higher operating frequency limit for Ge SPADs, little has been reported on Ge SPAD performance at high frequencies presumably because previous work with Ge SPADs has been discouraged by a strong demand to work at 1550 nm. NIR SPADs require cooling, which in the case of Ge SPADs dramatically reduces the quantum efficiency of the Ge at 1550 nm. Recently, however, advantages to working at 1310 nm have been suggested which combined with a need to increase quantum bit rates for quantum key distribution (QKD) motivates examination of Ge detectors performance at very high detection rates where InGaAs/InP does not perform as well. Presented in this paper are measurements of a commercially available Ge APD

  4. Secure authentication of classical messages with single photons

    Institute of Scientific and Technical Information of China (English)

    Wang Tian-Yin; Wen Qiao-Yan; Zhu Fu-Chen

    2009-01-01

    This paper proposes a scheme for secure authentication of classical messages with single photons and a hashed function.The security analysis of this scheme is also given,which shows that anyone cannot forge valid message authentication codes (MACs).In addition,the lengths of the authentication key and the MACs are invariable and shorter,in comparison with those presented authentication schemes.Moreover,quantum data storage and entanglement are not required in this scheme.Therefore,this scheme is more efficient and economical.

  5. 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.

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

    CERN Document Server

    Tanner, Michael G; Hadfield, Robert H

    2013-01-01

    We explore optimised control of superconducting nanowire single-photon detectors (SNSPDs) through bright illumination. We consider the behaviour of the SNSPD in the shunted configuration (a practical measure to avoid latching) in long-running quantum key distribution experiments. We propose and demonstrate an effective bright-light attack on this realistic configuration, by applying transient blinding illumination lasting for a fraction of a microsecond and producing several deterministic fake clicks during this time. We show that this attack does not lead to elevated timing jitter in the spoofed output pulse, and is hence not introducing significant errors. Five different SNSPD chip designs were tested. We consider possible countermeasures to this attack.

  7. 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.

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

    Science.gov (United States)

    Liu, Hongwei; Ma, Haiqiang; Wei, Kejin; Yang, Xiuqing; Qu, Wenxiu; Dou, Tianqi; Chen, Yitian; Li, Ruixue; Zhu, Wu

    2016-07-01

    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.

  9. Single Photon Detector at Telecom Wavelengths for Quantum Key Distribution

    Institute of Scientific and Technical Information of China (English)

    LIU Yun; WU Qing-Lin; HAN Zheng-Fu; DAI Yi-Min; QUO Guang-Can

    2006-01-01

    Using InGaAs/InP avalanche photodiodes as sensors and coaxial cables as reflection lines to reject spike signals, we have firstly employed the "timing filtering" gates to pick out avalanche signals and have realized the single photon detection at 1550 nm in the temperature range of thermoelectric cooling. A ratio of the dark count rate to the detection efficiency was obtained to be 9×10-5 at 223K. When the detector is applied to a practical quantum key distribution system, the transmission distance can reach 89.5km and the repetition rate can reach 0.33MHz.

  10. 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 potent....... A first implementation of this strategy has lead to an ultra-bright single-photon source with a first-lens external efficiency of 0.75 ± 0.1 and a predicted coupling to a Gaussian beam of 0.61 ± 0.08.......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...... potential. However, the device requires a delicate, sharp needle-like taper with performance sensitive to minute geometrical details. To overcome this limitation we demonstrate the photonic trumpet, exploiting an opposite tapering strategy. The trumpet features a strongly Gaussian far-field emission...

  11. cGMP in Mouse Rods: the spatiotemporal dynamics underlying single photon responses

    Directory of Open Access Journals (Sweden)

    Owen P. Gross

    2015-03-01

    Full Text Available Vertebrate vision begins when retinal photoreceptors transduce photons into membrane hyperpolarization, which reduces glutamate release onto second-order neurons. In rod photoreceptors, transduction of single photons is achieved by a well-understood G-protein cascade that modulates cGMP levels, and in turn, cGMP-sensitive inward current. The spatial extent and depth of the decline in cGMP during the single photon response have been major issues in phototransduction research since the discovery that single photons elicit substantial and reproducible changes in membrane current. The spatial profile of cGMP decline during the single photon response affects signal gain, and thus may contribute to reduction of trial-to-trial fluctuations in the single photon response. Here we summarize the general principles of rod phototransduction, emphasizing recent advances in resolving the spatiotemporal dynamics of cGMP during the single photon response.

  12. Observation of non-diffracting behavior at the single-photon level

    CERN Document Server

    Cruz-Ramirez, Hector; Morelos, Francisco J; Quinto-Su, Pedro A; Gutierrez-Vega, Julio C; U'Ren, Alfred B

    2013-01-01

    We demonstrate the generation of non-diffracting heralded single photons, i.e. which are characterized by a single-photon transverse intensity distribution which remains essentially unchanged over a significant propagation distance. For this purpose we have relied on the process of spontaneous parametric downconversion (SPDC) for the generation of signal and idler photon pairs, where our SPDC crystal is pumped by a Bessel-Gauss (BG) beam. Our experiment shows that the well-understood non-diffracting behavior of a BG beam may be directly mapped to the signal-mode, single photons heralded by the detection of a single idler photon. In our experiment, the heralded single photon is thus arranged to be non-diffracting without the need for projecting its single-photon transverse amplitude, post-generation, in any manner.

  13. 64-pixel NbTiN superconducting nanowire single-photon detector array for spatially resolved photon detection

    CERN Document Server

    Miki, Shigehito; Wang, Zhen; Terai, Hirotaka

    2014-01-01

    We present the characterization of two-dimensionally arranged 64-pixel NbTiN superconducting nanowire single-photon detector array for spatially resolved photon detection. NbTiN films deposited on thermally oxidized Si substrates enabled the high-yield production of high-quality SSPD pixels, and all 64 SSPD pixels showed uniform superconducting characteristics. Furthermore, all of the pixels showed single-photon sensitivity, and 60 of the 64 pixels showed a pulse generation probability higher than 90% after photon absorption. As a result of light irradiation from the single-mode optical fiber at different distances between the fiber tip and the active area, the variations of system detection efficiency in each pixel showed reasonable Gaussian distribution to represent the spatial distributions of photon flux intensity.

  14. A bright on-demand source of indistinguishable single photons at telecom wavelengths

    CERN Document Server

    Kim, Je-Hyung; Richardson, Christopher J K; Leavitt, Richard P; Waks, Edo

    2015-01-01

    Long-distance quantum communication relies on the ability to efficiently generate and prepare single photons at telecom wavelengths. In many applications these photons must also be indistinguishable such that they exhibit interference on a beamsplitter, which implements effective photon-photon interactions. However, deterministic generation of indistinguishable single photons with high brightness remains a challenging problem. We demonstrate a telecom wavelength source of indistinguishable single photons using an InAs/InP quantum dot in a nanophotonic cavity. The cavity enhances the quantum dot emission, resulting in a nearly Gaussian transverse mode profile with high out-coupling efficiency exceeding 46%, leading to detected photon count rates that would exceed 1.5 million counts per second. We also observe Purcell enhanced spontaneous emission rate as large as 4. Using this source, we generate linearly polarized, high purity single photons at telecom-wavelength and demonstrate the indistinguishable nature o...

  15. Calibration of a single-photon counting detectors without the need of input photon flux calibration (Conference Presentation)

    Science.gov (United States)

    Gerrits, Thomas

    2017-05-01

    Calibration of fiber-coupled single-photon detectors usually requires knowledge of the input photon flux inside the fiber and/or knowledge of the linearity of a reference power meter. Many approaches have been presented in the past to accurately measure the photon detection probability of a single photon detector [1-6]. Under certain assumptions, one can utilize waveguide-coupled single photon detectors and a series of photon-counting measurements and a single-photon source to calibrate the detection efficiency of a single photon detector without the need of a reference power meter and the knowledge of the incoming photon flux. Here, this method is presented. Furthermore, if a reference detector is used, the detection efficiency of all evanescently coupled waveguide detectors can be measured, and the measurement outcome does not depend on splicing or fiber connection losses within in the setup, i.e., the measurement is setup-independent. In addition, the method, when using a reference detector, can be utilized to measure and distinguish between the absorption of a waveguide-coupled single photon detector and its internal detection efficiency. [1] A. J. Miller et al, Opt. Express 19, 9102-9110 (2011) [2] I. Muller et al., Metrologia 51, S329 (2014). [3] A. L. Migdall, Instrumentation and Measurement, IEEE Transactions on 50, 478-481 (2001). [4] S. V. Polyakov, A. L. Migdall, Optics Express 15, 1390-1407 (2007). [5] A. Avella et al., Optics Express 19, 23249-23257 (2011). [6] T. Lunghi et al., Opt. Express 22, 18078-18092 (2014)

  16. Design of Slow and Fast Light Photonic Crystal Waveguides for Single-photon Emission Using a Bloch Mode Expansion Technique

    DEFF Research Database (Denmark)

    de Lasson, Jakob Rosenkrantz; Rigal, B.; Kapon, E.;

    We design slow and fast light photonic crystal waveguides for single-photon emission using a Bloch mode expansion and scattering matrix technique. We propose slow light designs that increase the group index-waveguide mode volume ratio for larger Purcell enhancement, and address efficient slow...

  17. 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....

  18. 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...... the light emission profile and the possibilities of tailoring it as well as the mechanisms governing the coherence are elucidated. The major design strategies pursued to optimize the single-photon source performance and the remaining challenges are reviewed....

  19. 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.)

  20. Single nanoparticle detection using photonic crystal enhanced microscopy.

    Science.gov (United States)

    Zhuo, Yue; Hu, Huan; Chen, Weili; Lu, Meng; Tian, Limei; Yu, Hojeong; Long, Kenneth D; Chow, Edmond; King, William P; Singamaneni, Srikanth; Cunningham, Brian T

    2014-03-07

    We demonstrate a label-free biosensor imaging approach that utilizes a photonic crystal (PC) surface to detect surface attachment of individual dielectric and metal nanoparticles through measurement of localized shifts in the resonant wavelength and resonant reflection magnitude from the PC. Using a microscopy-based approach to scan the PC resonant reflection properties with 0.6 μm spatial resolution, we show that metal nanoparticles attached to the biosensor surface with strong absorption at the resonant wavelength induce a highly localized reduction in reflection efficiency and are able to be detected by modulation of the resonant wavelength. Experimental demonstrations of single-nanoparticle imaging are supported by finite-difference time-domain computer simulations. The ability to image surface-adsorption of individual nanoparticles offers a route to single molecule biosensing, in which the particles can be functionalized with specific recognition molecules and utilized as tags.

  1. Single-Photon Superradiance from a Quantum Dot

    Science.gov (United States)

    Tighineanu, Petru; Daveau, Raphaël S.; Lehmann, Tau B.; Beere, Harvey E.; Ritchie, David A.; Lodahl, Peter; Stobbe, Søren

    2016-04-01

    We report on the observation of single-photon superradiance from an exciton in a semiconductor quantum dot. The confinement by the quantum dot is strong enough for it to mimic a two-level atom, yet sufficiently weak to ensure superradiance. The electrostatic interaction between the electron 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.

  2. Bright single photon emission from a quantum dot in a circular Bragg grating microcavity

    CERN Document Server

    Ates, Serkan; Davanco, Marcelo; Badolato, Antonio; Srinivasan, Kartik

    2011-01-01

    Bright single photon emission from single quantum dots in suspended circular Bragg grating microcavities is demonstrated. This geometry has been designed to achieve efficient (> 50 %) single photon extraction into a near-Gaussian shaped far-field pattern, modest (~10x) Purcell enhancement of the radiative rate, and a spectral bandwidth of a few nanometers. Measurements of fabricated devices show progress towards these goals, with collection efficiencies as high as ~10% demonstrated with moderate spectral bandwidth and rate enhancement. Photon correlation measurements are performed under above-bandgap excitation (pump wavelength = 780 nm to 820 nm) and confirm the single photon character of the collected emission. While the measured sources are all antibunched and dominantly composed of single photons, the multi-photon probability varies significantly. Devices exhibiting tradeoffs between collection efficiency, Purcell enhancement, and multi-photon probability are explored and the results are interpreted with ...

  3. 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.

  4. 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

    2015-11-01

    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.

  5. Collaborative single target detection for depth imaging from sparse single-photon data

    CERN Document Server

    Altmann, Yoann; McCarthy, Aongus; Buller, Gerald S; McLaughlin, Steve

    2016-01-01

    This paper presents a new Bayesian model and associated algorithm for depth and intensity profiling using full waveforms from time-correlated single-photon counting (TCSPC) measurements in the limit of very low photon counts (i.e., typically less than $20$ photons per pixel). The model represents each Lidar waveform as an unknown constant background level, which is combined in the presence of a target, to a known impulse response weighted by the target intensity and finally corrupted by Poisson noise. The joint target detection and depth imaging problem is expressed as a pixel-wise model selection and estimation problem which is solved using Bayesian inference. Prior knowledge about the problem is embedded in a hierarchical model that describes the dependence structure between the model parameters while accounting for their constraints. In particular, Markov random fields (MRFs) are used to model the joint distribution of the background levels and of the target presence labels, which are both expected to exhi...

  6. Action of angiotensin II, 5-hydroxytryptamine and adenosine triphosphate on ionic currents in single ear artery cells of the rabbit.

    Science.gov (United States)

    Hughes, A D; Bolton, T B

    1995-10-01

    1. Angiotensin II, 5-hydroxytryptamine (5-HT) and adenosine triphosphate (ATP) evoked a transient inward current in isolated single car artery cells of rabbit held at -60 mV by whole cell voltage clamp in physiological saline using a KCL-containing pipette solution. Under these conditions agonist did not activate a calcium-dependent potassium current. 2. Responses to each agonist were transient and desensitized rapidly. Inward current at -60 mV holding potential was not abolished by blockade of voltage-dependent calcium channels or by buffering intracellular calcium with BAPTA, a calcium chelator, or following depletion of intracellular calcium stores with ryanodine. 3. The shape of the current-voltage relationships and the reversal potentials of the current induced by angiotensin II, 5-HT and ATP were similar under a variety of ionic conditions. Agonist-induced current was unaffected by replacing intracellular chloride with citrate ions or by replacing intracellular sodium with caesium or extracellular sodium with barium or calcium. Replacement of extracellular sodium with Tris shifted the reversal potential in all cases by around 30 mV negatively. 4. These data suggest that angiotensin II, 5-HT and ATP activate similar cationic conductances which are relatively non-selective allowing mono- and divalent cations to cross the smooth muscle cell membrane. These channels may allow the influx of calcium under physiological conditions.

  7. On-chip low loss heralded source of pure single photons

    CERN Document Server

    Spring, Justin B; Metcalf, Benjamin J; Humphreys, Peter C; Moore, Merritt; Thomas-Peter, Nicholas; Barbieri, Marco; Jin, Xian-Min; Langford, Nathan K; Kolthammer, W Steven; Booth, Martin J; Walmsley, Ian A

    2013-01-01

    A key obstacle to the experimental realization of many photonic quantum-enhanced technologies is the lack of low-loss sources of single photons in pure quantum states. We demonstrate a promising solution: generation of heralded single photons in a silica photonic chip by spontaneous four-wave mixing. A heralding efficiency of 40%, corresponding to a preparation efficiency of 80% accounting for detector performance, is achieved due to efficient coupling of the low-loss source to optical fibers. A single photon purity of 0.86 is measured from the source number statistics without filtering, and confirmed by direct measurement of the joint spectral intensity. We calculate that similar high-heralded-purity output can be obtained from visible to telecom spectral regions using this approach. On-chip silica sources can have immediate application in a wide range of single-photon quantum optics applications which employ silica photonics.

  8. All-fibre multiplexed source of high-purity heralded single photons

    CERN Document Server

    Francis-Jones, Robert J A; Mosley, Peter J

    2016-01-01

    Single photon sources based on spontaneous photon-pair generation have enabled pioneering experiments in quantum optics. However, their non-determinism presents a bottleneck to scaling up photonic and hybrid quantum-enhanced technologies. Furthermore, photon pairs are typically emitted into many correlated frequency modes, producing an undesirable mixed state on heralding. Here we present a complete fibre-integrated heralded single photon source that addresses both these difficulties simultaneously. We use active switching to provide a path to deterministic operation by multiplexing separate spontaneous sources, and dispersion engineering to minimise frequency correlation for high-purity single photon generation. All the essential elements -- nonlinear material with dispersion control, wavelength isolation, optical delay, and fast switching -- are incorporated in a low-loss alignment-free package that heralds photons in telecoms single-mode fibre. Our results demonstrate a scalable approach to delivering pure...

  9. An on-chip coupled resonator optical waveguide single-photon buffer.

    Science.gov (United States)

    Takesue, Hiroki; Matsuda, Nobuyuki; Kuramochi, Eiichi; Munro, William J; Notomi, Masaya

    2013-01-01

    Integrated quantum optical circuits are now seen as one of the most promising approaches with which to realize single-photon quantum information processing. Many of the core elements for such circuits have been realized, including sources, gates and detectors. However, a significant missing function necessary for photonic quantum information processing on-chip is a buffer, where single photons are stored for a short period of time to facilitate circuit synchronization. Here we report an on-chip single-photon buffer based on coupled resonator optical waveguides (CROW) consisting of 400 high-Q photonic crystal line-defect nanocavities. By using the CROW, a pulsed single photon is successfully buffered for 150 ps with 50-ps tunability while maintaining its non-classical properties. Furthermore, we show that our buffer preserves entanglement by storing and retrieving one photon from a time-bin entangled state. This is a significant step towards an all-optical integrated quantum information processor.

  10. An on-chip coupled resonator optical waveguide single-photon buffer

    CERN Document Server

    Takesue, Hiroki; Kuramochi, Eiichi; Munro, Willian J; Notomi, Masaya

    2013-01-01

    Integrated quantum optical circuits are now seen as one of the most promising approaches with which to realize single photon quantum information processing. Many of the core elements for such circuits have been realized including sources, gates and detectors. However, a significant missing function necessary for photonic information processing on-chip is a buffer, where single photons are stored for a short period of time to facilitate circuit synchronization. Here we report an on-chip single photon buffer based on coupled resonator optical waveguides (CROW) consisting of 400 high-Q photonic crystal line defect nanocavities. By using the CROW, a pulsed single photon was successfully buffered for 150 ps with 50-ps tunability while maintaining its non-classical properties. Furthermore, we showed that our buffer preserves entanglement by storing and retrieving one photon from a time-bin entangled state. This is a significant step towards an all-optical integrated quantum information processor.

