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Sample records for internal quantum reflection

  1. Reflections on Friction in Quantum Mechanics

    Directory of Open Access Journals (Sweden)

    Yair Rezek

    2010-08-01

    Full Text Available Distinctly quantum friction effects of three types are surveyed: internalfriction, measurement-induced friction, and quantum-fluctuation-induced friction. We demonstrate that external driving will lead to quantum internal friction, and critique the measurement-based interpretation of friction. We conclude that in general systems will experience internal and external quantum friction over and beyond the classical frictional contributions.

  2. Total Internal Reflections - Dr. Kapolka Explains Frustrated Total Internal Reflection [video

    OpenAIRE

    Naval Postgraduate School Physics

    2015-01-01

    NPS Physics In-class Physics Demonstrations This is a demo about frustrated total internal reflection. This is a general phenomenon that applies to any kind of wave phenomenon including quantum mechanical waves. Dr. Kapolka is physics professor at the Naval Postgraduate school.

  3. Reflections on international medical law.

    Science.gov (United States)

    Wattad, Mohammed S; Hrevtsova, Radmyla Yu

    2011-12-01

    Does international medical law exist, in the first place, as an independent area of study? If so, is it urgently required in an era of comparative studies? Namely, to what extent, if at all, international studies differ from comparative ones? Besides, what are the particular characteristics of such international discipline? Namely, what are the particular features of this field that elaborate on our legal and scientific understanding in sketching possible definition for this notion of "international medical law?" In addition, how does international medical law correlate with health, ethics and health policies in our globalized world? And finally, what are the challenges that might face the international community, once the concept of "international medical law" is acknowledged? This papers aims at establishing the conceptual grounds for these questions, thus calling for the acknowledgment of a new field of study described as "international medical law".

  4. Studies of the Reflection, Refraction and Internal Reflection of Light

    Science.gov (United States)

    Lanchester, P. C.

    2014-01-01

    An inexpensive apparatus and associated experiments are described for studying the basic laws of reflection and refraction of light at an air-glass interface, and multiple internal reflections within a glass block. In order to motivate students and encourage their active participation, a novel technique is described for determining the refractive…

  5. Total internal reflection effect on gyrotropic interface

    Science.gov (United States)

    Glushchenko, Alexander G.; Glushchenko, Eugene P.; Zhukov, Sergey V.

    2018-02-01

    This article considers the physical features of total internal reflection at gyrotropic and isotropic interfaces for two cases: electrical gyrotropy (plasma) and magnetic gyrotropy (ferrite). It is shown that the plasma magnetization may lead to the formation of the total internal reflection effect, which does not occur in isotropic plasma. The threshold values of the magnetic field, which are necessary for the total internal reflection effect, are determined. The total internal reflection effect on a ferrite-dielectric interface for waves emanating from different angles is observed in various frequency ranges and magnetization fields. The study points out the possibility of changing the total internal reflection angle value in large limits due to a change in the external magnetic field magnitude. The calculation results of the total internal reflection angle dependence on the external magnetic field magnitude are presented. The formulas are elaborated for calculating the total internal reflection angles of different interfaces for gyrotropic and isotropic media. The generalized formulas are defined for calculating the Doppler effect in the gyrotropic media. The study demonstrates how the velocity of the media interface affects the limiting angle of total internal refection.

  6. Andreev reflections and the quantum physics of black holes

    Science.gov (United States)

    Manikandan, Sreenath K.; Jordan, Andrew N.

    2017-12-01

    We establish an analogy between superconductor-metal interfaces and the quantum physics of a black hole, using the proximity effect. We show that the metal-superconductor interface can be thought of as an event horizon and Andreev reflection from the interface is analogous to the Hawking radiation in black holes. We describe quantum information transfer in Andreev reflection with a final state projection model similar to the Horowitz-Maldacena model for black hole evaporation. We also propose the Andreev reflection analogue of Hayden and Preskill's description of a black hole final state, where the black hole is described as an information mirror. The analogy between crossed Andreev reflections and Einstein-Rosen bridges is discussed: our proposal gives a precise mechanism for the apparent loss of quantum information in a black hole by the process of nonlocal Andreev reflection, transferring the quantum information through a wormhole and into another universe. Given these established connections, we conjecture that the final quantum state of a black hole is exactly the same as the ground state wave function of the superconductor/superfluid in the Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity; in particular, the infalling matter and the infalling Hawking quanta, described in the Horowitz-Maldacena model, forms a Cooper pairlike singlet state inside the black hole. A black hole evaporating and shrinking in size can be thought of as the analogue of Andreev reflection by a hole where the superconductor loses a Cooper pair. Our model does not suffer from the black hole information problem since Andreev reflection is unitary. We also relate the thermodynamic properties of a black hole to that of a superconductor, and propose an experiment which can demonstrate the negative specific heat feature of black holes in a growing/evaporating condensate.

  7. Total internal reflection tomography of small objects

    International Nuclear Information System (INIS)

    Chen Xudong

    2008-01-01

    The multiple signal classification (MUSIC) imaging method is applied to determine the locations of a collection of small anisotropic spherical scatterers in the framework of the total internal reflection tomography. Multiple scattering between scatterers is considered and the inverse scattering problem is nonlinear, which, however, is solved by the proposed fast analytical approach where no associated forward problem is iteratively evaluated. The paper also discusses the role of the polarization of incidence waves, the incidence angle, the separation of scatterers from the surface of the substrate, and the level of noise on the resolution of imaging.

  8. Quantum coherence in the reflection of above barrier wavepackets.

    Science.gov (United States)

    Petersen, Jakob; Pollak, Eli

    2018-02-21

    The quantum phenomenon of above barrier reflection is investigated from a time-dependent perspective using Gaussian wavepackets. The transition path time distribution, which in principle is experimentally measurable, is used to study the mean flight times ⟨t⟩ R and ⟨t⟩ T associated with the reflection and the transmission over the barrier paying special attention to their dependence on the width of the barrier. Both flight times, and their difference Δt, exhibit two distinct regimes depending on the ratio of the spatial width of the incident wavepacket and the length of the barrier. When the ratio is larger than unity, the reflection and transmission dynamics are coherent and dominated by the resonances above the barrier. The flight times ⟨t⟩ R/T and the flight time difference Δt oscillate as a function of the barrier width (almost in phase with the transmission probability). These oscillations reflect a momentum filtering effect related to the coherent superposition of the reflected and transmitted waves. For a ratio less than unity, the barrier reflection and transmission dynamics are incoherent and the oscillations are absent. The barrier width which separates the coherent and incoherent regimes is identified analytically. The oscillatory structure of the time difference Δt as a function of the barrier width in the coherent regime is absent when considered in terms of the Wigner phase time delays for reflection and transmission. We conclude that the Wigner phase time does not correctly describe the temporal properties of above barrier reflection. We also find that the structure of the reflected and transmitted wavepackets depends on the coherence of the process. In the coherent regime, the wavepackets can have an overlapping peak structure, but the peaks are not fully resolved. In the incoherent regime, the wavepackets split in time into distinct separated Gaussian like waves, each one reflecting the number of times the wavepacket crosses the

  9. Quantum coherence in the reflection of above barrier wavepackets

    Science.gov (United States)

    Petersen, Jakob; Pollak, Eli

    2018-02-01

    The quantum phenomenon of above barrier reflection is investigated from a time-dependent perspective using Gaussian wavepackets. The transition path time distribution, which in principle is experimentally measurable, is used to study the mean flight times ⟨t⟩R and ⟨t⟩T associated with the reflection and the transmission over the barrier paying special attention to their dependence on the width of the barrier. Both flight times, and their difference Δt, exhibit two distinct regimes depending on the ratio of the spatial width of the incident wavepacket and the length of the barrier. When the ratio is larger than unity, the reflection and transmission dynamics are coherent and dominated by the resonances above the barrier. The flight times ⟨t⟩R/T and the flight time difference Δt oscillate as a function of the barrier width (almost in phase with the transmission probability). These oscillations reflect a momentum filtering effect related to the coherent superposition of the reflected and transmitted waves. For a ratio less than unity, the barrier reflection and transmission dynamics are incoherent and the oscillations are absent. The barrier width which separates the coherent and incoherent regimes is identified analytically. The oscillatory structure of the time difference Δt as a function of the barrier width in the coherent regime is absent when considered in terms of the Wigner phase time delays for reflection and transmission. We conclude that the Wigner phase time does not correctly describe the temporal properties of above barrier reflection. We also find that the structure of the reflected and transmitted wavepackets depends on the coherence of the process. In the coherent regime, the wavepackets can have an overlapping peak structure, but the peaks are not fully resolved. In the incoherent regime, the wavepackets split in time into distinct separated Gaussian like waves, each one reflecting the number of times the wavepacket crosses the barrier