  11. 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.

  12. Triangular nanobeam photonic cavities in single crystal diamond

    CERN Document Server

    Bayn, Igal; Salzman, Joseph; Kalish, Rafi

    2011-01-01

    Diamond photonics provides an attractive architecture to explore room temperature cavity quantum electrodynamics and to realize scalable multi-qubit computing. Here we review the present state of diamond photonic technology. The design, fabrication and characterization of a novel triangular cross section nanobeam cavity produced in a single crystal diamond is demonstrated. The present cavity design, based on a triangular cross section allows vertical confinement and better signal collection efficiency than that of slab-based nanocavities, and eliminates the need for a pre-existing membrane. The nanobeam is fabricated by Focused-Ion-Beam (FIB) patterning. The cavity is characterized by a confocal photoluminescence. The modes display quality factors of Q ~220 and are deviated in wavelength by only ~1.7nm from the NV- color center zero phonon line (ZPL). The measured results are found in good agreement with 3D Finite-Difference-Time-Domain (FDTD) calculations. A more advanced cavity design with Q=22,000 is model...

  13. Optical gain in single tensile-strained germanium photonic wire.

    Science.gov (United States)

    de Kersauson, M; El Kurdi, M; David, S; Checoury, X; Fishman, G; Sauvage, S; Jakomin, R; Beaudoin, G; Sagnes, I; Boucaud, P

    2011-09-12

    We have investigated the optical properties of tensile-strained germanium photonic wires. The photonic wires patterned by electron beam lithography (50 μm long, 1 μm wide and 500 nm thick) are obtained by growing a n-doped germanium film on a GaAs substrate. Tensile strain is transferred in the germanium layer using a Si₃N₄ stressor. Tensile strain around 0.4% achieved by the technique corresponds to an optical recombination of tensile-strained germanium involving light hole band around 1690 nm at room temperature. We show that the waveguided emission associated with a single tensile-strained germanium wire increases superlinearly as a function of the illuminated length. A 20% decrease of the spectral broadening is observed as the pump intensity is increased. All these features are signatures of optical gain. A 80 cm⁻¹ modal optical gain is derived from the variable strip length method. This value is accounted for by the calculated gain material value using a 30 band k · p formalism. These germanium wires represent potential building blocks for integration of nanoscale optical sources on silicon.

  14. 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...

  15. Single photon emission and detection at the nanoscale utilizing semiconductor nanowires

    NARCIS (Netherlands)

    Reimer, M.E.; van Kouwen, M.P.; Barkelid, M., et al.

    2011-01-01

    We report recent progress toward on-chip single photon emission and detection in the near infrared utilizing semiconductor nanowires. Our single photon emitter is based on a single InAsP quantum dot embedded in a p-n junction defined along the growth axis of an InP nanowire. Under forward bias,

  16. Conditional generation of arbitrary single-mode quantum states of light by repeated photon subtractions

    CERN Document Server

    Fiurasek, J; Cerf, N J; Fiurasek, Jaromir; Garcia-Patron, Raul; Cerf, Nicolas J.

    2005-01-01

    We propose a scheme for the conditional generation of arbitrary finite superpositions of (squeezed) Fock states in a single mode of a traveling optical field. The suggested setup requires only a source of squeezed states, beam splitters, strong coherent beams, and photodetectors with single-photon sensitivity. The method does not require photodetectors with a high efficiency nor with a single-photon resolution.

  17. Single photon emission and detection at the nanoscale utilizing semiconductor nanowires

    NARCIS (Netherlands)

    Reimer, M.E.; van Kouwen, M.P.; Barkelid, M., et al.

    2011-01-01

    We report recent progress toward on-chip single photon emission and detection in the near infrared utilizing semiconductor nanowires. Our single photon emitter is based on a single InAsP quantum dot embedded in a p-n junction defined along the growth axis of an InP nanowire. Under forward bias, ligh

  18. Single photon emission computed tomography (SPECT) in epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Leroy, R.F. [Univ. of Texas Southwestern Medical School, Dallas (United States)

    1991-12-31

    Epilepsy is a common neurologic disorder which has just begun to be studied with single photon emission computerized tomography (SPECT). Epilepsy usually is studied with electroencephalographic (EEG) techniques that demonstrate the physiologic changes that occur during seizures, and with neuroimaging techniques that show the brain structures where seizures originate. Neither method alone has been adequate to describe the pathophysiology of the patient with epilepsy. EEG techniques lack anatomic sensitivity, and there are no structural abnormalities shown by neuroimaging which are specific for epilepsy. Functional imaging (FI) has developed as a physiologic tool with anatomic sensitivity, and SPECT has been promoted as a FI technique because of its potentially wide availability. However, SPECT is early in its development and its clinical utility for epilepsy still has to be demonstrated. To understand this role of SPECT, consideration must be given to the pathophysiology of epilepsy, brain physiology, types of seizure, epileptic syndromes, and the SPECT technique itself. 44 refs., 2 tabs.

  19. Single photon light detector for deep ocean applications

    Energy Technology Data Exchange (ETDEWEB)

    Matsuno, S.; Babson, J.; Learned, J.G.; O' Connor, D.; Grieder, P.K.F.; Kitamura, T.; Mitsui, K.; Ohashi, Y.; Okada, A.; Clem, J.

    1989-03-15

    We have developed a single photon sensitive light detector module which can be operated in the ocean to a depth of 5000 m. It was designed primarily to be used as a Cherenkov light detector in conjunction with the DUMAND (Deep Underwater Muon And Neutrino Detector) experiment. After calibration in the laboratory, seven detectors, assembled in a vertical string geometry, have been operated simultaneously in the deep ocean off the coast of the island of Hawaii. Cosmic ray muons have been recorded successfully at dephts ranging from 2000 to 4000 m. The results have demonstrated the capability of the detector; it fulfills the specifications required for the modules to be used in a deep ocean muon and neutrino detector.

  20. Single photon light detector for deep ocean applications

    Science.gov (United States)

    Matsuno, S.; Babson, J.; Learned, J. G.; O'Connor, D.; Grieder, P. K. F.; Kitamura, T.; Mitsui, K.; Ohashi, Y.; Okada, A.; Clem, J.; Webster, M.; Wilson, C.

    1989-03-01

    We have developed a single photon sensitive light detector module which can be operated in the ocean to a depth of 5000 m. It was designed primarily to be used as a Cherenkov light detector in conjunction with the DUMAND (Deep Underwater Muon And Neutrino Detector) experiment. After calibration in the laboratory, seven detectors, assembled in a vertical string geometry, have been operated simultaneously in the deep ocean off the coast of the island of Hawaii. Cosmic ray muons have been recorded successfully at depths ranging from 2000 to 4000 m. The results have demonstrated the capability of the detector; it fulfills the specifications required for the modules to be used in a deep ocean muon and neutrino detector.

  1. Single-photon avalanche photodiodes with integrated quenching resistor

    Energy Technology Data Exchange (ETDEWEB)

    Mazzillo, M. [STMicroelectronics, IMS R and D Stradale Primosole 50, 95121 Catania (Italy)], E-mail: massimo.mazzillo@st.com; Condorelli, G.; Piazza, A.; Sanfilippo, D.; Valvo, G.; Carbone, B.; Fallica, G. [STMicroelectronics, IMS R and D Stradale Primosole 50, 95121 Catania (Italy); Billotta, S.; Belluso, M.; Bonanno, G. [INAF-Osservatorio Astrofisico di Catania, Via Santa Sofia 78, 95123 Catania (Italy); Pappalardo, A.; Cosentino, L.; Finocchiaro, P. [INFN-Laboratori Nazionali del Sud, Via Santa Sofia 64, 95125 Catania (Italy)

    2008-06-21

    In this paper we present the results of the first electrical and optical characterization performed on STMicroelectronics new photosensor technology based on silicon single-photon avalanche photodiodes (SPAD). On the prospective of the design and the manufacturing of large-area silicon photomultipliers to be used as photodetectors for nuclear medicine imaging applications, we have modified our previous SPAD technology by means of the integration of a high-value quenching resistor to the photodiode. Moreover, an appropriate antireflective coating layer and the reduction of the quasi-neutral region thickness above the thin junction depletion layer have been introduced in the process flow of the device to enhance its spectral response in blue and near ultraviolet wavelength ranges. High gain, low leakage currents, low dark noise, very good quantum detection efficiency in blue-near UV ranges and a good linearity of the photodiode response to the incident luminous flux are the main characterization results.

  2. Optical precursors from classical waves to single photons

    CERN Document Server

    Chen, JF; Loy, MMT; Du, Shengwang

    2013-01-01

    Ever since Einstein’s special relativity in 1905, the principle of invariant light speed in vacuum has been attracting attention from a wide range of disciplines. How to interpret the principle of light speed? Is light referred to continuous light, or light pulse with definite boundaries? Recent discovery of superluminal medium triggered vigorous discussion within the Physics community. Can communication via such “superluminal channel” break the speed limit and thus violate causality principle? Or, will a single photon, which is not governed by classical laws of Physics, tend to break the speed limit? To solve these problems, in this Brief we bring in optical precursor, the theoretical works for which started as early as 1914. This is a typical optical phenomenon combining wave propagation theory and light-wave interaction. Both theory and experimental works are covered in this Brief. The study of precursor verifies that the effective information carried by light pulses can never exceed the speed of lig...

  3. Custom single-photon avalanche diode with integrated front-end for parallel photon timing applications.

    Science.gov (United States)

    Cammi, C; Panzeri, F; Gulinatti, A; Rech, I; Ghioni, M

    2012-03-01

    Emerged as a solid state alternative to photo multiplier tubes (PMTs), single-photon avalanche diodes (SPADs) are nowadays widely used in the field of single-photon timing applications. Custom technology SPADs assure remarkable performance, in particular a 10 counts/s dark count rate (DCR) at low temperature, a high photon detection efficiency (PDE) with a 50% peak at 550 nm and a 30 ps (full width at half maximum, FWHM) temporal resolution, even with large area devices, have been obtained. Over the past few years, the birth of novel techniques of analysis has led to the parallelization of the measurement systems and to a consequent increasing demand for the development of monolithic arrays of detectors. Unfortunately, the implementation of a multidimensional system is a challenging task from the electrical point of view; in particular, the avalanche current pick-up circuit, used to obtain the previously reported performance, has to be modified in order to enable high parallel temporal resolution, while minimizing the electrical crosstalk probability between channels. In the past, the problem has been solved by integrating the front-end electronics next to the photodetector, in order to reduce the parasitic capacitances and consequently the filtering action on the current signal of the SPAD, leading to an improvement of the timing jitter at higher threshold. This solution has been implemented by using standard complementary metal-oxide-semiconductor (CMOS) technologies, which, however, do not allow a complete control on the SPAD structure; for this reason the intrinsic performance of CMOS SPADs, such as DCR, PDE, and afterpulsing probability, are worse than those attainable with custom detectors. In this paper, we propose a pixel architecture, which enables the development of custom SPAD arrays in which every channel maintains the performance of the best single photodetector. The system relies on the integration of the timing signal pick-up circuit next to the

  4. Experimental realization of a low-noise heralded single-photon source.

    Science.gov (United States)

    Brida, G; Degiovanni, I P; Genovese, M; Migdall, A; Piacentini, F; Polyakov, S V; Berchera, I Ruo

    2011-01-17

    We present a heralded single-photon source with a much lower level of unwanted background photons in the output channel by using the herald photon to control a shutter in the heralded channel. The shutter is implemented using a simple field programable gate array controlled optical switch.

  5. Experimental open-air quantum key distribution with a single-photon source

    Energy Technology Data Exchange (ETDEWEB)

    Alleaume, R [Laboratoire de Photonique Quantique et Moleculaire, UMR 8537 du CNRS, ENS Cachan, 61 avenue du President Wilson, 94235 Cachan Cedex (France); Treussart, F [Laboratoire de Photonique Quantique et Moleculaire, UMR 8537 du CNRS, ENS Cachan, 61 avenue du President Wilson, 94235 Cachan Cedex (France); Messin, G [Laboratoire Charles Fabry de l' Institut d' Optique, UMR 8501 du CNRS, F-91403 Orsay (France); Dumeige, Y [Laboratoire de Photonique Quantique et Moleculaire, UMR 8537 du CNRS, ENS Cachan, 61 avenue du President Wilson, 94235 Cachan Cedex (France); Roch, J-F [Laboratoire de Photonique Quantique et Moleculaire, UMR 8537 du CNRS, ENS Cachan, 61 avenue du President Wilson, 94235 Cachan Cedex (France); Beveratos, A [Laboratoire Charles Fabry de l' Institut d' Optique, UMR 8501 du CNRS, F-91403 Orsay (France); Brouri-Tualle, R [Laboratoire Charles Fabry de l' Institut d' Optique, UMR 8501 du CNRS, F-91403 Orsay (France); Poizat, J-P [Laboratoire Charles Fabry de l' Institut d' Optique, UMR 8501 du CNRS, F-91403 Orsay (France); Grangier, P [Laboratoire Charles Fabry de l' Institut d' Optique, UMR 8501 du CNRS, F-91403 Orsay (France)

    2004-07-01

    We describe the implementation of a quantum key distribution (QKD) system using a single-photon source, operating at night in open air. The single-photon source at the heart of the functional and reliable set-up relies on the pulsed excitation of a single nitrogen-vacancy colour centre in a diamond nanocrystal. We tested the effect of attenuation on the polarized encoded photons for inferring the longer distance performance of our system. For strong attenuation, the use of pure single-photon states gives measurable advantage over systems relying on weak attenuated laser pulses. The results are in good agreement with theoretical models developed to assess QKD security.

  6. Experimental open air quantum key distribution with a single photon source

    CERN Document Server

    Alleaume, R; Brouri-Tualle, R; Dumeige, Y; Messin, G; Poizat, J P; Roch, J F; Treussart, F; Alleaume, Romain; Beveratos, Alexios; Brouri-Tualle, Rosa; Dumeige, Yannick; Messin, Gaetan; Poizat, Jean-Philippe; Proxy, Philippe Grangier; Roch, Jean-Francois; Treussart, Francois; ccsd-00001148, ccsd

    2004-01-01

    We present a full implementation of a quantum key distribution (QKD) system with a single photon source, operating at night in open air. The single photon source at the heart of the functional and reliable setup relies on the pulsed excitation of a single nitrogen-vacancy color center in diamond nanocrystal. We tested the effect of attenuation on the polarized encoded photons for inferring longer distance performance of our system. For strong attenuation, the use of pure single photon states gives measurable advantage over systems relying on weak attenuated laser pulses. The results are in good agreement with theoretical models developed to assess QKD security.

  7. Time-division phase modulated single-photon interference in a Sagnac interferometer

    Institute of Scientific and Technical Information of China (English)

    WU Guang; ZHOU Chunyuan; ZENG Heping

    2003-01-01

    We introduce a stable, long-distance single- photon Sagnac interferometer, which has a balanced configuration to efficiently compensate phase drift caused by change of the fiber-optic path. By using time-division phase modulation, single-photon interference was realized at 1550 nm in a 5-km-long as well as 27-km-long Sagnac fiber loops, with a fringe visibility higher than 90% and long-term stability. The stable performance of the single-photon interference indicated that the time-division phase-modulated Sag- nac interferometer might readily lead to practical applications in single-photon routing and quantum cryptography.

  8. Single photon time transfer link model for GNSS satellites

    Science.gov (United States)

    Vacek, Michael; Michalek, Vojtech; Peca, Marek; Prochazka, Ivan; Blazej, Josef

    2015-05-01

    The importance of optical time transfer serving as a complement to traditional microwave links, has been attested for GNSSes and for scientific missions. Single photon time transfer (SPTT) is a process, allowing to compare (subtract) time readings of two distant clocks. Such a comparison may be then used to synchronize less accurate clock to a better reference, to perform clock characterization and calibration, to calculate mean time out of ensemble of several clocks, displaced in space. The single-photon time transfer is well established in field of space geodesy, being supported by passive retro-reflectors within space segment of five known GNSSes. A truly two-way, active terminals work aboard of Jason-2 (T2L2) - multiphoton operation, GNSS Beidou (Compass) - SPTT, and are going to be launched within recent ACES project (ELT) - SPTT, and GNSS GLONASS - multiphoton operation. However, there is still missing comprehensive theoretical model of two-way (using satellite receiver and retroreflector) SPTT link incorporating all crucial parameters of receiver (both ground and space segment receivers), transmitter, atmosphere effects on uplink and downlink path, influence of retroreflector. The input to calculation of SPTT link performance will be among others: link budget (distance, power, apertures, beam divergence, attenuation, scattering), propagating medium (atmosphere scintillation, beam wander, etc.), mutual Tx/Rx velocity, wavelength. The SPTT model will be evaluated without the properties of real components. These will be added in the further development. The ground-to-space SPTT link performance of typical scenarios are modeled. This work is a part of the ESA study "Comparison of optical time-transfer links."

  9. Interference with a quantum dot single-photon source and a laser at telecom wavelength

    Energy Technology Data Exchange (ETDEWEB)

    Felle, M. [Toshiba Research Europe Limited, Cambridge Research Laboratory, 208 Cambridge Science Park, Milton Road, Cambridge CB4 0GZ (United Kingdom); Centre for Advanced Photonics and Electronics, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0FA (United Kingdom); Huwer, J., E-mail: jan.huwer@crl.toshiba.co.uk; Stevenson, R. M.; Skiba-Szymanska, J.; Ward, M. B.; Shields, A. J. [Toshiba Research Europe Limited, Cambridge Research Laboratory, 208 Cambridge Science Park, Milton Road, Cambridge CB4 0GZ (United Kingdom); Farrer, I.; Ritchie, D. A. [Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Penty, R. V. [Centre for Advanced Photonics and Electronics, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0FA (United Kingdom)

    2015-09-28

    The interference of photons emitted by dissimilar sources is an essential requirement for a wide range of photonic quantum information applications. Many of these applications are in quantum communications and need to operate at standard telecommunication wavelengths to minimize the impact of photon losses and be compatible with existing infrastructure. Here, we demonstrate for the first time the quantum interference of telecom-wavelength photons from an InAs/GaAs quantum dot single-photon source and a laser; an important step towards such applications. The results are in good agreement with a theoretical model, indicating a high degree of indistinguishability for the interfering photons.

  10. Collective magnetic splitting in single-photon superradiance

    CERN Document Server

    Kong, Xiangjin

    2016-01-01

    In an ensemble of identical atoms, cooperative effects like sub- or superradiance may alter the decay rates and the energy of specific transitions may be shifted from the single-atom value by the so-called collective Lamb shift. So far, one has considered these effects in ensembles of two-level systems only. In this work we show that in a system with atoms or nuclei under the action of an external magnetic field, an additional, so far unaccounted for collective contribution to the level shifts appears that can amount to seizable deviations from the single-atom Zeeman or magnetic hyperfine splitting. We develop a formalism to describe single-photon superradiance in multi-level systems and quantify the parameter regime for which the collective Lamb shift leads to measurable deviations in the magnetic-field-induced splitting. In particular, we show that this effect should be observable in the nuclear magnetic hyperfine splitting in M\\"ossbauer nuclei embedded in thin-film x-ray cavities.

  11. Pulsed single-photon spectrograph by frequency-to-time mapping using chirped fiber Bragg gratings

    CERN Document Server

    Davis, Alex O C; Karpinski, Michal; Smith, Brian J

    2016-01-01

    A fiber-integrated spectrograph for single-photon pulses based upon frequency-to-time mapping, implemented by chromatic group delay dispersion (GDD), and precise temporally-resolved single photon counting is presented. A chirped fiber Bragg grating provides low-loss GDD mapping the frequency distribution of an input pulse onto the temporal envelope of the output pulse. Time-resolved detection with fast single-photon-counting modules enables the monitoring of the 825 nm to 835 nm wavelength range with nearly uniform efficiency with 55 pm resolution (24 GHz at 830 nm). To demonstrate the versatility of this technique spectral interference of heralded single photons and the joint spectral intensity distribution of a photon-pair source are measured. This approach to single-photon-level spectral measurements provides a route to realize applications of time-frequency quantum optics at visible and near-infrared wavelengths, where multiple spectral channels must be simultaneously monitored.

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

    CERN Document Server

    Daveau, Raphaël S; 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

    2016-01-01

    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 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 % $\\pm$ 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, ...

  13. 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,...

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

    CERN Document Server

    Madsen, K H; Liu, J; Javadi, A; Albrecht, S M; Yeo, I; Stobbe, S; Lodahl, P

    2014-01-01

    We demonstrate a single-photon collection efficiency of $(44.3\\pm2.1)\\%$ from a quantum dot in a low-Q mode of a photonic-crystal cavity with a single-photon purity of $g^{(2)}(0)=(4\\pm5)\\%$ and directly detect up to $962\\pm46$ kilocounts per second on a single-photon detector. The high collection efficiency is found to be broadband, as is confirmed 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 of up to $0.77\\pm0.19$ ns. Our work demonstrates that photonic crystals provide a very promising platform for highly integrated generation of coherent single photons including the efficient outcoupling of the photons from the photonic chip.

  15. 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.

  16. Controlling Single-Photon Transport along an Optical Waveguide by using a Three-Level Atom

    Institute of Scientific and Technical Information of China (English)

    TIAN Wei; CHEN Bin; XU Wei-Dong

    2012-01-01

    We theoretically investigate the single-photon transport properties in an optical waveguide embedded with a V-type three-level atom (VTLA) based on symmetric and asymmetric couplings between the photon and the VTLA.Our numerical results show that the transmission spectrum of the incident photon can be well controlled by virtue of both symmetric and asymmetric coupling interactions.A multifrequency photon attenuator is realized by controlling the asymmetric coupling interactions.Furthermore,the influences of dissipation of the VTLA for the realistic physical system on single-photon transport properties are also analyzed.

  17. Probing the Hotspot Interaction Length in NbN Nanowire Superconducting Single-Photon Detectors

    CERN Document Server

    Renema, J J; Wang, Q; van Exter, M P; Fiore, A; de Dood, M J A

    2016-01-01

    We measure the maximal distance at which two absorbed photons can jointly trigger a detection event in NbN nanowire superconducting single photon detector (SSPD) microbridges by comparing the one-photon and two-photon efficiency of bridges of different overall lengths, from 0 to 400 nm. We find a length of $23 \\pm 2$ nm. This value is in good agreement with to size of the quasiparticle cloud at the time of the detection event.

  18. High Speed Travelling Wave Single-Photon Detectors With Near-Unity Quantum Efficiency

    CERN Document Server

    Pernice, W; Minaeva, O; Li, M; Goltsman, G N; Sergienko, A V; Tang, H X

    2011-01-01

    Ultrafast, high quantum efficiency single photon detectors are among the most sought-after elements in modern quantum optics and quantum communication. Close-to-unity photon detection efficiency is essential for scalable measurement-based quantum computation, quantum key distribution, and loophole-free Bell experiments. However, imperfect modal matching and finite photon absorption rates have usually limited the maximum attainable detection efficiency of single photon detectors. Here we demonstrate a superconducting nanowire detector atop nanophotonic waveguides and achieve single photon detection efficiency up to 94% at telecom wavelengths. Our detectors are fully embedded in a scalable, low loss silicon photonic circuit and provide ultrashort timing jitter of 18ps at multi-GHz detection rates. Exploiting this high temporal resolution we demonstrate ballistic photon transport in silicon ring resonators. The direct implementation of such a detector with high quantum efficiency, high detection speed and low ji...

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

    Science.gov (United States)

    Hirvonen, Liisa M.; Barber, Matthew J.; Suhling, Klaus

    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.

  20. Superconducting nanowire single photon detectors for quantum information and communications

    CERN Document Server

    Wang, Zhen; Fujiwara, Mikio

    2010-01-01

    Superconducting nanowire single photon detectors (SNSPD or SSPD) are highly promising devices in the growing field of quantum information and communications technology. We have developed a practical SSPD system with our superconducting thin films and devices fabrication, optical coupling packaging, and cryogenic technology. The SSPD system consists of six-channel SSPD devices and a compact Gifford-McMahon (GM) cryocooler, and can operate continuously on 100 V ac power without the need for any cryogens. The SSPD devices were fabricated from high-quality niobium nitride (NbN) ultra-thin films that were epitaxially grown on single-crystal MgO substrates. The packaged SSPD devices were temperature stabilized to 2.96 K +/- 10 mK. The system detection efficiency for an SSPD device with an area of 20x20 $\\mu m^2$ was found to be 2.6% and 4.5% at wavelengths of 1550 and 1310 nm, respectively, at a dark count rate of 100 c/s, and a jitter of 100 ps full width at half maximum (FWHM). We also performed ultra-fast BB84 q...

  1. Simulating and Optimising Quantum Thermometry Using Single Photons

    Science.gov (United States)

    Tham, W. K.; Ferretti, H.; Sadashivan, A. V.; Steinberg, A. M.

    2016-12-01

    A classical thermometer typically works by exchanging energy with the system being measured until it comes to equilibrium, at which point the readout is related to the final energy state of the thermometer. A recent paper noted that with a quantum thermometer consisting of a single spin/qubit, temperature discrimination is better achieved at finite times rather than once equilibration is essentially complete. Furthermore, preparing a qubit thermometer in a state with quantum coherence instead of an incoherent one improves its sensitivity to temperature differences. Implementing a recent proposal for efficiently emulating an arbitrary quantum channel, we use the quantum polarisation state of individual photons as models of “single-qubit thermometers” which evolve for a certain time in contact with a thermal bath. We investigate the optimal thermometer states for temperature discrimination, and the optimal interaction times, confirming that there is a broad regime where quantum coherence provides a significant improvement. We also discuss the more practical question of thermometers composed of a finite number of spins/qubits (greater than one), and characterize the performance of an adaptive protocol for making optimal use of all the qubits.

  2. Single-shot gradient-assisted photon echo electronic spectroscopy.

    Science.gov (United States)

    Harel, Elad; Fidler, Andrew F; Engel, Gregory S

    2011-04-28

    Two-dimensional electronic spectroscopy (2D ES) maps the electronic structure of complex systems on a femtosecond time scale. While analogous to multidimensional NMR spectroscopy, 2D optical spectroscopy differs significantly in its implementation. Yet, 2D Fourier spectroscopies still require point-by-point sampling of the time delay between two pulses responsible for creating quantum coherence among states. Unlike NMR, achieving the requisite phase stability at optical frequencies between these pulse pairs remains experimentally challenging. Nonetheless, 2D optical spectroscopy has been successfully demonstrated by combining passive and active phase stabilization along with precise control of optical delays and long-term temperature stability, although the widespread adoption of 2D ES has been significantly hampered by these technical challenges. Here, we exploit an analogy to magnetic resonance imaging (MRI) to demonstrate a single-shot method capable of acquiring the entire 2D spectrum in a single laser shot using only conventional optics. Unlike point-by-point sampling protocols typically used to record 2D spectra, this method, which we call GRadient-Assisted Photon Echo (GRAPE) spectroscopy, largely eliminates phase errors while reducing the acquisition time by orders of magnitude. By incorporating a spatiotemporal encoding of the nonlinear polarization along the excitation frequency axis of the 2D spectrum, GRAPE spectroscopy achieves no loss in signal while simultaneously reducing overall noise. Here, we describe the principles of GRAPE spectroscopy and discuss associated experimental considerations.

  3. Quantum interference between two single photons emitted by independently trapped atoms

    CERN Document Server

    Beugnon, J; Dingjan, J; Darquié, B; Messin, G; Browaeys, A; Grangier, P; Beugnon, Jerome; Jones, Matthew; Dingjan, Jos; Darqui\\'{e}, Benoit; Messin, Gaetan; Browaeys, Antoine; Grangier, Philippe

    2006-01-01

    When two indistinguishable single photons are fed into the two input ports of a beam splitter, the photons will coalesce and leave together from the same output port. This is a quantum interference effect, which occurs because the two possible paths where the photons leave in different output ports interfere destructively. This effect was first observed in parametric downconversion by Hong, Ou and Mandel, and then with single photons produced one after the other by the same quantum emitter. With the recent development of quantum information, a lot of attention has been devoted to this coalescence effect as a resource for quantum data processing using linear optics techniques. To ensure the scalability of schemes based on these ideas, it is crucial that indistinguishable photons are emitted by a collection of synchronized, but otherwise independent sources. In this paper, we demonstrate the quantum interference of two single photons emitted by two independently trapped single atoms, bridging the gap towards th...

  4. Life, evolution, and the pursuit of single photon sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Bitensky, M.W.; Whalen, M.M.; Torney, D.C. (Los Alamos National Lab., NM (USA))

    1988-01-01

    Evolutionary forces have designed a large family of rod and cone photoreceptors, each member of which suits the lifestyle requirements and circadian patterns of a particular species. The three-segment architecture of signal transduction is conspicuous in the biochemistry of photoreceptors and supports their demonstrated properties of extreme sensitivity, low noise levels, extended dynamic range, and light adaptation. The designs elaborated by evolution reflect a gradual process of modification, with the sequential elaboration of layers of control and refinements in control. The end results of this long evolutionary labor are the functional efficiency and dynamic range that give the rod its utility. Our conceptual problems in deriving observed rod properties from the collective features of known rod gene products may well give way when we have learned more about the true composition and topology of the outer segment gene set and both bound and free nucleotide concentrations. The invertebrates have developed alternative solutions to the problems of photoreceptor sensitivity and wide dynamic range. The vertebrate rod represents a truly optimized way to capture and interpret low-intensity photon signals. One may anticipate, with some enthusiasm, those molecular and kinetic data that will permit an understanding of how cones differ from rods and how release from the requirement for single photon detection has shaped the design of this wavelength-specific companion photoreceptor. The utilization by evolution of the three-segment architecture of GTP-dependent signal transduction for other modalities of sensory perception, such as olfaction and gustation is certainly a reasonable and successful choice. 56 references.

  5. Design for an efficient single photon source based on a single quantum dot embedded in a parabolic solid immersion lens.

    Science.gov (United States)

    Devaraj, Vasanthan; Baek, Jongseo; Jang, Yudong; Jeong, Hyuk; Lee, Donghan

    2016-04-18

    We have designed a single photon emitter based on a single quantum dot embedded within a single mode parabolic solid immersion lens (pSIL) and a capping low-index pSIL. Numerical simulations predicted that the emitter performance should exhibit a high photon collection efficiency with excellent far-field emission properties, broadband operation, and good tolerance in its geometric (spatial configuration) parameters. Good geometric tolerance in a single-mode pSIL without yielding significant losses in the photon collection efficiency is advantageous for device fabrication. The low-index top pSIL layer provided this structure with a high photon collection efficiency, even in the case of a small numerical aperture (NA). Photon collection efficiencies of 64% and 78% were expected for NA values of 0.41 and 0.5, respectively. In addition to the benefits listed above, our combined pSIL design provided excellent broadband performance in a 100 nm range.

  6. Efficient single-mode photon-coupling device utilizing a nanofiber tip.

    Science.gov (United States)

    Chonan, Sho; Kato, Shinya; Aoki, Takao

    2014-04-24

    Single-photon sources are important elements in quantum optics and quantum information science. It is crucial that such sources be able to couple photons emitted from a single quantum emitter to a single propagating mode, preferably to the guided mode of a single-mode optical fiber, with high efficiency. Various photonic devices have been successfully demonstrated to efficiently couple photons from an emitter to a single mode of a cavity or a waveguide. However, efficient coupling of these devices to optical fibers is sometimes challenging. Here we show that up to 38% of photons from an emitter can be directly coupled to a single-mode optical fiber by utilizing the flat tip of a silica nanofiber. With the aid of a metallic mirror, the efficiency can be increased to 76%. The use of a silicon waveguide further increases the efficiency to 87%. This simple device can be applied to various quantum emitters.

  7. Quantum information-holding single-photon router based on spontaneous emission

    Science.gov (United States)

    Yan, GuoAn; Qiao, HaoXue; Lu, Hua; Chen, AiXi

    2017-09-01

    In this paper, we propose a single-photon router via the use of a four-level atom system coupled with two one-dimensional coupled-resonator waveguides. A single photon can be directed from one quantum channel into another by atomic spontaneous emission. The coherent resonance and the photonic bound states lead to the perfect reflection appearing in the incident channel. The fidelity of the atom is related to the magnitude of the coupling strength and can reach unit when the coupling strength matches g a = g b . This shows that the transfer of a single photon into another quantum channel has no influence on the fidelity at special points.

  8. 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...

  9. 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.

  10. Corpuscular Model of Two-Beam Interference and Double-Slit Experiments with Single Photons

    NARCIS (Netherlands)

    Jin, Fengping; Yuan, Shengjun; De Raedt, Hans; Michielsen, Kristel; Miyashita, Seiji

    2010-01-01

    We introduce an event-based corpuscular simulation model that reproduces the wave mechanical results of single-photon double-slit and two-beam interference experiments and (of a one-to-one copy of an experimental realization) of a single-photon interference experiment with a Fresnel biprism. The sim

  11. Corpuscular Model of Two-Beam Interference and Double-Slit Experiments with Single Photons

    NARCIS (Netherlands)

    Jin, Fengping; Yuan, Shengjun; De Raedt, Hans; Michielsen, Kristel; Miyashita, Seiji

    We introduce an event-based corpuscular simulation model that reproduces the wave mechanical results of single-photon double-slit and two-beam interference experiments and (of a one-to-one copy of an experimental realization) of a single-photon interference experiment with a Fresnel biprism. The

  12. 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.

  13. Quantum interference between two single photons emitted by independently trapped atoms.

    Science.gov (United States)

    Beugnon, J; Jones, M P A; Dingjan, J; Darquié, B; Messin, G; Browaeys, A; Grangier, P

    2006-04-06

    When two indistinguishable single photons are fed into the two input ports of a beam splitter, the photons will coalesce and leave together from the same output port. This is a quantum interference effect, which occurs because two possible paths-in which the photons leave by different output ports-interfere destructively. This effect was first observed in parametric downconversion (in which a nonlinear crystal splits a single photon into two photons of lower energy), then from two separate downconversion crystals, as well as with single photons produced one after the other by the same quantum emitter. With the recent developments in quantum information research, much attention has been devoted to this interference effect as a resource for quantum data processing using linear optics techniques. To ensure the scalability of schemes based on these ideas, it is crucial that indistinguishable photons are emitted by a collection of synchronized, but otherwise independent sources. Here we demonstrate the quantum interference of two single photons emitted by two independently trapped single atoms, bridging the gap towards the simultaneous emission of many indistinguishable single photons by different emitters. Our data analysis shows that the observed coalescence is mainly limited by wavefront matching of the light emitted by the two atoms, and to a lesser extent by the motion of each atom in its own trap.

  14. Telecommunications-band heralded single photons from a silicon nanophotonic chip

    CERN Document Server

    Davanco, Marcelo; Shehata, Andrea Bahgat; Tosi, Alberto; Agha, Imad; Assefa, Solomon; Xia, Fengnian; Green, William M J; Mookherjea, Shayan; Srinivasan, Kartik

    2012-01-01

    We demonstrate heralded single photon generation in a CMOS-compatible silicon nanophotonic device. The strong modal confinement and slow group velocity provided by a coupled resonator optical waveguide (CROW) produced a large four-wave-mixing nonlinearity coefficient gamma_eff ~4100 W^-1 m^-1 at telecommunications wavelengths. Spontaneous four-wave-mixing using a degenerate pump beam at 1549.6 nm created photon pairs at 1529.5 nm and 1570.5 nm with a coincidence-to-accidental ratio exceeding 20. A photon correlation measurement of the signal (1529.5 nm) photons heralded by the detection of the idler (1570.5 nm) photons showed antibunching with g^(2)(0) = 0.19 \\pm 0.03. The demonstration of a single photon source within a silicon platform holds promise for future integrated quantum photonic circuits.

  15. 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.

  16. Photon Statistics of a Single Atom Intracavity EIT-Kerr System

    CERN Document Server

    Rebic, S; Tan, S M

    2002-01-01

    We explore the photon statistics of light emitted from a system comprising a single four--level atom strongly coupled to a high-finesse optical cavity mode which is driven by a coherent laser field. In the weak driving regime this system is found to exhibit a photon blockade effect. For intermediate driving strengths we find a sudden change in the photon statistics of the light emitted from the cavity. Photon antibunching switches to photon bunching over a very narrow range of intracavity photon number. It is proven that this sudden change in photon statistics occurs due to the existence of robust quantum interference of transitions between the dressed states of the atom-cavity system. Furthermore, it is shown that the strong photon bunching is a nonclassical effect for certain values of driving field strength, violating classical inequalities for field correlations.