  10. International Conference on Coherence and Quantum Optics

    CERN Document Server

    RECENT DEVELOPMENTS IN QUANTUM OPTICS

    1993-01-01

    This volume is composed of papers (invited and contributed) presented at the International Conference on Coherence and Quantum Optics held at the University of Hyderabad January 5-January 10, 1991. It has been organized by Professor Girish Agarwal and his colleagues at the School of Physics, University of Hyderabad, Hyder­ abad, India under partial support from the Department of Science and Technology, Government of India, International Center for Theoretical Physics, Trieste, Italy and the National Science Foundation, USA. Without the untiring efforts of Prof. Girish Agarwal and the members of his quantum office group, the Conference and the present volume would not have been possible. Some extraordinary circumstances resulted in a delay of the publication of the present volume. Our sincere apologies to all the authors. We deeply regret the inconvenience caused due to the delay. A debt of gratitude is due to Ms. Kim Bella for the excellent typing job of the different versions and the final version of the ma...

  11. Study on Quantum Efficiency Stability of Reflection-Mode GaN Negative Electronic Affinity Photocathode

    OpenAIRE

    Wei Liu; Jiangtao Fu; Guoqiang Zheng

    2014-01-01

    The aim of this study is to analyze the decaying and recovering mechanism of the quantum efficiency for reflection-mode GaN NEA photocathode. One kind of reflection-mode GaN NEA photocathode is designed and grown in the laboratory. The quantum efficiency curves are obtained immediately and six hours later after the sample is fully activated, the quantum efficiency data at different wavelengths are acquired according to the two different quantum efficiency curves, Through the analysis of exper...

  12. PREFACE: International Conference on Quantum Optics and Quantum Information (icQoQi) 2013

    Science.gov (United States)

    2014-11-01

    Quantum Information can be understood as being naturally derived from a new understanding of information theory when quantum systems become information carriers and quantum effects become non negligible. Experiments and the realization of various interesting phenomena in quantum information within the established field of quantum optics have been reported, which has provided a very convenient framework for the former. Together, quantum optics and quantum information are among the most exciting areas of interdisciplinary research in modern day science which cover a broad spectrum of topics, from the foundations of quantum mechanics and quantum information science to the introduction of new types of quantum technologies and metrology. The International Conference on Quantum Optics and Quantum Information (icQoQi) 2013 was organized by the Faculty of Science, International Islamic University Malaysia with the objective of bringing together leading academic scientists, researchers and scholars in the domain of interest from around the world to share their experiences and research results about all aspects of quantum optics and quantum information. While the event was organized on a somewhat modest scale, it was in fact a rather fruitful meeting for established researchers and students as well, especially for the local scene where the field is relatively new. We would therefore, like to thank the organizing committee, our advisors and all parties for having made this event successful and last but not least would extend our sincerest gratitude to IOP for publishing these selected papers from icQoQi2013 in Journal of Physics: Conference Series.

  13. Forensic applications of microscopical infrared internal reflection spectroscopy

    Science.gov (United States)

    Tungol, Mary W.; Bartick, Edward G.; Reffner, John A.

    1994-01-01

    Applications of microscopical infrared internal reflection spectroscopy in forensic science are discussed. Internal reflection spectra of single fibers, hairs, paint chips, vehicle rubber bumpers, photocopy toners, carbon copies, writing ink on paper, lipstick on tissue, black electrical tape, and other types of forensic evidence have been obtained. The technique is convenient, non-destructive, and may permit smeared materials to be analyzed in situ.

  14. Quantum Fest 2016 International Conference on Quantum Phenomena, Quantum Control and Quantum Optics

    International Nuclear Information System (INIS)

    2017-01-01

    The Quantum Fest is a periodic annual festival on Quantum Phenomena, Quantum Control and Geometry of Quantum States, organized by the Center for Research and Advanced Studies (Cinvestav by its acronym in Spanish) and Unidad Profesional Interdisciplinaria en Ingeniería y Tecnologías Avanzadas del Instituto Politécnico Nacional (UPIITA-IPN) in México City, Mexico. The aim of this meeting is to bring together students and researchers which are engaged in the subjects of the festival, from both theoretical and experimental approaches, in order to get lively discussions and to enable a closer contact between them.The Quantum Fest was celebrated for the first time in the Physics Department of Cinvestav (2010), since then it has been hosted in Cinvestav, UPIITA-IPN and the Tecnológico de Monterrey, Campus Estado de México (ITESM-CEM).The Quantum Fest 2016 is the seventh edition of the festival, it took place from October 17 to 21 in the Sala de Usos Múltiples, Edificio I of UPIITA-IPN, and was addressed to join the celebration of the first eighty years of the Instituto Politécnico Nacional as well as the first twenty years of the Unidad Profesional Interdisciplinaria en Ingeniería y Tecnologías Avanzadas del Instituto Politécnico Nacional. We would like to thank the willing of the UPIITA-IPN to offer its facilities as the venue of the festival; all its help provided to simplify the logistics and organization of the conference has been welcomed and is acknowledged.The topics addressed at the short courses of the Quantum Fest 2016 were time asymmetric quantum mechanics, quantum resonances, models of quantum field theory in metamaterials, singular potentials and self-adjoint extensions, nonclassical states of light, Hardy functions and Hilbert space operators.The Lecturers of Quantum Fest 2016 were:Manuel Gadella (Valladolid University, Spain)Maribel Loaiza (Department of Mathematics, Cinvestav, Mexico)Luis Miguel Nieto (Valladolid University, Spain)Oscar Rosas

  15. Reflections on Dead Theory in International Relations

    Science.gov (United States)

    Thakur, Vineet

    2016-01-01

    In this short autobiographical essay, I trace my journey in the discipline of International Relations. While entering the discipline, I, along with a host of my classmates, were enamoured by the exciting possibilities of thinking theoretically. Almost a decade later, those promises look bleak. From the perspective of a student in the discipline, I…

  16. International Conference on Laser Physics and Quantum Optics

    CERN Document Server

    Xie, Shengwu; Zhu, Shi-Yao; Scully, Marlan

    2000-01-01

    Since the advent of the laser about 40 years ago, the field of laser physics and quantum optics have evolved into a major discipline. The early studies included the optical coherence theory and the semiclassical and quantum mechanical theories of the laser. More recently many new and interesting effects have been predicted. These include the role of coherent atomic effects in lasing without inversion and electromagnetically induced transparency, atom optics, laser cooling and trapping, teleportation, the single-atom micromaser and its role in quantum measurement theory, to name a few. The International Conference on Laser Physics and Quantum Optics was held in Shanghai from August 25 to August 28, 1999, to discuss these and many other exciting developments in laser physics and quantum optics. The international character of the conference was manifested by the fact that scientists from over 13 countries participated and lectured at the conference. There were four keynote lectures delivered by Nobel laureate Wi...