  17. Quick single-photon detector with many avalanche photo diodes working on the time division

    Institute of Scientific and Technical Information of China (English)

    Jian Peng; Yifei Fu; Li Yao; Xudong Shang; Zhixin Lu; Bojun Yang; Li Yu

    2008-01-01

    Due to the limit of response speed of the present single-photon detector, the code rate is still too low to come into practical use for the present quantum key distribution (QKD) system.A new idea is put up to design a quick single-photon detector.This quick single-photon detector is composed of a multi-port optic-fiber splitter and many avalanche photo diodes (APDs).Au of the ports with APDs work on the time division and cooperate with a logic discriminating and deciding unit driven by the clock signal.The operation frequency lies on the number N of ports, and can reach N times of the conventional single-photon detector.The single-photon prompt detection can come true for high repetition-rate pulses.The applying of this detector will largely raise the code rate of the QKD, and boost the commercial use.

  18. 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....

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

    DEFF Research Database (Denmark)

    Madsen, Marta Arcari

    The main goal of the project has been to realize an efficient source of coherent single photons by coupling a self-assembled quantum dot to a photonic crystal waveguide. Such a source would have a wide range of applications in the field of quantum information processing. By studying the coupling...... 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...

  20. How a single photon can mediate entanglement between two others

    Science.gov (United States)

    de Lima Bernardo, Bertúlio

    2016-10-01

    We describe a novel quantum information protocol, which probabilistically entangles two distant photons that have never interacted. Different from the entanglement swapping protocol, which requires two pairs of maximally entangled photons as the input states, as well as a Bell-state measurement (BSM), the present scheme only requires three photons: two to be entangled and another to mediate the correlation, and no BSM, in a process that we call "entanglement mediation". Furthermore, in analyzing the paths of the photons in our arrangement, we conclude that one of them, the mediator, exchanges information with the two others simultaneously, which seems to be a new quantum-mechanical feature.

  1. 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.

    2017-03-01

    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.

  2. On-chip interference of single photons from an embedded quantum dot and an external laser

    Energy Technology Data Exchange (ETDEWEB)

    Prtljaga, N., E-mail: n.prtljaga@sheffield.ac.uk; Bentham, C.; O' Hara, J.; Royall, B.; Wilson, L. R.; Skolnick, M. S.; Fox, A. M. [Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH (United Kingdom); Clarke, E. [Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield S1 3JD (United Kingdom)

    2016-06-20

    In this work, we demonstrate the on-chip two-photon interference between single photons emitted by a single self-assembled InGaAs quantum dot and an external laser. The quantum dot is embedded within one arm of an air-clad directional coupler which acts as a beam-splitter for incoming light. Photons originating from an attenuated external laser are coupled to the second arm of the beam-splitter and then combined with the quantum dot photons, giving rise to two-photon quantum interference between dissimilar sources. We verify the occurrence of on-chip Hong-Ou-Mandel interference by cross-correlating the optical signal from the separate output ports of the directional coupler. This experimental approach allows us to use a classical light source (laser) to assess in a single step the overall device performance in the quantum regime and probe quantum dot photon indistinguishability on application realistic time scales.

  3. 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

    2017-01-01

    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. PMID:28294155

  4. Quantum Optics with Quantum Dots in Photonic Wires: Basics and Application to “Ultrabright” Single Photon Sources

    DEFF Research Database (Denmark)

    Gérard, J. M.; Claudon, J.; Bleuse, J.

    2011-01-01

    We review recent experimental and theoretical results, which highlight the strong interest of the photonic wire (PW) geometry for quantum optics experiments with solid-state emitters, and for quantum optoelectronic devices. By studying single InAs QDs embedded within single-mode cylindrical GaAs PW......, we have noticeably observed a very strong (16 fold) inhibition of their spontaneous emission rate in the thin-wire limit, and a nearly perfect funnelling of their spontaneous emission into the guided mode for larger PWs. We present a novel single -photon-source based on the emission of a quantum dot...... embedded in an engineered PW, comprising a tapered tip so as to control the radiation pattern, and an integrated hybrid bottom mirror. Unlike microcavity-based devices, this source displays for the first time simultaneously a record-high efficiency (0.73 photon per pulse) and a very low g(2) parameter...

  5. Single-Photon Emission at Liquid Nitrogen Temperature from a Single InAs/GaAs Quantum Dot

    Institute of Scientific and Technical Information of China (English)

    DOU Xiu-Ming; SUN Bao-Quan; CHANG Xiu-Ying; XIONG Yong-Hua; HUANG She-Song; NI Hai-Qiao; NIU Zhi-Chuan

    2008-01-01

    We report on the single photon emission from single InAs/GaAs self-assembled Stranski-Krastanow quantum dots up to 80 K under pulsed and continuous wave excitations. At temperature 80 K, the second-order correlation function at zero time delay, g(2)(0), is measured to be 0.422 for pulsed excitation. At the same temperature under continuous wave excitation, the photon antibunching effect is observed. Thus, our experimental results demonstrate a promising potential application of self-assembled InAs/GaAs quantum dots in single photon emission at liquid nitrogen temperature.

  6. Three-dimensional photonic crystals created by single-step multi-directional plasma etching.

    Science.gov (United States)

    Suzuki, Katsuyoshi; Kitano, Keisuke; Ishizaki, Kenji; Noda, Susumu

    2014-07-14

    We fabricate 3D photonic nanostructures by simultaneous multi-directional plasma etching. This simple and flexible method is enabled by controlling the ion-sheath in reactive-ion-etching equipment. We realize 3D photonic crystals on single-crystalline silicon wafers and show high reflectance (>95%) and low transmittance (<-15dB) at optical communication wavelengths, suggesting the formation of a complete photonic bandgap. Moreover, our method simply demonstrates Si-based 3D photonic crystals that show the photonic bandgap effect in a shorter wavelength range around 0.6 μm, where further fine structures are required.

  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 Atomic Sorting: Isotope Separation with Maxwell's Demon

    CERN Document Server

    Raizen, M G; Jerkins, M

    2010-01-01

    Isotope separation is one of the grand challenges of modern society and holds great potential for basic science, medicine, energy, and defense. We consider here a new and general approach to isotope separation. The method is based on an irreversible change of the mass-to-magnetic moment ratio of a particular isotope in an atomic beam, followed by deflection in a magnetic field gradient. The underlying mechanism is a reduction of the entropy of the beam by the information of a single-scattered photon for each atom that is separated. We numerically simulate isotope separation for a range of examples. The first class of atoms we consider are those that have zero magnetic moment in their ground electronic state. A laser induces an irreversible transition to a metastable state, followed by magnetic deflection. The second (larger) class of atoms we consider are those that have a magnetic moment in their ground state. The magnetic stretch-state is deflected in one zone of a magnetic field gradient, followed by a las...

  9. Optimized Superconducting Nanowire Single Photon Detectors to Maximize Absorptance

    CERN Document Server

    Csete, Maria; Szenes, Andras; Banhelyi, Balazs; Csendes, Tibor; Szabo, Gabor

    2015-01-01

    Dispersion characteristics of four types of superconducting nanowire single photon detectors, nano-cavity-array- (NCA-), nano-cavity-deflector-array- (NCDA-), nano-cavity-double-deflector-array- (NCDDA-) and nano-cavity-trench-array- (NCTA-) integrated (I-A-SNSPDs) devices was optimized in three periodicity intervals commensurate with half-, three-quarter- and one SPP wavelength. The optimal configurations capable of maximizing NbN absorptance correspond to periodicity dependent tilting in S-orientation (90{\\deg} azimuthal orientation). In NCAI-A-SNSPDs absorptance maxima are reached at the plasmonic Brewster angle (PBA) due to light tunneling. The absorptance maximum is attained in a wide plasmonic-pass-band in NCDAI_1/2*lambda-A, inside a flat-plasmonic-pass-band in NCDAI_3/4*lambda-A and inside a narrow plasmonic-band in NCDAI_lambda-A. In NCDDAI_1/2*lambda-A bands of strongly-coupled cavity and plasmonic modes cross, in NCDDAI_3/4*lambda-A an inverted-plasmonic-band-gap develops, while in NCDDAI_lambda-A ...

  10. Stress-first single photon emission computed myocardial perfusion imaging

    Science.gov (United States)

    Aquino, C I; Scarano, M; Squame, F; Casaburi, G; Nori, S L; Pace, L

    2016-01-01

    Background Myocardial perfusion imaging (MPI) with single photon emission tomography (SPET) is widely used in coronary artery disease evaluation. Recently major dosimetric concerns have arisen. The aim of this study was to evaluate if a pre-test scoring system could predict the results of stress SPET MPI, thus avoiding two radionuclide injections. Methods All consecutive patients (n=309) undergoing SPET MPI during the first 6 months of 2014 constituted the study group. The scoring system is based on these characteristics: age >65 years (1 point), diabetes (2 points), typical chest pain (2 points), congestive heart failure (3 points), abnormal ECG (4 points), male gender (4 points), and documented previous CAD (5 points). The patients were divided on the basis of the prediction score into 3 classes of risk for an abnormal stress-first protocol. Results An abnormal stress SPET MPI was present in 7/31 patients (23%) with a low risk score, in 24/90 (27%) with an intermediate score risk, and in 124/188 (66%) with an high score risk. ROC curve analysis showed good prediction of abnormal stress MPI. Conclusions Our results suggest an appropriate use of a pre-test clinical prediction formula of abnormal stress MPI in a routine clinical setting. PMID:27896227

  11. 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.

  12. On single-photon ultraviolet ablation of polymeric materials

    Science.gov (United States)

    Cain, Stephen R.; Burns, F. C.; Otis, C. E.

    1992-05-01

    The nature of uv ablation of organic polymers is discussed in terms of a pseudo-zeroth-order rate law of the form dx/dt = k0e-(Eact/kT), where Eact is assumed to be the strength of the weakest bonds in the polymer and T is the local temperature increase from the incident laser pulse. Equations derived from previous models that assumed nonthermal photodecomposition were duplicated from this photothermal model. Even for the simple case of single-photon absorption, nonideal behavior is affected by radiationless decay, pulse length, and thermal diffusion. These effects were probed. Results indicated that thermal diffusion may have a significant effect on the threshold fluence and to some degree on the shape of the etch depth versus fluence curve. Absorption dynamics (saturation and radiationless decay) appear to be the dominant factor in determining the functional dependence of etch depth on fluence. As a result of competition between absorption saturation and radiationless decay, the penetration depth is intensity dependent. High fluence as well as short temporal pulses (subnanosecond) penetrate more deeply into the polymer than predicted by simple Beer's law absorption. The apparent existence of an optimum pulse length, for a given absorbing system, is another result of the absorption dynamics.

  13. 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)

  14. Single Chargino Production with R-Parity Lepton Number Violation in Photon-Photon Collisions

    Institute of Scientific and Technical Information of China (English)

    YIN Xi; MA Wen-Gan; WAN Lang-Hui; JIANG Yi; HAN Liang

    2001-01-01

    We examine the process γγ→ x+ - at photon-photon collider in the minimal supersymmetric standard model with R-parity violation,where all the one-loop diagrams are considered.We mainly discuss the effects of bilinear breaking terms,and conclude that their contributions may be important compared with trilinear terms.Our results show that the events of this process could be detectable at photon-photon colliders,if the values of the parameters are favorable.``

  15. Room temperature triggered single-photon source in the near infrared

    Energy Technology Data Exchange (ETDEWEB)

    Wu, E [Laboratoire de Photonique Quantique et Moleculaire, UMR CNRS 8537, Ecole Normale Superieure de Cachan (France); Rabeau, J R [Department of Physics, Macquarie University, Sydney, New South Wales 2109 (Australia); Roger, G [Laboratoire Charles Fabry de l' Institut d' Optique, UMR CNRS 8501, Palaiseau (France); Treussart, F [Laboratoire de Photonique Quantique et Moleculaire, UMR CNRS 8537, Ecole Normale Superieure de Cachan (France); Zeng, H [State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China (China); Grangier, P [Laboratoire Charles Fabry de l' Institut d' Optique, UMR CNRS 8501, Palaiseau (France); Prawer, S [Centre of Excellence for Quantum Computer Technology and Quantum Communications Victoria, School of Physics, University of Melbourne, Victoria 3010 (Australia); Roch, J-F [Laboratoire de Photonique Quantique et Moleculaire, UMR CNRS 8537, Ecole Normale Superieure de Cachan (France)

    2007-12-15

    We report the realization of a solid-state triggered single-photon source with narrow emission in the near infrared at room temperature. It is based on the photoluminescence of a single nickel-nitrogen NE8 colour centre in a chemical vapour deposited diamond nanocrystal. Stable single-photon emission has been observed in the photoluminescence under both continuous-wave and pulsed excitations. The realization of this source represents a step forward in the application of diamond-based single-photon sources to quantum key distribution (QKD) under practical operating conditions.

  16. Wave properties of Fibonacci-sequence photonic crystals containing single-negative materials

    Science.gov (United States)

    Chen, Mei-Soong; Wu, Chien-Jang; Yang, Tzong-Jer; Fuh, Andy Ying-Guey

    2013-08-01

    Electromagnetic wave properties of a Fibonacci-sequence photonic crystal (FSPC) made of single-negative materials are theoretically investigated. It is found that, in the oblique incidence, such a kind of photonic crystal exhibits additional photonic bands or dips in the vicinity of either magnetic plasma frequency or electric plasma frequency. The additional photonic bands or dips corresponding to magnetic plasma frequency occur only for the TE wave, whereas those corresponding to electric plasma frequency occur only for the TM wave. In addition, we find that there exist omnidiretional gaps in such a single-negative FSPC.

  17. Performance of a superconducting single photon detector with nano-antenna

    Institute of Scientific and Technical Information of China (English)

    Zhang Chao; Jiao Rong-Zhen

    2012-01-01

    The performance of single-photon detectors can be enhanced by using nano-antenna.The characteristics of the superconducting nano-wire single-photon detector with cavity plus anti-reflect coating and specially designed nanoantenna is analysed.The photon collection efficiency of the detector is enhanced without damaging the detector's speed,thus getting rid of the dilemma of speed and efficiency.The characteristics of nano-antenna are discussed,such as the position and the effect of the active area,and the best result is given.The photon collection efficiency is increased by 92 times compared with that of existing detectors.

  18. Bright quantum dot single photon source based on a low Q defect cavity

    DEFF Research Database (Denmark)

    Maier, Sebastian; Gold, Peter; Forchel, A.

    2014-01-01

    The quasi-planar single photon source presented in this paper shows an extraction efficiency of 42% without complex photonic resonator geometries or lithography steps as well as a high purity with a g2(0) value of 0.023.......The quasi-planar single photon source presented in this paper shows an extraction efficiency of 42% without complex photonic resonator geometries or lithography steps as well as a high purity with a g2(0) value of 0.023....

  19. Large conditional single-photon cross-phase modulation

    CERN Document Server

    Beck, Kristin M; Duan, Yiheng; Vuletić, Vladan

    2015-01-01

    Deterministic optical quantum logic requires a nonlinear quantum process that alters the phase of a quantum optical state by $\\pi$ through interaction with only one photon. Here, we demonstrate a large conditional cross-phase modulation between a signal field, stored inside an atomic quantum memory, and a control photon that traverses a high-finesse optical cavity containing the atomic memory. This approach avoids fundamental limitations associated with multimode effects for traveling optical photons. We measure a conditional cross-phase shift of up to $\\pi/3$ between the retrieved signal and control photons, and confirm deterministic entanglement between the signal and control modes by extracting a positive concurrence. With a moderate improvement in cavity finesse, our system can reach a coherent phase shift of $\\pi$ at low loss, enabling deterministic and universal photonic quantum logic.

  20. 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.

  1. Photonic gaps in one dimensional cylindrical photonic crystal that incorporates single negative materials

    Science.gov (United States)

    El-Naggar, Sahar A.

    2017-01-01

    In this article, we theoretically study electromagnetic waves that propagate in one-dimensional cylindrical photonic crystals (1DCPC) containing single negative materials. We examine the optical properties of three gaps namely; the zero-effective phase (zero- ϕ), the zero-permittivity (zero- ɛ) and the zero-permeability (zero- μ). We calculate the optical reflectance for transverse electric(magnetic) TE(TM) polarizations using the transfer matrix method in the cylindrical coordinates. We study the effect of azimuthal mode number ( m) and the starting radius on these gaps. The results show that the zero- μ (zero- ɛ) gap is found for TE(TM) polarization at frequency where μ( ɛ) changes its sign for m ≥ 1. The width of the gap increases by decreasing the starting radius or by increasing m, whereas the zero- ϕ gap remains invariant. In addition, we present a brief design of 1D-CPC that has a polarization-independent wide gap especially for high azimuthal mode number ( m > 2). Our results can help improve the performance of microwave devices independent of the source wave polarization.

  2. Photon efficiency optimization in time-correlated single photon counting technique for fluorescence lifetime imaging systems.

    Science.gov (United States)

    Turgeman, Lior; Fixler, Dror

    2013-06-01

    In time-correlated single photon counting (TCSPC) systems, the maximum signal throughput is limited by the occurrence of pile-up and other effects. In many biological applications that exhibit high levels of fluorescence intensity (FI), pile-up-related distortions yield serious distortions in the fluorescence lifetime (FLT) calculation as well as significant decrease in the signal-to-noise ratio (SNR). Recent developments that allow the use of high-repetition-rate light sources (in the range of 50-100 MHz) in fluorescence lifetime imaging (FLIM) experiments enable minimization of pile-up-related distortions. However, modern TCSPC configurations that use high-repetition-rate excitation sources for FLIM suffer from dead-time-related distortions that cause unpredictable distortions of the FI signal. In this study, the loss of SNR is described by F- value as it is typically done in FLIM systems. This F-value describes the relation of the relative standard deviation in the estimated FLT to the relative standard deviation in FI measurements. Optimization of the F-value allows minimization of signal distortion, as well as shortening of the acquisition time for certain samples. We applied this method for Fluorescein, Rhodamine B, and Erythrosine fluorescent solutions that have different FLT values (4 ns, 1.67 ns, and 140 ps, respectively).

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

    Science.gov (United States)

    Ra, Young-Sik; Jacquard, Clément; Dufour, Adrien; Fabre, Claude; Treps, Nicolas

    2017-07-01

    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.

  4. Sine wave gating silicon single-photon detectors for multiphoton entanglement experiments

    Science.gov (United States)

    Zhou, Nan; Jiang, Wen-Hao; Chen, Luo-Kan; Fang, Yu-Qiang; Li, Zheng-Da; Liang, Hao; Chen, Yu-Ao; Zhang, Jun; Pan, Jian-Wei

    2017-08-01

    Silicon single-photon detectors (SPDs) are the key devices for detecting single photons in the visible wavelength range. Here we present high detection efficiency silicon SPDs dedicated to the generation of multiphoton entanglement based on the technique of high-frequency sine wave gating. The silicon single-photon avalanche diode components are acquired by disassembling 6 commercial single-photon counting modules (SPCMs). Using the new quenching electronics, the average detection efficiency of SPDs is increased from 68.6% to 73.1% at a wavelength of 785 nm. These sine wave gating SPDs are then applied in a four-photon entanglement experiment, and the four-fold coincidence count rate is increased by 30% without degrading its visibility compared with the original SPCMs.

  5. Wiring up pre-characterized single-photon emitters by laser lithography

    Science.gov (United States)

    Shi, Q.; Sontheimer, B.; Nikolay, N.; Schell, A. W.; Fischer, J.; Naber, A.; Benson, O.; Wegener, M.

    2016-08-01

    Future quantum optical chips will likely be hybrid in nature and include many single-photon emitters, waveguides, filters, as well as single-photon detectors. Here, we introduce a scalable optical localization-selection-lithography procedure for wiring up a large number of single-photon emitters via polymeric photonic wire bonds in three dimensions. First, we localize and characterize nitrogen vacancies in nanodiamonds inside a solid photoresist exhibiting low background fluorescence. Next, without intermediate steps and using the same optical instrument, we perform aligned three-dimensional laser lithography. As a proof of concept, we design, fabricate, and characterize three-dimensional functional waveguide elements on an optical chip. Each element consists of one single-photon emitter centered in a crossed-arc waveguide configuration, allowing for integrated optical excitation and efficient background suppression at the same time.

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

    Science.gov (United States)

    Kyriienko, Oleksandr; Sørensen, Anders S.

    2016-09-01

    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 connected to input-output waveguides. Using a classical drive on the upper transition, we find parameter space where a single photon control pulse incident on one of the cavities can be fully absorbed into hybridized excited states. This subsequently leads to series of quantum jumps in the upper manifold 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 count rate for large anharmonicity, and can be readily implemented using current technology.

  7. Bidirectional Mapping between a Biphoton Polarization State and a Single-Photon Two-Qubit State

    Institute of Scientific and Technical Information of China (English)

    LIN Qing

    2010-01-01

    @@ How to manipulate(operate or measure)single photons efficiently and simply is the basic problem in optical quantum information processing.We first present an efficient scheme to transform a biphoton polarization state to a corresponding single-photon state encoded by its polarization and spatial modes.This single-photon state carries both the information of the controlled and target photons.It will make the realization of bipartite positive-operator-valued measurements efficiently and simply.Moreover,the inverse transformation from the single-photon state back to the corresponding biphoton polarization state is also proposed.Using both the transformations,the realization of the arbitrary two-qubit unitary operation is simple with an M-Z interferometer.All the schemes are feasible with the current experimental technology.

  8. 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...

  9. 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.

  10. Single photon counting for space based quantum experiments

    Science.gov (United States)

    Chandrasekara, R.; Tang, Z. K.; Tan, Y. C.; Cheng, C.; Wildfeuer, C.; Ling, A.

    2015-05-01

    We present a software based control system for Geiger-mode avalanche photodiodes (GM-APDs) that enables constant photon detection efficiency irrespective of the diode's junction temperature. Furthermore, we demonstrate that this control system enables passively quenched GM-APDs to double the rate of photon detection events before saturation compared to the standard control method that fixes the junction temperature and applied bias voltage. We present data demonstrating the robustness of the GM-APD control system when tested in near-space conditions using a correlated photon pair source carried by a weather balloon to an altitude of 35.5 km.

  11. Two-Photon Exchange Corrections to Single Spin Asymmetry of Neutron and 3He

    Institute of Scientific and Technical Information of China (English)

    CHEN Dian-Yong; DONG Yu-Bing

    2011-01-01

    In a simple hadronic model, the two-photon exchange contributions to the single spin asymmetries for the nucleon and the 3He are estimated. The results show that the elastic contributions of two-photon exchange to the single spin asymmetries for the nucleon are rather small while those for the 3He are relatively large. Besides the strong angular dependence, the twophoton contributions to the single spin asymmetry for the 3He are very sensitive to the momentum transfer.

  12. Efficient single-photon source based on a deterministically fabricated single quantum dot - microstructure with backside gold mirror

    Science.gov (United States)

    Fischbach, Sarah; Kaganskiy, Arsenty; Tauscher, Esra Burcu Yarar; Gericke, Fabian; Thoma, Alexander; Schmidt, Ronny; Strittmatter, André; Heindel, Tobias; Rodt, Sven; Reitzenstein, Stephan

    2017-07-01

    We present an efficient broadband single-photon source which is fabricated by a flip-chip gold-bonding technique and in-situ electron beam lithography. The device comprises a single InGaAs quantum dot that is centered at the bottom of a monolithic mesa structure and located above a gold mirror for enhanced photon-extraction efficiency. We show a photon-extraction efficiency of ηex t=(18 ±2 ) % into a numerical aperture of 0.4 and a high suppression of multi-photon events from this source with g(2 )(0 )=0.015 ±0.009 . Our deterministic device with a backside gold mirror can be combined with electrical contacts and piezo-tuning capabilities in future refinements, which represents an important step towards a spectrally tunable plug-and-play quantum-light source with broadband enhancement for photonic quantum networks.

  13. 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.

  14. Producing high fidelity single photons with optimal brightness via waveguided parametric down-conversion

    OpenAIRE

    Laiho K.; Cassemiro K.N.; Silberhorn C.

    2009-01-01

    Parametric down-conversion (PDC) offers the possibility to control the fabrication of non-Gaussian states such as Fock states. However, in conventional PDC sources energy and momentum conservation introduce strict frequency and photon number correlations, which impact the fidelity of the prepared state. In our work we optimize the preparation of single-photon Fock states from the emission of waveguided PDC via spectral filtering. We study the effect of correlations via photon number resolving...

  15. Single-mode and single-polarization photonics with anchored-membrane waveguides.

    Science.gov (United States)

    Chiles, Jeff; Fathpour, Sasan

    2016-08-22

    An integrated photonic platform with "anchored-membrane" structures, the T-Guide, is proposed, numerically investigated, fabricated and characterized. These compact air-clad structures have high index contrast and are much more stable than prior membrane-type structures. Their semi-infinite geometry enables single-mode and single-polarization (SMSP) operation over unprecedented bandwidths. Modal simulations quantify this behavior, showing that an SMSP window of 2.75 octaves (1.2-8.1 μm) is feasible for silicon T-Guides, spanning almost the entire transparency range of silicon. Dispersion engineering for T-Guides yields broad regions of anomalous group velocity dispersion, rendering them a promising platform for nonlinear applications such as wideband frequency conversion. Cut-back measurements of fabricated silicon T-guides at λ = 3.64 μm show low propagation losses of 1.75 ± 0.3 dB/cm.

  16. Single-mode and single-polarization photonics with anchored-membrane waveguides

    CERN Document Server

    Chiles, Jeff

    2016-01-01

    An integrated photonic platform with anchored-membrane structures, the T-Guide, is proposed and numerically investigated. These compact air-clad structures have high index contrast and are much more stable than prior membrane-type structures. Their semi-infinite geometry enables single-mode and single-polarization (SMSP) operation over unprecedented bandwidths. Modal simulations quantify this behavior, showing that an SMSP window of 2.75 octaves (1.2 - 8.1 {\\mu}m) is feasible for silicon T-Guides, spanning almost the entire transparency range of silicon. Dispersion engineering for T-Guides yields broad regions of anomalous group velocity dispersion, rendering them a promising platform for nonlinear applications, such as wideband frequency conversion.

  17. Multigate single-photon detection and timing discrimination with an InGaAs/lnP avalanche photodiode.

    Science.gov (United States)

    Zhou, Chunyuan; Wu, Guang; Zeng, Heping

    2006-03-10

    Multigate detection of single photons at 1550 nm is achieved by using capacitor-balanced InGaAs/InP avalanche photodiodes, with which we experimentally demonstrate the efficient discrimination of single-photon timing by counting single-photon clicks and the corresponding afterpulses within the multiple gates. Results show that the technique of multigate detection is a practical method for the single-photon timing information process.

  18. p-Shell Rabi-flopping and single photon emission in an InGaAs/GaAs quantum dot

    Science.gov (United States)

    Ester, P.; Lackmann, L.; Hübner, M. C.; Michaelis de Vasconcellos, S.; Zrenner, A.; Bichler, M.

    2008-04-01

    Very clean single photon emission from a single InGaAs/GaAs quantum dot is demonstrated by the use of a coherent optical state preparation. We present a concept for single photon emission, which uses p-shell Rabi-flopping followed by a sequence of relaxation and recombination. The proof of the (clean) single photon emission is performed by photon correlation measurements.

  19. Universal unitary gate for single-photon spinorbit ququart states

    CERN Document Server

    Slussarenko, Sergei; Piccirillo, Bruno; Marrucci, Lorenzo; Santamato, Enrico

    2009-01-01

    The recently demonstrated possibility of entangling opposite values of the orbital angular momentum (OAM) of a photon with its spin enables the realization of nontrivial one-photon spinorbit ququart states, i.e., four-dimensional photon states for quantum information purposes. Hitherto, however, an optical device able to perform arbitrary unitary transformations on such spinorbit photon states has not been proposed yet. In this work we show how to realize such a ``universal unitary gate'' device, based only on existing optical technology, and describe its operation. Besides the quantum information field, the proposed device may find applications wherever an efficient and convenient manipulation of the combined OAM and spin of light is required.

  20. 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...

  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.......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. Generation of single photons with highly tunable wave shape from a cold atomic quantum memory

    CERN Document Server

    Farrera, Pau; Albrecht, Boris; Ho, Melvyn; Chávez, Matías; Teo, Colin; Sangouard, Nicolas; de Riedmatten, Hugues

    2016-01-01

    We report on a single photon source with highly tunable photon shape based on a cold ensemble of Rubidium atoms. We follow the DLCZ scheme to implement an emissive quantum memory, which can be operated as a photon pair source with controllable delay. We find that the temporal wave shape of the emitted read photon can be precisely controlled by changing the shape of the driving read pulse. We generate photons with temporal durations varying over three orders of magnitude up to 10 {\\mu}s without a significant change of the read-out efficiency. We prove the non-classicality of the emitted photons by measuring their antibunching, showing near single photon behavior at low excitation probabilities. We also show that the photons are emitted in a pure state by measuring unconditional autocorrelation functions. Finally, to demonstrate the usability of the source for realistic applications, we create ultra-long single photons with a rising exponential or doubly peaked wave shape which are important for several quantum...

  3. Effective Single Photon Decay Mode of Positronium Decay via Electroweak Interactions

    CERN Document Server

    Pérez-Ríos, Jesús

    2015-01-01

    We consider the decay of positronium to a neutrino-antineutrino accompanied by a single photon. Since the neutrino pair go undetected, this appears as a single photon decay of positronium. These decay channel are mediated through the exchange of the massive $W$ and $Z$ vector bosons of the electroweak interaction. After summing over the various neutrino channels, the standard model calculation yields the rate for such a single photon decay process of $\\Gamma_{Ps \\rightarrow \\gamma}$ = 1.72 $\\times 10^{-19}$ s$^{-1}$.

  4. Matrix of integrated superconducting single-photon detectors with high timing resolution

    CERN Document Server

    Schuck, Carsten; Minaeva, Olga; Li, Mo; Gol'tsman, Gregory; Sergienko, Alexander V; Tang, Hong X

    2013-01-01

    We demonstrate a large grid of individually addressable superconducting single photon detectors on a single chip. Each detector element is fully integrated into an independent waveguide circuit with custom functionality at telecom wavelengths. High device density is achieved by fabricating the nanowire detectors in traveling wave geometry directly on top of silicon-on-insulator waveguides. Our superconducting single-photon detector matrix includes detector designs optimized for high detection efficiency, low dark count rate and high timing accuracy. As an example, we exploit the high timing resolution of a particularly short nanowire design to resolve individual photon round-trips in a cavity ring-down measurement of a silicon ring resonator.

  5. Single photon delayed feedback: a way to stabilize intrinsic quantum cavity electrodynamics.

    Science.gov (United States)

    Carmele, Alexander; Kabuss, Julia; Schulze, Franz; Reitzenstein, Stephan; Knorr, Andreas

    2013-01-01

    We propose a scheme to control cavity quantum electrodynamics in the single photon limit by delayed feedback. In our approach a single emitter-cavity system, operating in the weak coupling limit, can be driven into the strong coupling-type regime by an external mirror: The external loop produces Rabi oscillations directly connected to the electron-photon coupling strength. As an expansion of typical cavity quantum electrodynamics, we treat the quantum correlation of external and internal light modes dynamically and demonstrate a possible way to implement a fully quantum mechanical time-delayed feedback. Our theoretical approach proposes a way to experimentally feedback control quantum correlations in the single photon limit.

  6. 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...... resonant tunneling diodes. A single photon detection efficiency of 2.1%+/- 0.1% at 685 nm was measured corresponding to an internal quantum efficiency of 14%. The devices are simple to fabricate, robust, and show promise for large absorption area single photon detectors based on quantum dot structures....

  7. Beyond single-photon localization at the edge of a Photonic Band Gap

    CERN Document Server

    Nikolopoulos, G M; Nikolopoulos, Georgios M.

    2000-01-01

    We study spontaneous emission in an atomic ladder system, with bothtransitions coupled near-resonantly to the edge of a photonic band gapcontinuum. The problem is solved through a recently developed technique andleads to the formation of a ``two-photon+atom'' bound state with fractionalpopulation trapping in both upper states. In the long-time limit, the atom canbe found excited in a superposition of the upper states and a ``direct''two-photon process coexists with the stepwise one. The sensitivity of theeffect to the particular form of the density of states is also explored.

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

    DEFF Research Database (Denmark)

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

    2013-01-01

    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......  factor, meaning that efficient coupling from the QD to the guided mode is obtained over a broad spectral range of ~ 50-100 nm. [4] This means that spectral alignment between the emitter line and a narrow cavity line is not required, which represents a huge practical advantage in the fabrication...

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

    DEFF Research Database (Denmark)

    Daveau, Raphaël Sura

    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......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...... the characterization of single quantum dots. The second method, evanescent coupling from a tapered waveguide to a microber, demonstrates a chip-to-ber coupling eciency exceeding 80 % in passive re- ection measurements. The characterization of quantum dots from this device establishes a ber-coupled source eciency of 15...

  10. Special properties of single-photon optical fiber sensor for security needs

    Science.gov (United States)

    Zyczkowski, M.; Szustakowski, M.; Karol, M.; Markowski, Piotr; Napierala, M. S.

    2014-10-01

    The rules of quantum physics are now fairly well understood and indisputable. On the basis of these principles are built safety systems to guarantee unconditional security of data transmission. This is possible due to the random behavior of the measured photon. Theorems of quantum mechanics are used currently in Quantum Key Distribution systems to determine the encryption key of cryptographic systems. Sending the single photons through the interferometer it is possible to determine the probability distribution of a photon detection at a given output depending on the interferometer imbalance. The use of single photon interference allows reduce the probability of detection of the transmission line protection. Additionally it provides high safety of transmitted information and minor disturbances. The quantum sensor can be a device which allows effectively protect transmission lines. In this paper we demonstrate measurement results of the using single-photon interferometers in security systems and potential capabilities use of such sensors.

  11. Corpuscular model of two-beam interference and double-slit experiments with single photons

    CERN Document Server

    Jin, Fengping; De Raedt, Hans; Michielsen, Kristel; Miyashita, Seiji

    2010-01-01

    We introduce an event-based corpuscular simulation model that reproduces the wave mechanical results of single-photon double slit and two-beam interference experiments and (of a one-to-one copy of an experimental realization) of a single-photon interference experiment with a Fresnel biprism. The simulation comprises models that capture the essential features of the apparatuses used in the experiment, including the single-photon detectors recording individual detector clicks. We demonstrate that incorporating in the detector model, simple and minimalistic processes mimicking the memory and threshold behavior of single-photon detectors is sufficient to produce multipath interference patterns. These multipath interference patterns are built up by individual particles taking one single path to the detector where they arrive one-by-one. The particles in our model are not corpuscular in the standard, classical physics sense in that they are information carriers that exchange information with the apparatuses of the ...

  12. Few-photon imaging at 1550 nm using a low-timing-jitter superconducting nanowire single-photon detector

    CERN Document Server

    Zhou, H; You, L; Chen, S; Zhang, W; Wu, J; Wang, Z; Xie, X

    2015-01-01

    We demonstrated a laser depth imaging system based on the time-correlated single-photon counting technique, which was incorporated with a low-jitter superconducting nanowire single-photon detector (SNSPD), operated at the wavelength of 1550 nm. A sub-picosecond time-bin width was chosen for photon counting, resulting in a discrete noise of less than one/two counts for each time bin under indoor/outdoor daylight conditions, with a collection time of 50 ms. Because of the low-jitter SNSPD, the target signal histogram was significantly distinguishable, even for a fairly low retro-reflected photon flux. The depth information was determined directly by the highest bin counts, instead of using any data fitting combined with complex algorithms. Millimeter resolution depth imaging of a low-signature object was obtained, and more accurate data than that produced by the traditional Gaussian fitting method was generated. Combined with the intensity of the return photons, three-dimensional reconstruction overlaid with re...

  13. 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.

  14. 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 0.89 ...

  15. 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, a...

  16. Fluorescence lifetime imaging by time-correlated single-photon counting

    NARCIS (Netherlands)

    Becker, W.; Bergmann, A.; Hink, M.A.; Konig, K.; Benndorf, K.; Biskup, C.