  17. Reflections about therapeutic internments and his specificity

    Directory of Open Access Journals (Sweden)

    Ángel Estalayo Hernández

    2014-10-01

    Full Text Available There are cases treated in detention centers that present some specificities with respect to other affordable educational strategies from social component. This we refer to the need to address situations in which the same symptom of transgression resulting in an offense that carries a legal measure has other bases that generate and / or maintain, or etiology marking its expression and so much attention. The approach to interventions with children and young people is a seriously disruptive content submitted to numerous debates, discussions and disagreements. In this regard, therapeutic placements would be for those cases in which the intervention on symptom requires a specific and specialized perspective. Beyond clinical approaches, therapeutic placements should from the intervention on self-regulation problems (emotional, behavioral, and cognitive and behavioral expression and as a key defining element. To this we add that we have observed in our practice in recent years an increase in problems related to the field of mental health and / or drug and alcohol consumption on children and young people entering the judicial context. This requires expertise and implement a therapeutic approach in centers for juvenile justice. It is particularly important in these cases performed from the beginning of internment clinical and social diagnostics to guide and design the specific educational and therapeutic intervention required for each particular case, in the interest of optimizing the operation and achieve higher levels of efficiency

  18. Quantum Yield of Reflection Mode Varied Doping GaN Photocathode

    OpenAIRE

    Qiao Jianliang; Li Xiangjiang; Niu Jun; Gao Youtang

    2016-01-01

    Using the NEA photocathode activation and evaluation experiment system, the varied doping GaN photocathode has been activated and evaluated. According to the diffusion and orientation drifting equation, the quantum yield formula of reflection mode varied doping NEA GaN photocathode was gotten. The factors affecting the quantum efficiency of varied doping GaN photocathode were studied. For the varied doping GaN photocathode, the quantum efficiency is mainly decided by the escape probability of...

  19. International Conference on Quantum Science and Applications (ICQSA-2016)

    International Nuclear Information System (INIS)

    Algin, A.; Arik, M.; Gavrilik, A. M.

    2016-01-01

    This special volume of Journal of Physics: Conference Series is dedicated to the proceedings of “International Conference on Quantum Science and Applications (ICQSA-2016)”. The conference was organized by the Centre for Quantum Research and Applications at Eskisehir Osmangazi University, Eskisehir, Turkey. It was held in Eskisehir Osmangazi University Congress and Culture Centre during May 25-27, 2016 http://icqsa2016.ogu.edu.tr. It gathered actively 143 participants from different disciplines in natural and applied sciences coming from 16 different countries from all over the word. It was the first international conference in its content on the scientific research fields of quantum science and applications in Turkey. It also consisted of 12 plenary lectures and 119 contributed oral presentations covering interdisciplinary fields of research. The ICQSA-2016 conference focused on recent modern theoretical and experimental developments of quantum science in multi-disciplinary aspects of areas of mathematics, physics, statistics, chemistry, biology, computer science, electronics, informatics, medicine, education, etc. It served as an interaction platform for students, researchers, public, and private sector delegates for sharing new scientific and technological ideas on quantum applications in science and technology. The topics of the conference were: Quantum theory and quantum computing, quantum information theory and its applications, quantum statistics and its applications, quantum thermodynamics, quantum cryptography, classical and quantum symmetries, quantum calculus in science, engineering, medicine, education, etc., classical and quantum integrable systems, modeling and numerical methods in quantum systems, other modern mathematical methods in science and technology. Each of the submitted papers for this special volume of the proceedings of ICQSA-2016 has been reviewed by external referees. There are 36 accepted papers. Besides, it is worth pointing out

  20. The Reflection of Quantum Aesthetics in Algis Mickūnas Cosmic Philosophy

    Directory of Open Access Journals (Sweden)

    Auridas Gajauskas

    2011-04-01

    Full Text Available Quantum Aesthetics phenomenon was formed in Spain, at the end of the twentieth centure. The paper analyzes this movement in the context of Algis Mickūnas phenomenological cosmic philosophy. Movement initiator is a Spanish novelist Gregorio Morales. The study is divided into two parts: the first part presents aesthetic principles of the quantum, relationship between new aesthetics and theories of quantum mechanics, physics and other sciences. The paper also examines the similarities of quantum aesthetics and New Age movements. The second part presents cosmic - phenomenological reflection of quantum theory of beauty. Mickūnas philosophical position combines theory of "eternal recurrence", "the bodily nature of consciousness", "the cosmic dance", theory of "dynamic fields" and quantum approach to aesthetics and the Universe. Summa Summarum he writes that "the conception of quantum aesthetics is involved in the composition of the rhythmic, cyclical and mood dimensioned and tensed world". 

  1. Bohm's quantum potential as an internal energy

    Energy Technology Data Exchange (ETDEWEB)

    Dennis, Glen, E-mail: gdennis502@gmail.com [TPRU, Birkbeck College, University of London, London, WC1E 7HX (United Kingdom); Gosson, Maurice A. de, E-mail: maurice.de.gosson@univie.ac.at [University of Vienna, Faculty of Mathematics, NuHAG, Oskar-Morgenstern-Platz 1, 1090 Vienna (Austria); Hiley, Basil J., E-mail: b.hiley@bbk.ac.uk [TPRU, Birkbeck College, University of London, London, WC1E 7HX (United Kingdom)

    2015-06-26

    Highlights: • The quantum potential is seen as internal energy associated with a phase space region. • Fermi's trick shows that Bohm's particle is an extended structure in phase space. • We associate Bohm's quantum potential with a context-dependent energy redistribution. • A physically motivated derivation of Schrodinger's equation is provided. • We show the Fermi set associated with a 3-D coherent state contains a quantum blob. - Abstract: We pursue our discussion of Fermi's surface initiated by Dennis, de Gosson and Hiley and show that Bohm's quantum potential can be viewed as an internal energy of a quantum system, giving further insight into its role in stationary states. This implies that the ‘particle’ referred to in Bohm's theory is not a classical point-like object but rather has an extended structure in phase space which can be linked to the notion of a symplectic capacity, a topological feature of the underlying symplectic geometry. This structure provides us with a new, physically motivated derivation of Schrödinger's equation provided we interpret Gleason's theorem as a derivation of the Born rule from fundamental assumptions about quantum probabilities.

  2. Maintaining International Peace and Security: Reflections on Peace ...

    African Journals Online (AJOL)

    Maintaining International Peace and Security: Reflections on Peace-Support Operations in Africa. DR THEO NEETHLING. Centrefor Military Studies, University of Stellenbosch. ABSTRACT. The shift from a bipolar to a multipolar and multi-faceted world has reduced the risk of conventional inter-state wars, but has been the ...

  3. Revisit: A Surprising Demonstration of Total Internal Reflection

    Science.gov (United States)

    Lee, Jiwon; Cha, Yu Wha; Jung, Yeon Su; Oh, Eun Ju; Moon, Ye Lin; Kim, Jung Bog

    2016-01-01

    Melton demonstrated a surprising disappearance using total internal reflection. When he put a Florence flask filled with marbles into a water tank and looked straight down from directly above the flask, he was only able to see marbles above a certain water level. When he added more water into the tank above the top line of the marbles, all of the…

  4. Gaining Insight into Antibubbles via Frustrated Total Internal Reflection

    Science.gov (United States)

    Suhr, Wilfried

    2012-01-01

    The interest in the phenomenon of frustrated total internal reflection dates back to the time of Newton. Because of its technological relevance, it has become a standard topic covered by advanced courses in physics. In practical courses optical setups especially designed to demonstrate the phenomenon are commonly used. As an alternative, this…

  5. Double conoscopic figures in total-internal-reflection prisms

    Science.gov (United States)

    Litvinova, M. N.; Stroganov, V. I.; Krishtop, V. V.; Alekseeva, L. V.; Pas'ko, P. G.

    2006-01-01

    This paper presents the results of a study of the features of the formation of double conoscopic figures in total-internal-reflection prisms. The conditions for the existence of double conoscopic figures in the absence of a polarizer and analyzer are explained. An experiment has been done with prisms fabricated from crystals of calcite, potassium dihydrogen phosphate (KDP) and lithium niobate.

  6. International Student Teaching: Stimulus for Developing Reflective Teachers.

    Science.gov (United States)

    Vall, Nancy Gerdin, Tennison, Jo M.