    2004-01-01

    We present a time-correlated single photon counting (TCPSC) technique that allows time-resolved multi-wavelength imaging in conjunction with a laser scanning microscope and a pulsed excitation source. The technique is based on a four-dimensional histogramming process that records the photon density

  17. 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...... of consecutively emitted photons up to 98.5%....

  18. 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%.

  19. 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%.

  20. 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.

  1. Practical single-photon-assisted remote state preparation with non-maximally entanglement

    Science.gov (United States)

    Wang, Dong; Huang, Ai-Jun; Sun, Wen-Yang; Shi, Jia-Dong; Ye, Liu

    2016-08-01

    Remote state preparation (RSP) and joint remote state preparation (JRSP) protocols for single-photon states are investigated via linear optical elements with partially entangled states. In our scheme, by choosing two-mode instances from a polarizing beam splitter, only the sender in the communication protocol needs to prepare an ancillary single-photon and operate the entanglement preparation process in order to retrieve an arbitrary single-photon state from a photon pair in partially entangled state. In the case of JRSP, i.e., a canonical model of RSP with multi-party, we consider that the information of the desired state is split into many subsets and in prior maintained by spatially separate parties. Specifically, with the assistance of a single-photon state and a three-photon entangled state, it turns out that an arbitrary single-photon state can be jointly and remotely prepared with certain probability, which is characterized by the coefficients of both the employed entangled state and the target state. Remarkably, our protocol is readily to extend to the case for RSP and JRSP of mixed states with the all optical means. Therefore, our protocol is promising for communicating among optics-based multi-node quantum networks.

  2. 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...

  3. Ultrafast room temperature single-photon source from nanowire-quantum dots.

    Science.gov (United States)

    Bounouar, S; Elouneg-Jamroz, M; Hertog, M den; Morchutt, C; Bellet-Amalric, E; André, R; Bougerol, C; Genuist, Y; Poizat, J-Ph; Tatarenko, S; Kheng, K

    2012-06-13

    Epitaxial semiconductor quantum dots are particularly promising as realistic single-photon sources for their compatibility with manufacturing techniques and possibility to be implemented in compact devices. Here, we demonstrate for the first time single-photon emission up to room temperature from an epitaxial quantum dot inserted in a nanowire, namely a CdSe slice in a ZnSe nanowire. The exciton and biexciton lines can still be resolved at room temperature and the biexciton turns out to be the most appropriate transition for single-photon emission due to a large nonradiative decay of the bright exciton to dark exciton states. With an intrinsically short radiative decay time (≈300 ps) this system is the fastest room temperature single-photon emitter, allowing potentially gigahertz repetition rates.

  4. 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...

  5. 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,...

  6. A gallium nitride single-photon source operating at 200 K.

    Science.gov (United States)

    Kako, Satoshi; Santori, Charles; Hoshino, Katsuyuki; Götzinger, Stephan; Yamamoto, Yoshihisa; Arakawa, Yasuhiko

    2006-11-01

    Fundamentally secure quantum cryptography has still not seen widespread application owing to the difficulty of generating single photons on demand. Semiconductor quantum-dot structures have recently shown great promise as practical single-photon sources, and devices with integrated optical cavities and electrical-carrier injection have already been demonstrated. However, a significant obstacle for the application of commonly used III-V quantum dots to quantum-information-processing schemes is the requirement of liquid-helium cryogenic temperatures. Epitaxially grown gallium nitride quantum dots embedded in aluminium nitride have the potential for operation at much higher temperatures. Here, we report triggered single-photon emission from gallium nitride quantum dots at temperatures up to 200 K, a temperature easily reachable with thermo-electric cooling. Gallium nitride quantum dots also open a new wavelength region in the blue and near-ultraviolet portions of the spectrum for single-photon sources.

  7. 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...

  8. Effect of Background Noise on the Photon Statistics of Triggered Single Molecules

    Institute of Scientific and Technical Information of China (English)

    XIAO Lian-Tuan; ZHAO Yan-Ting; HUANG Tao; ZHAO Jian-Ming; YIN Wang-Bao; JIA Suo-Tang

    2004-01-01

    @@ We theoretically derive exact expressions for Mandel's Q parameter of the triggered single molecular source, which is inferred from the probabilities PRS(n) using the recorded of each photon detection event based on Hanbury Brown and Twiss detection. The real triggered source is recognized as an ideal single photon source with a Poissonian statistics background. How to decease the background and to increase the efficiency are discussed. It is established that the sub-Poissonian statistics formation can be determined by comparing the measured QRS of the real single triggered molecular with QC of the Poissonian source containing the same mean photons. By this method, we also give an efficient way to measure signal-to-background ratios of triggered single photons.

  9. Quantum Secret Sharing Protocol between Multiparty and Multiparty with Single Photons and Unitary Transformations

    Institute of Scientific and Technical Information of China (English)

    YAN Feng-Li; GAO Ting; LI You-Cheng

    2008-01-01

    @@ We propose a scheme of quantum secret sharing between Alice's group and Bob's group with single photons and unitary transformations. In the protocol, one member in Alice's group prepares a sequence of single photons in one of four different states, while other members directly encode their information on the sequence of single photons via unitary operations; after that, the last member sends the sequence of single photons to Bob's group.Then Bob's, except for the last one, do work similarly. Finally the last member in Bob's group measures the qubits. If the security of the quantum channel is guaranteed by some tests, then the qubit states sent by the last member of Alice's group can be used as key bits for secret sharing. It is shown that this scheme is safe.

  10. 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...

  11. High-fidelity transfer and storage of photon states in a single nuclear spin

    Science.gov (United States)

    Yang, Sen; Wang, Ya; Rao, D. D. Bhaktavatsala; Hien Tran, Thai; Momenzadeh, Ali S.; Markham, M.; Twitchen, D. J.; Wang, Ping; Yang, Wen; Stöhr, Rainer; Neumann, Philipp; Kosaka, Hideo; Wrachtrup, Jörg

    2016-08-01

    Long-distance quantum communication requires photons and quantum nodes that comprise qubits for interaction with light and good memory capabilities, as well as processing qubits for the storage and manipulation of photons. Owing to the unavoidable photon losses, robust quantum communication over lossy transmission channels requires quantum repeater networks. A necessary and highly demanding prerequisite for these networks is the existence of quantum memories with long coherence times to reliably store the incident photon states. Here we demonstrate the high-fidelity (˜98%) coherent transfer of a photon polarization state to a single solid-state nuclear spin that has a coherence time of over 10 s. The storage process is achieved by coherently transferring the polarization state of a photon to an entangled electron-nuclear spin state of a nitrogen-vacancy centre in diamond. The nuclear spin-based optical quantum memory demonstrated here paves the way towards an absorption-based quantum repeater network.

  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.

    2017-01-01

    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. PMID:28349960

  14. Multiple-output microwave single-photon source using superconducting circuits with longitudinal and transverse couplings

    Science.gov (United States)

    Wang, Xin; Miranowicz, Adam; Li, Hong-Rong; Nori, Franco

    2016-11-01

    Single-photon devices at microwave frequencies are important for applications in quantum information processing and communication in the microwave regime. In this work we describe a proposal of a multioutput single-photon device. We consider two superconducting resonators coupled to a gap-tunable qubit via both its longitudinal and transverse degrees of freedom. Thus, this qubit-resonator coupling differs from the coupling in standard circuit quantum-electrodynamic systems described by the Jaynes-Cummings model. We demonstrate that an effective quadratic coupling between one of the normal modes and the qubit can be induced and this induced second-order nonlinearity is much larger than that for conventional Kerr-type systems exhibiting photon blockade. Assuming that a coupled normal mode is resonantly driven, we observe that the output fields from the resonators exhibit strong sub-Poissonian photon-number statistics and photon antibunching. Contrary to previous studies on resonant photon blockade, the first-excited state of our device is a pure single-photon Fock state rather than a polariton state, i.e., a highly hybridized qubit-photon state. In addition, it is found that the optical state truncation caused by the strong qubit-induced nonlinearity can lead to an entanglement between the two resonators, even in their steady state under the Markov approximation.

  15. A quantum phase switch between a single solid-state spin and a photon

    Science.gov (United States)

    Sun, Shuo; Kim, Hyochul; Solomon, Glenn S.; Waks, Edo

    2016-06-01

    Interactions between single spins and photons are essential for quantum networks and distributed quantum computation. Achieving spin-photon interactions in a solid-state device could enable compact chip-integrated quantum circuits operating at gigahertz bandwidths. Many theoretical works have suggested using spins embedded in nanophotonic structures to attain this high-speed interface. These proposals implement a quantum switch where the spin flips the state of the photon and a photon flips the spin state. However, such a switch has not yet been realized using a solid-state spin system. Here, we report an experimental realization of a spin-photon quantum switch using a single solid-state spin embedded in a nanophotonic cavity. We show that the spin state strongly modulates the polarization of a reflected photon, and a single reflected photon coherently rotates the spin state. These strong spin-photon interactions open up a promising direction for solid-state implementations of high-speed quantum networks and on-chip quantum information processors using nanophotonic devices.

  16. Nonlinear modifications of photon correlations via controlled single and double Rydberg blockade

    Science.gov (United States)

    Liu, Yi-Mou; Tian, Xue-Dong; Yan, Dong; Zhang, Yan; Cui, Cui-Li; Wu, Jin-Hui

    2015-04-01

    We study the optical response of cold rubidium atoms driven into the four-level Y configuration exhibiting two high Rydberg levels in the regime of electromagnetically induced transparency (EIT). Atoms excited to either Rydberg level interact with each other just via self-blockade potentials (I) or also via cross blockade potentials (II). Numerical results show a few interesting quantum phenomena on the transmitted properties of a weak probe field owing to controlled single and double Rydberg blockade. In case (I), it is viable to switch between single-photon outputs with vanishing (invariable) two-photon (three-photon) correlation and photon-pair outputs with vanishing (invariable) three-photon (two-photon) correlation. Such output switch can be easily done by modulating frequencies and intensities of two strong coupling fields to create a degenerate EIT window or two separated EIT windows. In case (II), we find that two-photon and three-photon correlations decrease together at a degenerate EIT window center while increasing together between two separated EIT windows. Such consistent changes are observed because both correlations are modified by the identical polarizability degradation though depending on single and double Rydberg blockade, respectively.

  17. A quantum phase switch between a single solid-state spin and a photon.

    Science.gov (United States)

    Sun, Shuo; Kim, Hyochul; Solomon, Glenn S; Waks, Edo

    2016-06-01

    Interactions between single spins and photons are essential for quantum networks and distributed quantum computation. Achieving spin-photon interactions in a solid-state device could enable compact chip-integrated quantum circuits operating at gigahertz bandwidths. Many theoretical works have suggested using spins embedded in nanophotonic structures to attain this high-speed interface. These proposals implement a quantum switch where the spin flips the state of the photon and a photon flips the spin state. However, such a switch has not yet been realized using a solid-state spin system. Here, we report an experimental realization of a spin-photon quantum switch using a single solid-state spin embedded in a nanophotonic cavity. We show that the spin state strongly modulates the polarization of a reflected photon, and a single reflected photon coherently rotates the spin state. These strong spin-photon interactions open up a promising direction for solid-state implementations of high-speed quantum networks and on-chip quantum information processors using nanophotonic devices.

  18. Quantum Frequency Conversion of Single-Photon States by Three and Four-Wave Mixing

    DEFF Research Database (Denmark)

    Raymer, Michael G.; Reddy, Dileep V.; Andersen, Lasse Mejling

    2013-01-01

    Three- or four-wave mixing can convert a single-photon wave packet to a new frequency. By tailoring the shapes of the pump(s), one can achieve add/drop functionality for different temporally orthogonal wave packets.......Three- or four-wave mixing can convert a single-photon wave packet to a new frequency. By tailoring the shapes of the pump(s), one can achieve add/drop functionality for different temporally orthogonal wave packets....

  19. Single photon quantum non-demolition in the presence of inhomogeneous broadening

    OpenAIRE

    Greentree, Andrew D.; Beausoleil, R. G.; Hollenberg, L. C. L.; Munro, W. J.; Nemoto, Kae; Prawer, S.; Spiller, T. P.

    2009-01-01

    Electromagnetically induced transparency (EIT) has been often 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 realisations in any medium will have to contend with inhomogeneous broadening. Here we reappraise an earlier scheme [Munro \\textit{et al.} Phys. Rev. A \\textbf{71}, 033819 (2005...

  20. Reach of Environmental Influences on the Indistinguishability of Single Photons from Quantum Dots

    CERN Document Server

    Huber, Tobias; Föger, Daniel; Solomon, Glenn; Weihs, Gregor

    2015-01-01

    In this letter, we present a detailed, all optical study of the influence of different excitation schemes on the indistinguishability of single photons from a single InAs quantum dot. For this study, we measure the Hong-Ou-Mandel interference of consecutive photons from the spontaneous emission of an InAs quantum dot state under various excitation schemes and different excitation conditions and give a comparison.

  1. Fast Excitation and Photon Emission of a Single-Atom-Cavity System

    OpenAIRE

    Bochmann, J.; Muecke, M.; Langfahl-Klabes, G.; Erbel, C; Weber, B.; Specht, H. P.; Moehring, D L; Rempe, G.

    2008-01-01

    We report on the fast excitation of a single atom coupled to an optical cavity using laser pulses that are much shorter than all other relevant processes. The cavity frequency constitutes a control parameter that allows the creation of single photons in a superposition of two tunable frequencies. Each photon emitted from the cavity thus exhibits a pronounced amplitude modulation determined by the oscillatory energy exchange between the atom and the cavity. Our technique constitutes a versatil...

  2. Optimal coupling of entangled photons into single-mode optical fibers

    CERN Document Server

    Andrews, R; Sarkar, S; Sarkar, Sarben

    2004-01-01

    We present a consistent multimode theory that describes the coupling of single photons generated by collinear Type-I parametric down-conversion into single-mode optical fibers. We have calculated an analytic expression for the fiber diameter which maximizes the pair photon count rate. For a given focal length and wavelength, a lower limit of the fiber diameter for satisfactory coupling is obtained.

  3. Derivation of the density matrix of a single photon produced in parametric down-conversion

    Science.gov (United States)

    Kolenderski, Piotr; Wasilewski, Wojciech

    2009-07-01

    We discuss an effective numerical method of density matrix determination of fiber coupled single photon generated in process of spontaneous parametric down conversion in type I noncollinear configuration. The presented theory has been successfully applied in case of source utilized to demonstrate the experimental characterization of spectral state of single photon, what was reported in Wasilewski, Kolenderski, and Frankowski [Phys. Rev. Lett. 99, 123601 (2007)].

  4. 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.

  5. On-chip electrically controlled routing of photons from a single quantum dot

    Energy Technology Data Exchange (ETDEWEB)

    Bentham, C.; Coles, R. J.; Royall, B.; O' Hara, J.; Prtljaga, N.; Fox, A. M.; Skolnick, M. S.; Wilson, L. R. [Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH (United Kingdom); Itskevich, I. E., E-mail: I.Itskevich@hull.ac.uk [School of Engineering, University of Hull, Hull HU6 7RX (United Kingdom); Clarke, E. [Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield S1 3JD (United Kingdom)

    2015-06-01

    Electrical control of on-chip routing of photons emitted by a single InAs/GaAs self-assembled quantum dot (SAQD) is demonstrated in a photonic crystal cavity-waveguide system. The SAQD is located inside an H1 cavity, which is coupled to two photonic crystal waveguides. The SAQD emission wavelength is electrically tunable by the quantum-confined Stark effect. When the SAQD emission is brought into resonance with one of two H1 cavity modes, it is preferentially routed to the waveguide to which that mode is selectively coupled. This proof of concept provides the basis for scalable, low-power, high-speed operation of single-photon routers for use in integrated quantum photonic circuits.

  6. Guided wave technology for a telecom wavelength heralded single photon source

    CERN Document Server

    Alibart, O; Ostrowsky, D B; Baldi, P; Alibart, Olivier; Tanzilli, Sebastien; Ostrowsky, Daniel Barry; Baldi, Pascal

    2004-01-01

    We report on a guided wave heralded photon source based on the creation of non-degenerate photon pairs by spontaneous parametric down conversion in a Periodically Poled Lithium Niobate waveguide. Using the signal photon at 1310 nm as a trigger, a gated detection process permits announcing the arrival of single photons at 1550 nm at the output of a single mode optical fiber with the best probability to date of 0.38. The multi-photon emission probability is reduced by a factor of 10 compared to poissonian light sources. Relying on guided wave technologies such as integrated optics and fiber optics components, our source offers stability, compactness and efficiency and can serve as a paradigm for guided wave devices applied to quantum communication and computation using existing telecom networks.

  7. 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.

  8. A high-fidelity photon gun: intensity-squeezed light from a single molecule

    CERN Document Server

    Chu, Xiao-Liu; Sandoghdar, Vahid

    2016-01-01

    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 metallo-dielectric antenna applied to an organic molecule, we demonstrate the most regular stream of single photons reported to date. Measured intensity fluctuations reveal 2.2 dB squeezing limited by our detection efficiency, equivalent to 6.2 dB intensity squeezing right after the antenna.

  9. 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.

  10. 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...... avenue for efficient (up to 42% demonstrated) and pure (g2(0) value of 0.023) single-photon emission....... 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...

  11. 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.

  12. Numerical analysis of Ino.53Gao.47As/InP single photon avalanche diodes

    Institute of Scientific and Technical Information of China (English)

    Zhou Peng; Li Chun-Fei; Liao Chang-Jun; Wei Zheng-Jun; Yuan Shu-Qiong

    2011-01-01

    A rigorous theoretical model for In0.53Ga0.47As/InP single photon avalanche diode is utilized to investigate the dependences of single photon quantum efficiency and dark count probability on structure and operation condition. In the model, low field impact ionizations in charge and absorption layers are allowed, while avalanche breakdown can occur only in the multiplication layer. The origin of dark counts is discussed and the results indicate that the dominant mechanism that gives rise to dark counts depends on both device structure and operating condition. When the multiplication layer is thicker than a critical thickness or the temperature is higher than a critical value, generation-recombination in the absorption layer is the dominative mechanism; otherwise band-to-band tunneling in the multiplication layer dominates the dark counts. The thicknesses of charge and multiplication layers greatly affect the dark count and the peak single photon quantum efficiency and increasing the multiplication layer width may reduce the dark count probability and increase the peak single photon quantum efficiency. However, when the multiplication layer width exceeds 1 μm, the peak single photon quantum efficiency increases slowly and it is finally saturated at the quantum efficiency of the single photon avalanche diodes.