    1992-01-01

    Discusses how culture shock intrinsic in a cross-cultural student teaching experience necessitates that participants think critically and reflect about teaching. The article describes an international student teaching component at two Minnesota colleges. After 7 weeks of student teaching in the United States, participants spend 6 weeks in British…

  7. Thin-film-based sensitivity enhancement for total internal reflection fluorescence live-cell imaging.

    Science.gov (United States)

    Kim, Kyujung; Cho, Eun-Jin; Huh, Yong-Min; Kim, Donghyun

    2007-11-01

    We investigated experimentally the evanescent field enhancement based on dielectric thin films in total internal reflection microscopy. The sample employed two layers of Al2O3 and SiO2 deposited on an SF10 glass substrate. Field intensity enhancement measured by fluorescent excitation of microbeads relative to that of a control sample without dielectric films was polarization dependent, determined as 4.2 and 2.4 for TE and TM polarizations, respectively, and was in good agreement with numerical results. The thin-film-based field enhancement was also applied to live-cell imaging of quantum dots, which confirmed the sensitivity enhancement qualitatively.

  8. Nanograting-based plasmon enhancement for total internal reflection fluorescence microscopy of live cells

    International Nuclear Information System (INIS)

    Kim, Kyujung; Cho, Eun-Jin; Suh, Jin-Suck; Huh, Yong-Min; Kim, Donghyun; Kim, Dong Jun

    2009-01-01

    We investigated evanescent field enhancement based on subwavelength nanogratings for improved sensitivity in total internal reflection microscopy of live cells. The field enhancement is associated with subwavelength-grating-coupled plasmon excitation. An optimum sample employed a silver grating on a silver film and an SF10 glass substrate. Field intensity was enhanced by approximately 90% when measured by fluorescent excitation of microbeads relative to that on a bare prism as a control, which is in good agreement with numerical results. The subwavelength-grating-mediated field enhancement was also applied to live cell imaging of quantum dots, which confirmed the sensitivity enhancement qualitatively.

  9. Quantum resonances in reflection of relativistic electrons and positrons

    International Nuclear Information System (INIS)

    Eykhorn, Yu.L.; Korotchenko, K.B.; Pivovarov, Yu.L.; Takabayashi, Y.

    2015-01-01

    Calculations based on the use of realistic potential of the system of crystallographic planes confirm earlier results on existence of resonances in reflection of relativistic electrons and positrons by the crystal surface, if the crystallographic planes are parallel to the surface.The physical reason of predicted phenomena, similar to the band structure of transverse energy levels, is connected with the Bloch form of the wave functions of electrons (positrons) near the crystallographic planes, which appears both in the case of planar channeling of relativistic electrons (positrons) and in reflection by a crystal surface. Calculations show that positions of maxima in reflection of relativistic electrons and positrons by crystal surface specifically depend on the angle of incidence with respect to the crystal surface and relativistic factor of electrons/positrons. These maxima form the Darwin tables similar to that in ultra-cold neutron diffraction

  10. Quantum propagator in the presence of a perfectly reflecting wall

    International Nuclear Information System (INIS)

    Cacciari, Ilaria; Lantieri, Marco; Moretti, Paolo

    2007-01-01

    The transmission propagator for an arbitrary, finite range one-dimensional potential in the presence of a perfectly reflecting wall is calculated starting from the integral form of the Schroedinger equation. After a Laplace transform, the solution is obtained in a new and simple form by using matrix methods; we apply the results to an array of delta potentials

  11. New prism ring laser design incorporating frustrated total internal reflection output coupling

    DEFF Research Database (Denmark)

    Heyde, C.; Hansen, P.L.; Buchhave, Preben

    1997-01-01

    A novel prism ring laser design incorporating total internal reflection resonator mirrors and frustrated total internal reflection output coupling is analyzed and tested experimentally.......A novel prism ring laser design incorporating total internal reflection resonator mirrors and frustrated total internal reflection output coupling is analyzed and tested experimentally....

  12. Nonlocal transformation of the internal quantum particle structure

    Directory of Open Access Journals (Sweden)

    Alexey Yu. Samarin

    2016-09-01

    Full Text Available The analysis of the integral wave equation, having path integral kernel, has resulted, that collapse phenomenon is based on the nonlocal transformation of the internal structure of a quantum particle, considering in the form of the matter fields collection. This nonlocality allows to escape the contradiction between the reduction quantum mechanics postulate and special relativity. It is shown, that the wave function transformation, corresponding to von Neumann's reduction, has the deterministic nature and the quantum mechanics stochasticity is a consequence of a macroscopic measurer presence in the measuring process. Besides it is demonstrated, that the decogerence phenomenon has the same mechanism of the wave function transformation. EPR-type experiment is described in detail and the possibility of the faster-then light communication is proved, as well the possible rules of thumb of this communication are proposed.

  13. Quantum Yield of Reflection Mode Varied Doping GaN Photocathode

    Directory of Open Access Journals (Sweden)

    Qiao Jianliang

    2016-01-01

    Full Text Available Using the NEA photocathode activation and evaluation experiment system, the varied doping GaN photocathode has been activated and evaluated. According to the diffusion and orientation drifting equation, the quantum yield formula of reflection mode varied doping NEA GaN photocathode was gotten. The factors affecting the quantum efficiency of varied doping GaN photocathode were studied. For the varied doping GaN photocathode, the quantum efficiency is mainly decided by the escape probability of electron P, he absorption coefficient α, the electron diffuse length LD, the reflectance of cathode materials for incident light R, emission layer thickness Te and the inside electric field E. The experiment and analysis results show: With the directional inside electric field in the bulk, the varied doping NEA GaN photocathode has better photoemission performance than uniform doping photocathode.

  14. Generation of paired photons in a quantum separable state in Bragg reflection waveguides

    Czech Academy of Sciences Publication Activity Database

    Svozilík, Jiří; Hendrych, Martin; Helmy, A.S.; Torres, J.P.

    2011-01-01

    Roč. 19, č. 4 (2011), s. 3115-3123 ISSN 1094-4087 R&D Projects: GA MŠk(CZ) OC09026; GA AV ČR IAA100100713 Institutional research plan: CEZ:AV0Z10100522 Keywords : photon pair * quantum state * Bragg reflection waveguides Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.587, year: 2011

  15. Internal quantum efficiency enhancement of GaInN/GaN quantum-well structures using Ag nanoparticles

    International Nuclear Information System (INIS)

    Iida, Daisuke; Fadil, Ahmed; Ou, Yiyu; Kopylov, Oleksii; Ou, Haiyan; Chen, Yuntian; Iwaya, Motoaki; Takeuchi, Tetsuya; Kamiyama, Satoshi; Akasaki, Isamu

    2015-01-01

    We report internal quantum efficiency enhancement of thin p-GaN green quantum-well structure using self-assembled Ag nanoparticles. Temperature dependent photoluminescence measurements are conducted to determine the internal quantum efficiency. The impact of excitation power density on the enhancement factor is investigated. We obtain an internal quantum efficiency enhancement by a factor of 2.3 at 756 W/cm 2 , and a factor of 8.1 at 1 W/cm 2 . A Purcell enhancement up to a factor of 26 is estimated by fitting the experimental results to a theoretical model for the efficiency enhancement factor

  16. DIRC, the internally reflecting ring imaging Cherenkov detector for BABAR

    International Nuclear Information System (INIS)

    Adam, I.; Aston, D.

    1997-11-01

    The DIRC is a new type of Cherenkov imaging device that will be used for the first time in the BABAR detector at the asymmetric B-factory, PEP-II. It is based on total internal reflection and uses long, rectangular bars made from synthetic fused silica as Cherenkov radiator and light guide. The principles of the DIRC ring imaging Cherenkov technique are explained and results from the prototype program are presented. Its choice for the BABAR detector particle identification system is motivated, followed by a discussion of the quartz radiator properties and the detector design

  17. Democracy of internal symmetries in supersymmetrical quantum field theory

    Energy Technology Data Exchange (ETDEWEB)

    Lopuszanski, J.T.