  13. Single photon transport in two waveguides chirally coupled by a quantum emitter.

    Science.gov (United States)

    Cheng, Mu-Tian; Ma, Xiao-San; Zhang, Jia-Yan; Wang, Bing

    2016-08-22

    We investigate single photon transport in two waveguides coupled to a two-level quantum emitter (QE). With the deduced analytical scattering amplitudes, we show that under condition of the chiral coupling between the QE and the photon in the two waveguides, the QE can play the role of ideal quantum router to redirect a single photon incident from one waveguide into the other waveguide with a probability of 100% in the ideal condition. The influences of cross coupling between two waveguides and dissipations on the routing are also shown.

  14. Surface acoustic wave regulated single photon emission from a coupled quantum dot-nanocavity system

    Science.gov (United States)

    Weiß, M.; Kapfinger, S.; Reichert, T.; Finley, J. J.; Wixforth, A.; Kaniber, M.; Krenner, H. J.

    2016-07-01

    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 fSAW ≃ 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(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.

  15. Design of highly efficient metallo-dielectric patch antennas for single-photon emission.

    Science.gov (United States)

    Bigourdan, F; Marquier, F; Hugonin, J-P; Greffet, J-J

    2014-02-10

    Quantum emitters such as NV-centers or quantum dots can be used as single-photon sources. To improve their performance, they can be coupled to microcavities or nano-antennas. Plasmonic antennas offer an appealing solution as they can be used with broadband emitters. When properly designed, these antennas funnel light into useful modes, increasing the emission rate and the collection of single-photons. Yet, their inherent metallic losses are responsible for very low radiative efficiencies. Here, we introduce a new design of directional, metallo-dielectric, optical antennas with a Purcell factor of 150, a total efficiency of 74% and a collection efficiency of emitted photons of 99%.

  16. Single telecom photon heralding by wavelength multiplexing in an optical fiber

    Science.gov (United States)

    Lenhard, Andreas; Brito, José; Kucera, Stephan; Bock, Matthias; Eschner, Jürgen; Becher, Christoph

    2016-01-01

    We demonstrate the multiplexing of a weak coherent and a quantum state of light in a single telecommunication fiber. For this purpose, we make use of spontaneous parametric down conversion and quantum frequency conversion to generate photon pairs at 854 nm and the telecom O-band. The herald photon at 854 nm triggers a telecom C-band laser pulse. The telecom single photon (O-band) and the laser pulse (C-band) are combined and coupled to a standard telecom fiber. Low-background time correlation between the weak coherent and quantum signal behind the fiber shows successful multiplexing.

  17. 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.

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

    DEFF Research Database (Denmark)

    Kyriienko, Oleksandr; Sørensen, Anders Søndberg

    2016-01-01

    connected to input-output waveguides. Using a classical drive on the upper transition, we find parameter space where a single photon control pulse incident on one of the cavities can be fully absorbed into hybridized excited states. This subsequently leads to series of quantum jumps in the upper manifold...... 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...

  19. Nonclassical emission from single colloidal nanocrystals in a microcavity: a route towards room temperature single photon sources

    Energy Technology Data Exchange (ETDEWEB)

    Qualtieri, Antonio; Morello, Giovanni; Todaro, Maria T; Stomeo, Tiziana; Martiradonna, Luigi; De Giorgi, Milena; Cingolani, Roberto; De Vittorio, Massimo [National Nanotechnology Laboratory (NNL) of CNR-INFM, Distretto Tecnologico ISUFI, Universita del Salento, via per Arnesano, 73100 Lecce (Italy); Spinicelli, Piernicola; Bramati, Alberto; Hermier, Jean P [Laboratoire Kastler Brossel-Universite Paris 6, Ecole Normale Superieure et CNRS, UPMC case 74, 4 Place Jussieu, 75252 Paris Cedex 05 (France); Quelin, Xavier; Buil, Stephanie [Groupe d' etude de la Matiere Condensee, CNRS UMR8635, Universite de Versailles Saint Quentin, 45 avenue des Etats-Unis, 78035 Versailles Cedex (France)], E-mail: antonio.qualtieri@unile.it

    2009-03-15

    Secure quantum communication systems (QCS) based on the transmission of crucial information through single photons are among the most appealing frontiers for telecommunications, though their development is still hindered by the lack of cheap and bright single photon sources (SPSs) operating at room temperature (RT). In this paper, we show the occurrence of photon antibunching at RT from single colloidal CdSe/ZnS nanocrystals (NCs) inserted in a vertical microcavity. Moreover, by using high-resolution lithographic techniques, we conceived a general route for positioning single colloidal quantum dots in the microcavity. The findings and the technique presented here can be considered a first step towards the development of SPS devices operating at RT.

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

    NARCIS (Netherlands)

    Melai, J.; Salm, C.; Schmitz, J.; Smits, S.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 fa

  1. On-demand semiconductor single-photon source with near-unity indistinguishability

    CERN Document Server

    He, Yu-Ming; Wei, Yu-Jia; Wu, Dian; Atatüre, Mete; Schneider, Christian; Höfling, Sven; Kamp, Martin; Lu, Chao-Yang; Pan, Jian-Wei

    2013-01-01

    Single photon sources based on semiconductor quantum dots offer distinct advantages for quantum information, including a scalable solid-state platform, ultrabrightness, and interconnectivity with matter qubits. A key prerequisite for their use in optical quantum computing and solid-state networks is a high level of efficiency and indistinguishability. Pulsed resonance fluorescence (RF) has been anticipated as the optimum condition for the deterministic generation of high-quality photons with vanishing effects of dephasing. Here, we generate pulsed RF single photons on demand from a single, microcavity-embedded quantum dot under s-shell excitation with 3-ps laser pulses. The pi-pulse excited RF photons have less than 0.3% background contributions and a vanishing two-photon emission probability. Non-postselective Hong-Ou-Mandel interference between two successively emitted photons is observed with a visibility of 0.97(2), comparable to trapped atoms and ions. Two single photons are further used to implement a h...

  2. Ultrabright single-photon source on diamond with electrical pumping at room and high temperatures

    Science.gov (United States)

    Fedyanin, D. Yu; Agio, M.

    2016-07-01

    The recently demonstrated electroluminescence of color centers in diamond makes them one of the best candidates for room temperature single-photon sources. However, the reported emission rates are far off what can be achieved by state-of-the-art electrically driven epitaxial quantum dots. Since the electroluminescence mechanism has not yet been elucidated, it is not clear to what extent the emission rate can be increased. Here we develop a theoretical framework to study single-photon emission from color centers in diamond under electrical pumping. The proposed model comprises electron and hole trapping and releasing, transitions between the ground and excited states of the color center as well as structural transformations of the center due to carrier trapping. It provides the possibility to predict both the photon emission rate and the wavelength of emitted photons. Self-consistent numerical simulations of the single-photon emitting diode based on the proposed model show that the photon emission rate can be as high as 100 kcounts s-1 at standard conditions. In contrast to most optoelectronic devices, the emission rate steadily increases with the device temperature achieving of more than 100 Mcount s-1 at 500 K, which is highly advantageous for practical applications. These results demonstrate the potential of color centers in diamond as electrically driven non-classical light emitters and provide a foundation for the design and development of single-photon sources for optical quantum computation and quantum communication networks operating at room and higher temperatures.

  3. 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

  4. 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

  5. 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

  6. Electrically Driven InAs Quantum-Dot Single-Photon Sources

    Institute of Scientific and Technical Information of China (English)

    XIONG Yong-Hua; NIU Zhi-Chuan; DOU Xiu-Ming; SUN Bao-Quan; HUANG She-Song; NI Hai-Qiao; DU Yun; XIA Jian-Bai

    2009-01-01

    Electrically driven single photon source based on single InAs quantum dot (QDs) is demonstrated. The device contains InAs QDs within a planar cavity formed between a bottom AIGaAs/GaAs distributed Bragg reflector (DBR) and a surface GaAs-air interface. The device is characterized by Ⅰ-Ⅴ curve and electroluminescence, and a single sharp exciton emission line at 966 nm is observed. Hanbury Brown and Twiss (HBT) correlation measurements demonstrate single photon emission with suppression of multiphoton emission to below 45% at 80 K

  7. Plasmonic-enhanced two-photon fluorescence with single gold nanoshell

    Science.gov (United States)

    Zhang, TianYue; Lu, GuoWei; Shen, HongMing; Perriat, P.; Martini, M.; Tillement, O.; Gong, QiHuang

    2014-06-01

    Single gold nanoshell with mutilpolar plasmon resonances is proposed to enhance two-photon fluorescence efficiently. The single emitter single nanoshell configuration is studied systematically by employing the finite-difference time-domain method. The emitter located inside or outside the nanoshell at various positions leads to a significantly different enhancement effect. The fluorescent emitter placed outside the nanoshell can achieve large fluorescence intensity given that both the position and orientation of the emission dipole are optimally controlled. In contrast, for the case of the emitter placed inside the nanoshell, it can experience substantial two-photon fluorescence enhancement without strict requirements upon the position and dipole orientations. Metallic nanoshell encapsulating many fluorescent emitters should be a promising nanocomposite configuration for bright two-photon fluorescence label. The results provide a comprehensive understanding about the plasmonic-enhanced two-photon fluorescence behaviors, and the nanocomposite configuration has great potential for optical detecting, imaging and sensing in biological applications.

  8. 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

    wavelength of single quantum dots is temperature tuned across the band edge of a photonic crystal waveguide and the spontaneous emission rate is recorded. Decay rates up to 5.7 ns−1, corresponding to a Purcell factor of 5.2, are measured and β-factors up to 85% are extracted. These results prove......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...... the potential of photonic crystal waveguides in the realization of on-chip single-photon sources....

  9. Correlated Photon Emission from a Single II-VI Quantum Dot

    CERN Document Server

    Couteau, C; Tinjod, F; Gérard, J M; Kheng, K; Mariette, H; Gaj, J A; Romestain, R; Poizat, J P

    2004-01-01

    We report correlation and cross-correlation measurements of photons emitted under continuous wave excitation by a single II-VI quantum dot (QD) grown by molecular-beam epitaxy. A standard technique of microphotoluminescence combined with an ultrafast photon correlation set-up allowed us to see an antibunching effect on photons emitted by excitons recombining in a single CdTe/ZnTe QD, as well as cross-correlation within the biexciton ($X_{2}$)-exciton ($X$) radiative cascade from the same dot. Fast microchannel plate photomultipliers and a time-correlated single photon module gave us an overall temporal resolution of 140 ps better than the typical exciton lifetime in II-VI QDs of about 250ps.

  10. Enhancing the Linear Dynamic Range in Multi-Channel Single Photon Detector beyond 7OD

    Science.gov (United States)

    Gudkov, Dmytro; Gudkov, George; Gorbovitski, Boris; Gorfinkel, Vera

    2015-01-01

    We present design, implementation, and characterization of a single photon detector based on 32-channel PMT sensor [model H7260-20, Hamamatsu]. The developed high speed electronics enables the photon counting with linear dynamic range (LDR) up to 108count/s per detector's channel. The experimental characterization and Monte-Carlo simulations showed that in the single photon counting mode the LDR of the PMT sensor is limited by (i) “photon” pulse width (current pulse) of 900ps and (ii) substantial decrease of amplitudes of current pulses for count rates exceeding 108 count/s. The multi-channel architecture of the detector and the developed firm/software allow further expansion of the dynamic range of the device by 32-fold by using appropriate beam shaping. The developed single photon counting detector was tested for the detection of fluorescence labeled microbeads in capillary flow. PMID:27087788

  11. Single-Photon Avalanche Diodes (SPAD) in CMOS 0.35 μm technology

    Science.gov (United States)

    Pellion, D.; Jradi, K.; Brochard, N.; Prêle, D.; Ginhac, D.

    2015-07-01

    Some decades ago single photon detection used to be the terrain of photomultiplier tube (PMT), thanks to its characteristics of sensitivity and speed. However, PMT has several disadvantages such as low quantum efficiency, overall dimensions, and cost, making them unsuitable for compact design of integrated systems. So, the past decade has seen a dramatic increase in interest in new integrated single-photon detectors called Single-Photon Avalanche Diodes (SPAD) or Geiger-mode APD. SPAD are working in avalanche mode above the breakdown level. When an incident photon is captured, a very fast avalanche is triggered, generating an easily detectable current pulse. This paper discusses SPAD detectors fabricated in a standard CMOS technology featuring both single-photon sensitivity, and excellent timing resolution, while guaranteeing a high integration. In this work, we investigate the design of SPAD detectors using the AMS 0.35 μm CMOS Opto technology. Indeed, such standard CMOS technology allows producing large surface (few mm2) of single photon sensitive detectors. Moreover, SPAD in CMOS technologies could be associated to electronic readout such as active quenching, digital to analog converter, memories and any specific processing required to build efficient calorimeters1

  12. Nonlocality of a single photon: paths to an EPR-steering experiment

    CERN Document Server

    Jones, S J

    2011-01-01

    A single photon incident on a beam splitter produces an entangled field state, and in principle could be used to violate a Bell-inequality, but such an experiment (without post-selection) is beyond the reach of current experiments. Here we consider the somewhat simpler task of demonstrating EPR-steering with a single photon (also without post-selection). That is, of demonstrating that Alice's choice of measurement on her "half" of a single photon can affect the other "half" of the photon in Bob's lab, in a sense rigorously defined by us and Doherty [Phys. Rev. Lett. 98, 140402 (2007)]. Previous work by Lvovsky and co-workers [Phys. Rev. Lett. 92, 047903 (2004)] has addressed this phenomenon (which they called "remote preparation") experimentally using homodyne measurements on a single photon. Here we show that, unfortunately, their experimental parameters do not meet the bounds necessary for a rigorous demonstration of EPR-steering with a single photon. However, we also show that modest improvements in the ex...

  13. Single photon detection in a waveguide-coupled Ge-on-Si lateral avalanche photodiode.

    Science.gov (United States)

    Martinez, Nicholas J D; Gehl, Michael; Derose, Christopher T; Starbuck, Andrew L; Pomerene, Andrew T; Lentine, Anthony L; Trotter, Douglas C; Davids, Paul S

    2017-07-10

    We examine gated-Geiger mode operation of an integrated waveguide-coupled Ge-on-Si lateral avalanche photodiode (APD) and demonstrate single photon detection at low dark count for this mode of operation. Our integrated waveguide-coupled APD is fabricated using a selective epitaxial Ge-on-Si growth process resulting in a separate absorption and charge multiplication (SACM) design compatible with our silicon photonics platform. Single photon detection efficiency and dark count rate is measured as a function of temperature in order to understand and optimize performance characteristics in this device. We report single photon detection of 5.27% at 1310 nm and a dark count rate of 534 kHz at 80 K for a Ge-on-Si single photon avalanche diode. Dark count rate is the lowest for a Ge-on-Si single photon detector in this range of temperatures while maintaining competitive detection efficiency. A jitter of 105 ps was measured for this device.

  14. Wigner spectrum and coherent feedback control of continuous-mode single-photon Fock states

    Science.gov (United States)

    Dong, Zhiyuan; Cui, Lei; Zhang, Guofeng; Fu, Hongchen

    2016-10-01

    Single photons are very useful resources in quantum information science. In real applications it is often required that the photons have a well-defined spectral (or equivalently temporal) modal structure. For example, a rising exponential pulse is able to fully excite a two-level atom while a Gaussian pulse cannot. This motivates the study of continuous-mode single-photon Fock states. Such states are characterized by a spectral (or temporal) pulse shape. In this paper we investigate the statistical property of continuous-mode single-photon Fock states. Instead of the commonly used normal ordering (Wick order), the tool we proposed is the Wigner spectrum. The Wigner spectrum has two advantages: (1) it allows to study continuous-mode single-photon Fock states in the time domain and frequency domain simultaneously; (2) because it can deal with the Dirac delta function directly, it has the potential to provide more information than the normal ordering where the Dirac delta function is always discarded. We also show how various control methods in particular coherent feedback control can be used to manipulate the pulse shapes of continuous-mode single-photon Fock states.

  15. Photonic mode density effects on single-molecule fluorescence blinking

    CERN Document Server

    Stefani, F D; Bocchio, N; Gaul, F; Pomozzi, A; Kreiter, M

    2006-01-01

    We investigated the influence of the photonic mode density (PMD) on the triplet dynamics of individual chromophores on a dielectric interface by comparing their response in the presence and absence of a nearby gold film. Lifetimes of the excited singlet state were evaluated in ordet to measure directly the PMD at the molecules position. Triplet state lifetimes were simultaneously determined by statistical analysis of the detection time of the fluorescence photons. The observed singlet decay rates are in agreement with the predicted PMD for molecules with different orientations. The triplet decay rate is modified in a fashion correlated to the singlet decay rate. These results show that PMD engineering can lead to an important suppression of the fluorescence, introducing a novel aspect of the physical mechanism to enhance fluorescence intensity in PMD-enhancing systems such as plasmonic devices.

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

    Science.gov (United States)

    2012-07-01

    above both CHAPTER 4. NOISE PROCESSES IN QFC DEVICES 41 5 5.5 6 6.5 7 7.5 0 2 4 6 8 Domain Width (µm) P ro ba bi lit y (% ) Figure 4.5: Histogram of...photons of different color. Optics Communications, 283(5):747–752, March 2010. BIBLIOGRAPHY 140 [20] Paul G. Kwiat, Klaus Mattle, Harald Weinfurter

  17. 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.

  18. In-depth study of single photon time resolution for the Philips digital silicon photomultiplier

    Science.gov (United States)

    Liu, Z.; Gundacker, S.; Pizzichemi, M.; Ghezzi, A.; Auffray, E.; Lecoq, P.; Paganoni, M.