    1981-12-01

    The freedom of choice of some discrete and internal symmetries in the supersymmetric, massive, interacting quantum field theory is discussed. It is shown that the discrete symmetry consisting of changing the sign of some (not all) scalar fields is incompatible with the supersymmetric structure of the theory. It is further demonstrated that an internal symmetry which transforms only some of the fields of fixed spin leaving the other fields invariant and which acts nontrivially on the supercharges can not be admitted as a symmetry; although it can be a good internal symmetry in absence of supersymmetric covariance. Moreover, in case of a model consisting of scalar, spinor and vector fields even a symmetry which transforms all of the scalar (vector) fields leaving spinor and vector (scalar) fields unaffected is ruled out provided it acts nontrivially on some of the supercharges.

  18. Role of the substrate reflectance and surface-bulk treatments in CsI quantum efficiency

    CERN Document Server

    Singh, B K; Nitti, M A; Valentini, A

    2003-01-01

    We have experimentally investigated the following aspects related to the quantum efficiency of CsI photocathodes: the type of substrate, the film thickness and the effect of a 'bulk treatment' during the film growth. We discovered that, using a high reflectivity aluminium substrate, the photoemission of very thin CsI film is enhanced. Our study also revealed that photocathodes become less sensitive to moisture when a negative bias voltage is applied to the substrate during the film deposition process.

  19. Total Internal Reflection Fluorescence Quantification of Receptor Pharmacology

    Directory of Open Access Journals (Sweden)

    Ye Fang

    2015-04-01

    Full Text Available Total internal reflection fluorescence (TIRF microscopy has been widely used as a single molecule imaging technique to study various fundamental aspects of cell biology, owing to its ability to selectively excite a very thin fluorescent volume immediately above the substrate on which the cells are grown. However, TIRF microscopy has found little use in high content screening due to its complexity in instrumental setup and experimental procedures. Inspired by the recent demonstration of label-free evanescent wave biosensors for cell phenotypic profiling and drug screening with high throughput, we had hypothesized and demonstrated that TIRF imaging is also amenable to receptor pharmacology profiling. This paper reviews key considerations and recent applications of TIRF imaging for pharmacology profiling.

  20. Proceedings of the international colloquium on modern quantum field theory II

    International Nuclear Information System (INIS)

    Das, S.R.; Mandal, G.; Mukhi, S.; Wadia, S.R.

    1995-01-01

    In the second International Colloquium on Modern Quantum Field Theory an attempt was made to cover a broad spectrum of topics in theoretical physics that included string theory, quantum gravity, statistical mechanics, condensed matter theory, complexity, lattice gauge theory and epistemological aspects of quantum mechanics. Papers relevant to INIS in the published proceedings are indexed separately

  1. Investigation of the internal reflectance and prediction of infrared diffuse reflectance of the polymeric coating on aluminum substrate

    Science.gov (United States)

    Ho, Wen-Dar; Ma, Chen-Chi M.

    1998-02-01

    This study employs the ray tracing method to develop and analyze mathematical formulae for the IR diffuse reflectance of the polymeric coating on a metal substrate. The effects of the thickness and the absorption property of the polymer film on the internal reflectance are also investigated. In addition, the diffuse reflectance of the coating/substrate system which is irradiated with a perfect diffuse source is formulated as well. Analysis results indicate that the internal reflectance of the internal front surface (polymer/air interface) is not a constant which depends on the film thickness and absorption property. Closely examining the internal multiple reflections between the front and the substrate surface reveals that the diffuse reflectance of the coating/substrate system can be obtained by summing the fractions of rays emerging from the front surface. By knowing the refractive index and the extinction coefficient of the polymer, the diffuse reflectance of the coating/substrate system can be calculated by the formulae presented here. In addition an alkyd resin coating/aluminum substrate system is also implemented to compare the experimental reflectances with the calculated ones. According to the comparisons the analysis and developed formulae are quite effective.

  2. Value of Online Group Reflection After International Service-Learning Experiences: I Never Thought of That.

    Science.gov (United States)

    Smit, Eileen M; Tremethick, Mary Jane

    Reflection is a widely accepted learning tool and a component of competent professional practice. An exploratory descriptive study was conducted to compare the breadth and level of reflection between students engaged in individual reflection papers and students engaged in an online group reflection discussion after an international cultural immersion service-learning program. Results indicated that students participating in the online group discussion had a higher level of reflective thinking and discussed more topics in their written reflections.

  3. New view on quantum process of tunneling: character times for passing and reflection

    International Nuclear Information System (INIS)

    Chuprikov, N.L.

    2006-01-01

    As discussed earlier, scattering of a quantum particle at one-dimensional potential barrier should be regarded as a combined process involving two alternative elementary processes, namely: passing and reflection. For the symmetrical potential barriers one has found solutions of the Schroedinger equation that describe processes of passing and reflection throughout scattering phases. Here one deals with time aspects of both processes. For each of them one determined (the local and the asymptotic) group time periods of tunneling, dwelling time and the Larmor time of tunneling. The group time periods of tunneling should be considered as the auxiliary ones. In regard to the dwelling time and the Larmor time, they provide more precise evaluation (anticipated value) of time of stay near the barrier for a quantum particle both in the stationary and in the local nonstationary states. In this case, the Larmor time is just the dwelling time averaged over the appropriate ensemble of particles. The mentioned characteristic may be changed experimentally and, thus, the described model of scattering is a verifiable one [ru

  4. Visualization of quantum turbulence in superfluid 3He-B : Combined numerical and experimental study of Andreev reflection

    Science.gov (United States)

    Tsepelin, V.; Baggaley, A. Â. W.; Sergeev, Y. Â. A.; Barenghi, C. Â. F.; Fisher, S. Â. N.; Pickett, G. Â. R.; Jackson, M. Â. J.; Suramlishvili, N.

    2017-08-01

    We present a combined numerical and experimental study of Andreev scattering from quantum turbulence in superfluid 3He-B at ultralow temperatures. We simulate the evolution of moderately dense, three-dimensional, quasiclassical vortex tangles and the Andreev reflection of thermal quasiparticle excitations by these tangles. This numerical simulation enables us to generate the two-dimensional map of local Andreev reflections for excitations incident on one of the faces of a cubic computational domain, and to calculate the total coefficient of Andreev reflection as a function of the vortex line density. Our numerical simulation is then compared with the experimental measurements probing quantum turbulence generated by a vibrating grid. We also address the question of whether the quasiclassical and ultraquantum regimes of quantum turbulence can be distinguished by their respective total Andreev reflectivities. We discuss the screening mechanisms which may strongly affect the total Andreev reflectivity of dense vortex tangles. Finally, we present combined numerical-experimental results for fluctuations of the Andreev reflection from a quasiclassical turbulent tangle and demonstrate that the spectral properties of the Andreev reflection reveal the nature and properties of quantum turbulence.

  5. Proceedings of Waseda international symposium on fundamental physics. New perspectives in quantum physics

    International Nuclear Information System (INIS)

    Ohba, Ichiro; Aizawa, Yoji; Daishido, Tsuneaki; Kurihara, Susumu; Maeda, Kei-ichi; Nakazato, Hiromichi; Tasaki, Shuichi; Yuasa, Kazuya

    2003-11-01

    Waseda International Symposium on Fundamental Physics - New Perspectives in Quantum Physics - was held on November 12-15, 2002 at International Conference Hall (IBUKA HALL), Waseda University, Tokyo, Japan. This symposium was organized to provide an opportunity to verify fundamental physics attainments and to discuss new prospectives in quantum physics in the 21st century. These themes of the symposium were reexamined from all aspects in terms of important key words of the symposium, fundamental quantum theory, quantum coherence and decoherence, quantum chaos, time symmetry breaking, Bose-Einstein condensation and quantum information and computation. Separate abstracts were presented for 12 of the papers in this report. The remaining 40 were considered outside the subject scope of INIS. (J.P.N.)

  6. An Arduino-Based Experiment Designed to Clarify the Transition to Total Internal Reflection

    Science.gov (United States)

    Atkin, Keith

    2018-01-01

    The topic of refraction and reflection of light at the boundary of transparent media is a fundamentally important one. The special case of total internal reflection is however commonly misrepresented in elementary textbooks. This paper addresses the problem and describes an experimental procedure for measuring and displaying reflected and…

  7. An Arduino-based experiment designed to clarify the transition to total internal reflection

    Science.gov (United States)

    Atkin, Keith

    2018-03-01

    The topic of refraction and reflection of light at the boundary of transparent media is a fundamentally important one. The special case of total internal reflection is however commonly misrepresented in elementary textbooks. This paper addresses the problem and describes an experimental procedure for measuring and displaying reflected and transmitted light intensities using readily available components and the Arduino microcontroller.

  8. Quantum field theory and the internal states of elementary particles

    CSIR Research Space (South Africa)

    Greben, JM

    2011-01-01

    Full Text Available satisfying coupled quantum field equations, all expressed at the same space-time coordinate. Quantization is realized by expanding the quantum fields in terms of fermionic creation and annihilation operators. This approach is applied in a QCD description...

  9. Reflections on the law applicable to international oil contracts

    OpenAIRE

    Otero García-Castrillón, Carmen

    2013-01-01

    Business activity in the hydrocarbon sector, involving the extraction of natural resources essential to maintain our modern lifestyle, begins with the negotiation of oil and gas exploration and exploitation contracts. Apart from the traditional role of the parties’ contractual autonomy, determining the legal regime of these contracts necessitates considering the role of international law, the development of oil sector-specific international rules (lex petrolea), and the impact of the imperati...

  10. 15th International Conference on Non-Hermitian Hamiltonians in Quantum Physics

    CERN Document Server

    Passante, Roberto; Trapani, Camillo

    2016-01-01

    This book presents the Proceedings of the 15th International Conference on Non-Hermitian Hamiltonians in Quantum Physics, held in Palermo, Italy, from 18 to 23 May 2015. Non-Hermitian operators, and non-Hermitian Hamiltonians in particular, have recently received considerable attention from both the mathematics and physics communities. There has been a growing interest in non-Hermitian Hamiltonians in quantum physics since the discovery that PT-symmetric Hamiltonians can have a real spectrum and thus a physical relevance. The main subjects considered in this book include: PT-symmetry in quantum physics, PT-optics, Spectral singularities and spectral techniques, Indefinite-metric theories, Open quantum systems, Krein space methods, and Biorthogonal systems and applications. The book also provides a summary of recent advances in pseudo-Hermitian Hamiltonians and PT-symmetric Hamiltonians, as well as their applications in quantum physics and in the theory of open quantum systems.

  11. Transmission and reflection of charge-density wave packets in a quantum Hall edge controlled by a metal gate

    Science.gov (United States)

    Matsuura, Masahiro; Mano, Takaaki; Noda, Takeshi; Shibata, Naokazu; Hotta, Masahiro; Yusa, Go

    2018-02-01

    Quantum energy teleportation (QET) is a proposed protocol related to quantum vacuum. The edge channels in a quantum Hall system are well suited for the experimental verification of QET. For this purpose, we examine a charge-density wave packet excited and detected by capacitively coupled front gate electrodes. We observe the waveform of the charge packet, which is proportional to the time derivative of the applied square voltage wave. Further, we study the transmission and reflection behaviors of the charge-density wave packet by applying a voltage to another front gate electrode to control the path of the edge state. We show that the threshold voltages where the dominant direction is switched in either transmission or reflection for dense and sparse wave packets are different from the threshold voltage where the current stops flowing in an equilibrium state.

  12. Accompanying Partners of International Students: Reflections on Three Issues

    Science.gov (United States)

    Cui, Dan; Arthur, Nancy; Domene, José F.

    2017-01-01

    This paper reviews and critiques the existing literature on accompanying partners of international students (APIS), who are often an ignored population in programs and services for the internationalization of Canadian higher education. Particularly, we identify three issues. First, we argue that current research on this group overwhelmingly…

  13. Maintaining International Peace and Security: Reflections on Peace ...

    African Journals Online (AJOL)

    produced a dramatic growth in peacekeeping requirements since the end of the previous decade. The international response, mainly through the United Nations (UN), has been to promote preventive diplomacy and, in a number of cases, to conduct peace-support operations. In brief, this paper points out that each UN ...

  14. Pedagogical Reflections on Internalizing Geopolitical Representations in Print Media

    Science.gov (United States)

    Abdul-Jabbar, Wisam Khalid

    2015-01-01

    This essay explores how print media conceals implicit hegemonic texts that common readers unsuspectingly tend to internalize. These geopolitically infused texts are set to appropriate the reader's worldviews by sublimating the kind of perceptions and notions they want to promote. This paper raises questions and awareness about how academia…

  15. Effect of the refraction factor of a plastic fiber shell on the internal reflection coefficient

    International Nuclear Information System (INIS)

    Pkrksypkin, A.I.; Ponomarev, L.I.

    1992-01-01

    Results of pilot studies of the effect of refraction factor of plastic fiber shell on the coefficient of light internal reflection in the fiber are presented. It is pointed, that the shell does not absorb the light, but effects the surface layer of the fiber centre so, that dependence of the coefficient of internal reflection on refraction factor of the shell may be described using Fresnel formulae. It is shown, that coefficient of internal reflection decreases with the increase of refraction factor. Technique to determine volume length of scintillation light absorption in the fiber is suggested

  16. Reflections on the development of international nuclear law

    International Nuclear Information System (INIS)

    Lamm, Vanda

    2017-01-01

    Over the course of more than seven decades, treaty norms on the production and utilisation of nuclear energy have been developed, which together form a special section within international law. These norms are the consequence of the unique nature of the field, namely that on the one hand some aspects of the uses of nuclear energy should be covered by totally new and special norms (e.g. in the field of disarmament, seeking to eliminate or at least to control the spread of nuclear weapons, and nuclear weapons tests) and on the other hand that several traditional legal solutions were not suitable for the problems that emerged in connection with other uses of nuclear energy (like liability). In this article, three aspects of the development of that special section of international law will be explored, namely: the close connections between the regulation of peaceful and military uses of nuclear energy; the effects of nuclear catastrophes on the development of international nuclear legislation; and the interaction between soft law norms and binding norms in the area of nuclear law

  17. PREFACE: International Conference on Quantum Simulators and Design, Hiroshima, Japan, 3 6 December 2006

    Science.gov (United States)

    Akai, Hisazumi; Oguchi, Tamio

    2007-09-01

    This special issue of Journal of Physics: Condensed Matter comprises selected papers from the 1st International Conference on Quantum Simulators and Design (QSD2006) held in Hiroshima, Japan, 3-6 December 2006. This conference was organized under the auspices of the Development of New Quantum Simulators and Quantum Design Grant-in-Aid for Scientific Research on Priority Areas, Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT), and Hiroshima University Quantum design is a computational approach to the development of new materials with specified properties and functionalities. The basic ingredient is the use of quantum simulations to design a material that meets a given specification of properties and functionalities. For this to be successful, the quantum simulation should be highly reliable and be applicable to systems of realistic size. A central interest is, therefore, the development of new methods of quantum simulation and quantum design. This includes methods beyond the local density approximation of density functional theory (LDA), order-N methods, methods dealing with excitations and reactions, and so on, as well as the application of these methods to the design of new materials and devices. The field of quantum design has developed rapidly in the past few years and this conference provides an international forum for experimental and theoretical researchers to exchange ideas. A total of 183 delegates from 8 countries participated in the conference. There were 18 invited talks, 16 oral presentations and 100 posters. There were many new ideas and we foresee dramatic progress in the coming years. The 2nd International Conference on Quantum Simulators and Design will be held in Tokyo, Japan, 31 May-3 June 2008.

  18. Nursing student voices: reflections on an international service learning experience.

    Science.gov (United States)

    Main, E Eve; Garrett-Wright, Dawn; Kerby, Molly

    2013-01-01

    For the past decade participation in service and experiential learning in higher education has increased. The purpose of this study was to explore the lived experience of BSN and MSN students participating in a multidisciplinary service-learning course in a rural, underserved village in Belize. Researchers analyzed student journals utilizing qualitative data analysis techniques. There were eight consistent themes found in the student journals. The findings indicate that international service learning opportunities increase students' awareness of their place in a global society and the potential contribution they can make in society. For the past decade, service and experiential learning in higher education, including nursing education, has become increasingly important. Simply put, service and experiential learning combine community service activities with a student's academic study for the sole purpose of enriching the academic experience. As faculty, we feel the goal of baccalaureate and graduate nursing education is to produce an educated professional who will become a responsible citizen.