    2016-06-01

    The digital silicon photomultiplier (SiPM) has been commercialised by Philips as an innovative technology compared to analog silicon photomultiplier devices. The Philips digital SiPM, has a pair of time to digital converters (TDCs) connected to 12800 single photon avalanche diodes (SPADs). Detailed measurements were performed to understand the low photon time response of the Philips digital SiPM. The single photon time resolution (SPTR) of every single SPAD in a pixel consisting of 3200 SPADs was measured and an average value of 85 ps full width at half maximum (FWHM) was observed. Each SPAD sends the signal to the TDC with different signal propagation time, resulting in a so called trigger network skew. This distribution of the trigger network skew for a pixel (3200 SPADs) has been measured and a variation of 50 ps FWHM was extracted. The SPTR of the whole pixel is the combination of SPAD jitter, trigger network skew, and the SPAD non-uniformity. The SPTR of a complete pixel was 103 ps FWHM at 3.3 V above breakdown voltage. Further, the effect of the crosstalk at a low photon level has been studied, with the two photon time resolution degrading if the events are a combination of detected (true) photons and crosstalk events. Finally, the time response to multiple photons was investigated.

  19. Single-photon experiments with liquid crystals for quantum science and quantum engineering applications

    Science.gov (United States)

    Lukishova, Svetlana G.; Liapis, Andreas C.; Bissell, Luke J.; Gehring, George M.; Winkler, Justin M.; Boyd, Robert W.

    2015-03-01

    We present here our results on using liquid crystals in experiments with nonclassical light sources: (1) single-photon sources exhibiting antibunching (separation of all photons in time), which are key components for secure quantum communication systems, and (2) entangled photon source with photons exhibiting quantum interference in a Hong-Ou- Mandel interferometer. In the first part, cholesteric liquid crystal hosts were used to create definite circular polarization of antibunched photons emitted by nanocrystal quantum dots. If the photon has unknown polarization, filtering it through a polarizer to produce the desired polarization for quantum key distribution with bits based on polarization states of photons will reduce by half the efficiency of a quantum cryptography system. In the first part, we also provide our results on observation of a circular polarized microcavity resonance in nanocrystal quantum dot fluorescence in a 1-D chiral photonic bandgap cholesteric liquid crystal microcavity. In the second part of this paper with indistinguishable, time-entangled photons, we demonstrate our experimental results on simulating quantum-mechanical barrier tunnelling phenomena. A Hong-Ou-Mandel dip (quantum interference effect) is shifted when a phase change was introduced on the way of one of entangled photons in pair (one arm of the interferometer) by inserting in this arm an electrically controlled planar-aligned nematic liquid crystal layer between two prisms in the conditions close to a frustrated total internal reflection. By applying different AC-voltages to the planar-aligned nematic layer and changing its refractive index, we can obtain various conditions for incident photon propagation - from total reflection to total transmission. Measuring changes of tunnelling times of photon through this structure with femtosecond resolution permitted us to answer some unresolved questions in quantum-mechanical barrier tunnelling phenomena.

  20. 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.)

  1. 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.

  2. Three-dimensional single gyroid photonic crystals with a mid-infrared bandgap

    CERN Document Server

    Peng, Siying; Chen, Valerian H; Khabiboulline, Emil T; Braun, Paul; Atwater, Harry A

    2016-01-01

    A gyroid structure is a distinct morphology that is triply periodic and consists of minimal isosurfaces containing no straight lines. We have designed and synthesized amorphous silicon (a-Si) mid-infrared gyroid photonic crystals that exhibit a complete bandgap in infrared spectroscopy measurements. Photonic crystals were synthesized by deposition of a-Si/Al2O3 coatings onto a sacrificial polymer scaffold defined by two-photon lithography. We observed a 100% reflectance at 7.5 \\mum for single gyroids with a unit cell size of 4.5 \\mum, in agreement with the photonic bandgap position predicted from full-wave electromagnetic simulations, whereas the observed reflection peak shifted to 8 um for a 5.5 \\mum unit cell size. This approach represents a simulation-fabrication-characterization platform to realize three-dimensional gyroid photonic crystals with well-defined dimensions in real space and tailored properties in momentum space.

  3. 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.

  4. Electro-mechanical engineering of non-classical photon emissions from single quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Hoefer, Bianca; Zallo, Eugenio; Zhang, Jiaxiang; Ding, Fei; Schmidt, Oliver G. [Institute for Integrative Nanosciences, IFW-Dresden, Helmholtzstrasse 20, D-01069 Dresden (Germany); Trotta, Rinaldo; Rastelli, Armando [Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz, Altenbergerstrasse 69, A-4040 Linz (Austria)

    2014-07-01

    Indistinguishable photons and entangled photon pairs are the key elements for quantum information applications, for example, building a quantum repeater. Self-assembled semiconductor quantum dots (QDs) are promising candidates for the creation of such non-classical photon emissions, and offer the possibility to be integrated into solid state devices. However, due to the random nature of the self-assembled growth process, post-growth treatments are required to engineer the exciton state in the QDs (e.g. energies, exciton lifetimes, and fine structure splittings). In this work, we study the electro-mechanical engineering of the exciton lifetime, emission energy in the QDs, with the aim to produce single photons with higher indistinguishability. Also we present a recent experimental study on the statistical properties of fine structure splittings in the QD ensemble, in order to gain a deeper understanding of how to generate entangled photon pairs using semiconductor QDs.

  5. Photon Energy Deposition in Strong-Field Single Ionization of Multielectron Molecules.

    Science.gov (United States)

    Zhang, Wenbin; Li, Zhichao; Lu, Peifen; Gong, Xiaochun; Song, Qiying; Ji, Qinying; Lin, Kang; Ma, Junyang; He, Feng; Zeng, Heping; Wu, Jian

    2016-09-01

    Molecules exposed to strong laser fields may coherently absorb multiple photons and deposit the energy into electrons and nuclei, triggering the succeeding dynamics as the primary stage of the light-molecule interaction. We experimentally explore the electron-nuclear sharing of the absorbed photon energy in above-threshold multiphoton single ionization of multielectron molecules. Using CO as a prototype, vibrational and orbital resolved electron-nuclear sharing of the photon energy is observed. Different from the simplest one- or two-electron systems, the participation of the multiple orbitals and the coupling of various electronic states in the strong-field ionization and dissociation processes alter the photon energy deposition dynamics of the multielectron molecule. The population of numerous vibrational states of the molecular cation as the energy reservoir in the ionization process plays an important role in photon energy sharing between the emitted electron and the nuclear fragments.

  6. Near-infrared single-photon spectroscopy of a whispering gallery mode resonator using energy-resolving transition edge sensors

    CERN Document Server

    Förtsch, Michael; Stevens, Martin J; Strekalov, Dmitry; Schunk, Gerhard; Fürst, Josef U; Vogl, Ulrich; Sedlmeir, Florian; Schwefel, Harald G L; Leuchs, Gerd; Nam, Sae Woo; Marquardt, Christoph

    2014-01-01

    We demonstrate a method to perform spectroscopy of near-infrared single photons without the need of dispersive elements. This method is based on a photon energy resolving transition edge sensor and is applied for the characterization of widely wavelength tunable narrow-band single photons emitted from a crystalline whispering gallery mode resonator. We measure the emission wavelength of the generated signal and idler photons with an uncertainty of up to 2 nm.

  7. Single-Photon Emission of a Hydrogenlike Atom

    Science.gov (United States)

    Skobelev, V. V.

    2016-11-01

    Implementing a previously obtained, original solution of the Dirac equation for an electron in the field of a nucleus ( Ze) expressed in terms of the wave function of the corresponding Schrödinger equation and its derivatives in spherical coordinates and the spin projection operator Σ3 associated with the eigenfunction, taking into account in each component of the spinor the leading term of the expansion in the small parameter ( Zα), α = e 2 / ħc ≈ 1 / 137, the partial probabilities W of emission of a photon ( Zα)* → ( Zα) + γ have been calculated. Here two orthogonal states of the linear polarization of the photon, and also the spin states of the electron, which previously had not been taken into consideration, have been taken into account in the transverse gauge. It turns out that the probabilities W of emission of a photon per unit time for any allowed transitions are proportional to (Zα)4, as was previously accepted, and the selection rules for the quantum number m have the usual form ∆ m = 0,±1. It was found that a spin flip does not take place during emission. In contrast to the customary situation with the selection rules for the quantum number l being of the form ∆ l = ±1, for ∆ m = ±1 there also exist integrals over dcosθ which are not equal to zero for undetermined odd values of ∆ l. In this, and also in a fundamentally different dependence of the amplitude on the quantum numbers consist the differences from the traditional approach to the problem. Necessary conditions are formulated, under the fulfillment of which the selection rules for l are not changed, having values ∆ l = ±1 for arbitrary ∆ m, but it was not possible, however, to give a complete proof of these rules.

  8. 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

  9. Single Photon Counting Detectors for Low Light Level Imaging Applications

    Science.gov (United States)

    Kolb, Kimberly

    2015-10-01

    This dissertation presents the current state-of-the-art of semiconductor-based photon counting detector technologies. HgCdTe linear-mode avalanche photodiodes (LM-APDs), silicon Geiger-mode avalanche photodiodes (GM-APDs), and electron-multiplying CCDs (EMCCDs) are compared via their present and future performance in various astronomy applications. LM-APDs are studied in theory, based on work done at the University of Hawaii. EMCCDs are studied in theory and experimentally, with a device at NASA's Jet Propulsion Lab. The emphasis of the research is on GM-APD imaging arrays, developed at MIT Lincoln Laboratory and tested at the RIT Center for Detectors. The GM-APD research includes a theoretical analysis of SNR and various performance metrics, including dark count rate, afterpulsing, photon detection efficiency, and intrapixel sensitivity. The effects of radiation damage on the GM-APD were also characterized by introducing a cumulative dose of 50 krad(Si) via 60 MeV protons. Extensive development of Monte Carlo simulations and practical observation simulations was completed, including simulated astronomical imaging and adaptive optics wavefront sensing. Based on theoretical models and experimental testing, both the current state-of-the-art performance and projected future performance of each detector are compared for various applications. LM-APD performance is currently not competitive with other photon counting technologies, and are left out of the application-based comparisons. In the current state-of-the-art, EMCCDs in photon counting mode out-perform GM-APDs for long exposure scenarios, though GM-APDs are better for short exposure scenarios (fast readout) due to clock-induced-charge (CIC) in EMCCDs. In the long term, small improvements in GM-APD dark current will make them superior in both long and short exposure scenarios for extremely low flux. The efficiency of GM-APDs will likely always be less than EMCCDs, however, which is particularly disadvantageous for

  10. Highly efficient generation of single-mode photon pairs using a crystalline whispering gallery mode resonator

    CERN Document Server

    Förtsch, Michael; Fürst, Josef U; Strekalov, Dmitry; Gerrits, Thomas; Stevens, Martin J; Sedlmeir, Florian; Schwefel, Harald G L; Nam, Sae Woo; Leuchs, Gerd; Marquardt, Christoph

    2014-01-01

    We report a highly efficient source of narrow-band photon pairs based on parametric down-conversion in a crystalline whispering gallery mode resonator. Remarkably, each photon of a pair is strictly emitted into a single spatial and temporal mode, as witnessed by Glaubers autocorrelation function. We explore the phase-matching conditions in spherical geometries, and determine the requirements of the single-mode operation. Understanding these conditions has allowed us to experimentally demonstrate a single-mode pair-detection rate of $0.97 \\cdot 10^6$ pairs/s per mW pump power per 20 MHz bandwidth without the need of additional filter cavities.

  11. Exploiting Rydberg Atom Surface Phonon Polariton Coupling for Single Photon Subtraction

    CERN Document Server

    Kübler, H; Sedlacek, J; Zabawa, P; Shaffer, J P

    2013-01-01

    We investigate a hybrid quantum system that consists of a superatom coupled to a surface phonon-polariton. We apply this hybrid quantum system to subtract individual photons from a beam of light. Rydberg atom blockade is used to attain absorption of a single photon by an atomic microtrap. Surface phonon-polariton coupling to the superatom then triggers the transfer of the excitation to a storage state, a single Rydberg atom. The approach utilizes the interaction between a superatom and a Markovian bath that acts as a controlled decoherence mechanism to irreversibly project the superatom state into a single Rydberg atom state that can be read out.

  12. Increasing the photon collection rate from a single NV center with a silver mirror

    DEFF Research Database (Denmark)

    Israelsen, Niels Møller; Kumar, Shailesh; Tawfieq, Mahmoud

    2014-01-01

    In the pursuit of realizing quantum optical networks, a large variety of different approaches have been studied to achieve a single photon source on-demand. The common goal for these approaches is to harvest all the emission from a quantum emitter into a single spatial optical mode while...... maintaining a high signal-to-noise ratio. In this work, we use a single nitrogen vacancy center in diamond as a quantum emitter operating at ambient conditions and we demonstrate an increased photon count rate up to a factor of 1.76 by placing a silver mirror fabricated on the end facet of an optical fiber...

  13. Single-photon transport through a waveguide coupling to a quadratic optomechanical system

    Science.gov (United States)

    Qiao, Lei

    2017-07-01

    We study the coherent transport of a single photon, which propagates in a one-dimensional waveguide and is scattered by a quadratic optomechanical system. Our approach, which is based on the Lippmann-Schwinger equation, gives an analytical solution to describe the single-photon transmission and reflection properties. We analyze the transport spectra and find they are not only related to the optomechanical system's energy-level structure, but also dependent on the optomechanical system's inherent parameters. For the existence of atomic degrees of freedom, we get a Rabi-splitting-like or an electromagnetically induced transparency (EIT)-like spectrum, depending on the atom-cavity coupling strength. Here, we focus on the single-photon strong-coupling regime so that single-quantum effects could be seen.

  14. Superconducting nanowire single-photon detectors (SNSPDs) on SOI for near-infrared range

    Energy Technology Data Exchange (ETDEWEB)

    Trojan, Philipp; Il' in, Konstantin; Henrich, Dagmar; Hofherr, Matthias; Doerner, Steffen; Siegel, Michael [Institut fuer Mikro- und Nanoelektronische Systeme (IMS), Karlsruher Institut fuer Technologie (KIT) (Germany); Semenov, Alexey [Institut fuer Planetenforschung, DLR, Berlin-Adlershof (Germany); Huebers, Heinz-Wilhelm [Institut fuer Planetenforschung, DLR, Berlin-Adlershof (Germany); Institut fuer Optik und Atomare Physik, Technische Universitaet Berlin (Germany)

    2013-07-01

    Superconducting nanowire single-photon detectors are promising devices for photon detectors with high count rates, low dark count rates and low dead times. At wavelengths beyond the visible range, the detection efficiency of today's SNSPDs drops significantly. Moreover, the low absorption in ultra-thin detector films is a limiting factor over the entire spectral range. Solving this problem requires approaches for an enhancement of the absorption range in feeding the light to the detector element. A possibility to obtain a better absorption is the use of multilayer substrate materials for photonic waveguide structures. We present results on development of superconducting nanowire single-photon detectors made from niobium nitride on silicon-on-insulator (SOI) multilayer substrates. Optical and superconducting properties of SNSPDs on SOI will be discussed and compared with the characteristics of detectors on common substrates.

  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. Nonclassical correlations between single photons and phonons from a mechanical oscillator

    CERN Document Server

    Riedinger, Ralf; Norte, Richard A; Slater, Joshua A; Shang, Juying; Krause, Alexander G; Anant, Vikas; Aspelmeyer, Markus; Gröblacher, S

    2015-01-01

    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 for fundamental tests of quantum physics as well as for realizations of quantum networks. Here we report nonclassical 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 readout of correlated photon-phonon pairs. The observed violation of a Cauchy-Schwarz inequality is clear evidence for the nonclassical nature of the generated mechanical state. Our results show the availability of on-chip solid-state mechanical resonators as light-matter ...

  17. Bright and stable visible-spectrum single photon emitter in silicon carbide

    CERN Document Server

    Lienhard, Benjamin; Mouradian, Sara; Dolde, Florian; Tran, Toan Trong; Aharonovich, Igor; Englund, Dirk R

    2016-01-01

    Single photon sources are of paramount importance in quantum communication, quantum computation, and quantum metrology. In particular, there is great interest to realize scalable solid state platforms that can emit triggered photons on demand to achieve scalable nanophotonic networks. We report on a visible-spectrum single photon emitter in 4H-silicon carbide (SiC). The emitter is photostable at room- and low-temperature enabling photon counts per second (cps) in excess of 2$\\times$10$^6$ from unpatterned, bulk SiC. It exists in two orthogonally polarized states, which have parallel absorption and emission dipole orientations. Low temperature measurements reveal a narrow zero phonon line (linewidth $30~$% of the total photoluminescence spectrum.

  18. Spectrally resolved single-photon imaging with hybrid superconducting - nanophotonic circuits

    CERN Document Server

    Kahl, O; Kovalyuk, V; Vetter, A; Lewes-Malandrakis, G; Nebel, C; Korneev, A; Goltsman, G; Pernice, W

    2016-01-01

    The detection of individual photons is an inherently binary mechanism, revealing either their absence or presence while concealing their spectral information. For multi-color imaging techniques, such as single photon spectroscopy, fluorescence resonance energy transfer microscopy and fluorescence correlation spectroscopy, wavelength discrimination is essential and mandates spectral separation prior to detection. Here, we adopt an approach borrowed from quantum photonic integration to realize a compact and scalable waveguide-integrated single-photon spectrometer capable of parallel detection on multiple wavelength channels, with temporal resolution below 50 ps and dark count rates below 10 Hz. We demonstrate multi-detector devices for telecommunication and visible wavelengths and showcase their performance by imaging silicon vacancy color centers in diamond nanoclusters. The fully integrated hybrid superconducting-nanophotonic circuits enable simultaneous spectroscopy and lifetime mapping for correlative imagi...

  19. 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

  20. Practical non-orthogonal decoy state quantum key distribution with heralded single photon source

    Institute of Scientific and Technical Information of China (English)

    Mi Jing-Long; Wang Fa-Qiang; Lin Qing-Qun; Liang Rui-Sheng

    2008-01-01

    Recently the performance of the quantum key distribution (QKD) is substantially improved by the decoy state method and the non-orthogonal encoding protocol, separately. In this paper, a practical non-orthogonal decoy state protocol with a heralded single photon source (HSPS) for QKD is presented. The protocol is based on 4 states with different intensities, i.e. one signal state and three decoy states. The signal state is for generating keys; the decoy states arc for detecting the eavesdropping and estimating the fraction of single-photon and two-photon pulses. We have discussed three cases of this protocol, i.e. the general case, the optimal case and the special case. Moreover, the final key rate over transmission distance is simulated. For the low dark count of the HSPS and the utilization of the two-photon pulses, our protocol has a higher key rate and a longer transmission distance than any other decoy state protocol.