  19. Pedagogical Reflections on Internalizing Geopolitical Representations in Print Media

    Directory of Open Access Journals (Sweden)

    Wisam Khalid Abdul-Jabbar

    2015-06-01

    Full Text Available This essay explores how print media conceals implicit hegemonic texts that common readers unsuspectingly tend to internalize. These geopolitically infused texts are set to appropriate the reader’s worldviews by sublimating the kind of perceptions and notions they want to promote. This paper raises questions and awareness about how academia responds to these acts of internalization. These geopolitical texts, which dominate most of the print media and other resources, function at an imperceptible level to legitimize presuppositions and mould the world based on its own political imaginaries. To decode and interpret these largely shrewd texts requires a literacy skill that students need to acquire in different academic disciplines. This essay, therefore, explores how print media, such as newspapers and comics, attempts to legitimize knowledge through reports and stories that work at the subliminal level. Since all readers, students, instructors or researchers are vulnerable observers (Behar, 1996, because of our fallible human nature, the act of internalizing mediascaped knowledge becomes alarmingly simple and crucially effective on the way we are directed to perceive the world. By analogy, geopolitical texts are these id-instigated drives that the superego often suppresses and filters into dreams and fiction and yet they ominously somehow found their way out; they stealthily found expression and now they paint reality with their own biased colors. Can readers in the context be dream catchers? Cet article explore la manière dont les médias écrits dissimulent les textes hégémoniques implicites que les lecteurs ordinaires semblent assimiler à leur insu. Ces textes géopolitiquement insufflés sont appelés à approprier la vision du monde des lecteurs en sublimant le type de perceptions et de notions qu’ils souhaitent promouvoir. Cet article soulève des questions et sensibilise l’opinion sur la manière dont le monde universitaire r

  20. International Trade and Sustainable Development: Reflections on the Regulation Through the International Organizations

    OpenAIRE

    Barza, Eugênia Cristina Nilsen Ribeiro; Cerqueira, Wanilza Marques de Almeida

    2016-01-01

    The purpose of this study is to analyze the link between international trade and development. The regulation of international trade by international organizations will be explored. In the post-WTO scenario, there is the formation of a new governance in relation to international trade, with a tendency to appreciation of international relations at the Westphalian style. This phenomenon is worrying , especially in light of Agenda 2030 for Sustainable Development and the 17 Sustainable Developmen...

  1. International Trade and Sustainable Development: Reflections on the Regulation Through the International Organizations

    Directory of Open Access Journals (Sweden)

    Eugênia Cristina Nilsen Ribeiro Barza

    2016-12-01

    Full Text Available The purpose of this study is to analyze the link between international trade and development. The regulation of international trade by international organizations will be explored. In the post-WTO scenario, there is the formation of a new governance in relation to international trade, with a tendency to appreciation of international relations at the Westphalian style. This phenomenon is worrying , especially in light of Agenda 2030 for Sustainable Development and the 17 Sustainable Development Goals established by the UN, which require a multilateral regulation of trade and participation of international organizations , particularly the WTO , for implementation their goals.

  2. Equivalent Method of Solving Quantum Efficiency of Reflection-Mode Exponential Doping GaAs Photocathode

    International Nuclear Information System (INIS)

    Jun, Niu; Zhi, Yang; Ben-Kang, Chang

    2009-01-01

    The mathematical expression of the electron diffusion and drift length L DE of exponential doping photocathode is deduced. In the quantum efficiency equation of the reffection-mode uniform doping cathode, substituting L DE for L D , the equivalent quantum efficiency equation of the reffection-mode exponential doping cathode is obtained. By using the equivalent equation, theoretical simulation and experimental analysis shows that the equivalent index formula and formula-doped cathode quantum efficiency results in line. The equivalent equation avoids complicated calculation, thereby simplifies the process of solving the quantum efficiency of exponential doping photocathode

  3. NATO Advanced Study Institute on International Summer School on Chaotic Dynamics and Transport in Classical and Quantum Systems

    CERN Document Server

    Collet, P; Métens, S; Neishtadt, A; Zaslavsky, G; Chaotic Dynamics and Transport in Classical and Quantum Systems

    2005-01-01

    This book offers a modern updated review on the most important activities in today dynamical systems and statistical mechanics by some of the best experts in the domain. It gives a contemporary and pedagogical view on theories of classical and quantum chaos and complexity in hamiltonian and ergodic systems and their applications to anomalous transport in fluids, plasmas, oceans and atom-optic devices and to control of chaotic transport. The book is issued from lecture notes of the International Summer School on "Chaotic Dynamics and Transport in Classical and Quantum Systems" held in Cargèse (Corsica) 18th to the 30th August 2003. It reflects the spirit of the School to provide lectures at the post-doctoral level on basic concepts and tools. The first part concerns ergodicity and mixing, complexity and entropy functions, SRB measures, fractal dimensions and bifurcations in hamiltonian systems. Then, models of dynamical evolutions of transport processes in classical and quantum systems have been largely expla...

  4. International Workshop on "Intersubband Transitions in Quantum Wells : Physics and Applications"

    CERN Document Server

    Su, Yan-Kuin

    1998-01-01

    The International Workshop on "Intersubband Transitions in Quantum Wells:: Physics and Applications," was held at National Cheng Kung University, in Tainan, Taiwan, December 15-18, 1997. The objective of the Workshop is to facilitate the presentation and discussion of the recent results in theoretical, experimental, and applied aspects of intersubband transitions in quantum wells and dots. The program followed the tradition initiated at the 1991 conference in Cargese-France, the 1993 conference in Whistler, B. C. Canada, and the 1995 conference in Kibbutz Ginosar, Israel. Intersubband transitions in quantum wells and quantum dots have attracted considerable attention in recent years, mainly due to the promise of various applications in the mid- and far-infrared regions (2-30 J. lm). Over 40 invited and contributed papers were presented in this four-day workshop, with topics covered most aspects of the intersubband transition phenomena including: the basic intersubband transition processes, multiquantum well i...

  5. Equal-Spin Andreev Reflection on Junctions of Spin-Resolved Quantum Hall Bulk State and Spin-Singlet Superconductor.

    Science.gov (United States)

    Matsuo, Sadashige; Ueda, Kento; Baba, Shoji; Kamata, Hiroshi; Tateno, Mizuki; Shabani, Javad; Palmstrøm, Christopher J; Tarucha, Seigo

    2018-02-22

    The recent development of superconducting spintronics has revealed the spin-triplet superconducting proximity effect from a spin-singlet superconductor into a spin-polarized normal metal. In addition recently superconducting junctions using semiconductors are in demand for highly controlled experiments to engineer topological superconductivity. Here we report experimental observation of Andreev reflection in junctions of spin-resolved quantum Hall (QH) states in an InAs quantum well and the spin-singlet superconductor NbTi. The measured conductance indicates a sub-gap feature and two peaks on the outer side of the sub-gap feature in the QH plateau-transition regime increases. The observed structures can be explained by considering transport with Andreev reflection from two channels, one originating from equal-spin Andreev reflection intermediated by spin-flip processes and second arising from normal Andreev reflection. This result indicates the possibility to induce the superconducting proximity gap in the the QH bulk state, and the possibility for the development of superconducting spintronics in semiconductor devices.

  6. Total internal reflection resonance light scattering at solid/liquid interfaces.

    Science.gov (United States)

    Tang, Yao-Ji; Chen, Ying; Yao, Min-Na; Li, Yao-Qun

    2008-08-05

    Total internal reflection (TIR) technique is an interface-specific tool and resonance light scattering (RLS) is of high sensitivity. The combination of both approaches is introduced into the solid/liquid interface for the first time. The behaviors of mixture of TPPS and BSA at the interface have been studied with total internal reflection resonance light scattering (TIR-RLS). The preliminary experimental results indicate that TIR-RLS is a good approach to study the interaction and distinguish the states of macromolecules at the solid/liquid interface.

  7. Israeli medical education: international perspectives, and reflections on challenges and changes.

    Science.gov (United States)

    Katz, David R

    2016-01-01

    Medical education is a dynamic and continually evolving process, some of which is style, and some of which is linked to changing perspectives in medical practice. A paper by Reis et al., taken in conjunction with the recent paper from an ad hoc International Review Committee (Schoenbaum et al.), provides a reflective view of where Israeli medical education stood in 2014 and places it in an international perspective. Reis at al also take this further, showing that in Israel change is occurring as a result of this review and comment on a number of important issues where further reflection, discussion, and work is required.

  8. Internalization of targeted quantum dots by brain capillary endothelial cells in vivo.

    Science.gov (United States)

    Paris-Robidas, Sarah; Brouard, Danny; Emond, Vincent; Parent, Martin; Calon, Frédéric

    2016-04-01

    Receptors located on brain capillary endothelial cells forming the blood-brain barrier are the target of most brain drug delivery approaches. Yet, direct subcellular evidence of vectorized transport of nanoformulations into the brain is lacking. To resolve this question, quantum dots were conjugated to monoclonal antibodies (Ri7) targeting the murine transferrin receptor. Specific transferrin receptor-mediated endocytosis of Ri7-quantum dots was first confirmed in N2A and bEnd5 cells. After intravenous injection in mice, Ri7-quantum dots exhibited a fourfold higher volume of distribution in brain tissues, compared to controls. Immunofluorescence analysis showed that Ri7-quantum dots were sequestered throughout the cerebral vasculature 30 min, 1 h, and 4 h post injection, with a decline of signal intensity after 24 h. Transmission electron microscopic studies confirmed that Ri7-quantum dots were massively internalized by brain capillary endothelial cells, averaging 37 ± 4 Ri7-quantum dots/cell 1 h after injection. Most quantum dots within brain capillary endothelial cells were observed in small vesicles (58%), with a smaller proportion detected in tubular structures or in multivesicular bodies. Parenchymal penetration of Ri7-quantum dots was extremely low and comparable to control IgG. Our results show that systemically administered Ri7-quantum dots complexes undergo extensive endocytosis by brain capillary endothelial cells and open the door for novel therapeutic approaches based on brain endothelial cell drug delivery. © The Author(s) 2015.

  9. Slow-light total-internal-reflection switch with bending angle of 30 deg.

    Science.gov (United States)

    Fuchida, Ayumi; Matsutani, Akihiro; Koyama, Fumio

    2011-07-15

    Slowing light in a Bragg reflector waveguide is used to miniaturize optical waveguide switches. We can realize a giant equivalent refractive index change induced by carrier injection near a cutoff wavelength due to its large waveguide dispersion. We fabricate and characterize a reflection-type slow-light switch. Input light is reflected at the off state due to an equivalent index difference between an oxide aperture and an oxide region, while it passes through at the on state, since the equivalent index difference is compensated using carrier injection. We obtained a large bending angle of 30° with total internal reflection of slow light. © 2011 Optical Society of America

  10. Quantum spill-out in few-nanometer metal gaps: Effect on gap plasmons and reflectance from ultrasharp groove arrays

    Science.gov (United States)

    Skjølstrup, Enok J. H.; Søndergaard, Thomas; Pedersen, Thomas G.

    2018-03-01

    Plasmons in ultranarrow metal gaps are highly sensitive to the electron density profile at the metal surfaces. Using a quantum mechanical approach and assuming local response, we study the effects of electron spill-out on gap plasmons and reflectance from ultrasharp metal grooves. We demonstrate that the mode index of ultranarrow gap plasmons converges to the bulk refractive index in the limit of vanishing gap and, thereby, rectify the unphysical divergence found in classical models. Surprisingly, spill-out also significantly increases the plasmonic absorption for few-nanometer gaps and lowers the reflectance from arrays of ultrasharp metal grooves. These findings are explained in terms of enhanced gap plasmon absorption taking place inside the gap 1-2 Å from the walls and delocalization near the groove bottom. Reflectance calculations taking spill-out into account are shown to be in much better agreement with measurements compared with classical models.

  11. Quantum spill-out in few-nanometer metal gaps: Effect on gap plasmons and reflectance from ultrasharp groove arrays

    DEFF Research Database (Denmark)

    Skjølstrup, Enok Johannes Haahr; Søndergaard, Thomas; Pedersen, Thomas Garm

    2018-01-01

    Plasmons in ultranarrow metal gaps are highly sensitive to the electron density profile at the metal surfaces. Using a quantum mechanical approach and assuming local response, we study the effects of electron spill-out on gap plasmons and reflectance from ultrasharp metal grooves.We demonstrate...... that the mode index of ultranarrow gap plasmons converges to the bulk refractive index in the limit of vanishing gap and, thereby, rectify the unphysical divergence found in classical models. Surprisingly, spill-out also significantly increases the plasmonic absorption for few-nanometer gaps and lowers...... the reflectance from arrays of ultrasharp metal grooves. These findings are explained in terms of enhanced gap plasmon absorption taking place inside the gap 1–2 °A from the walls and delocalization near the groove bottom. Reflectance calculations taking spill-out into account are shown to be in much better...

  12. Celebrating international collaboration: reflections on the first Virtual International Practice Development Conference

    Directory of Open Access Journals (Sweden)

    Moira Stephens

    2016-11-01

    Full Text Available This article reports on the first Virtual International Practice Development Conference, held in May 2015 to celebrate International Nurses Day. The article describes key aspects of its planning, offers a flavour of the event itself and sets out an evaluation, including learning points and recommendations to assist with planning similar events in the future. Central to our learning are: The need for practice developers to grasp skills in technology associated with virtual space The need to embrace virtual space itself as another means by which creative and communicative spaces can be established for active learning and practice development activities The potential advantages that international virtual engagement has over face-to-face national or international engagement The delivery of this virtual event made a significant international contribution to global practice development activity within the International Practice Development Collaborative and to enabling practice developers to connect and celebrate on a more global basis. Implications for practice: Virtual space technology skills can assist with sharing and translating practice development research, innovations and critical commentary Virtual space can provide an adjunct to creative and communicative learning spaces Global networking opportunities can be developed and enhanced through the use of virtual space technology Practice developers need to role model the use of virtual technologies

  13. Creating Comic Books in Nigeria: International Reflections on Literacy, Creativity, and Student Engagement

    Science.gov (United States)

    Bitz, Michael; Emejulu, Obiajulu

    2016-01-01

    This article is an international reflection on literacy, creativity, and student engagement. The authors collaborated to help Nigerian youths and their teachers develop, design, and share original comic books. By leveraging student engagement for literacy learning, the authors highlighted the crucial role of creativity in the classroom. The…

  14. Measurement of the Longitudinal Shift of Radiation at Total Internal Reflection by Microwave Techniques

    Science.gov (United States)

    Akylas, Victor; And Others

    1976-01-01

    Describes a method to experimentally determine the longitudinal shift of a microwave beam at total internal reflection. Suggests that the activity be incorporated into an undergraduate laboratory program due to its ease in set-up and clarity of results. (CP)

  15. Four Members of the International Adult and Continuing Education Hall of Fame Reflect on Their Careers

    Science.gov (United States)

    Sandmann, Lorilee R.; Miller, Gary E.

    2011-01-01

    Drawing on collective experience of over 200 years, four members of the International Adult and Continuing Education Hall of Fame were panelists in a session at the 2010 National Outreach Scholarship Conference. As the panelists reflected on careers in the field of adult and continuing education, four sustaining themes emerged: commitment,…

  16. Symbolic Uses of Evaluation in the International Aid Sector: Arguments for Critical Reflection

    Science.gov (United States)

    McNulty, James

    2012-01-01

    Significant progress has been made in recent years to improve the quality of the evaluation of international aid. Increasingly, this includes an interest in improving the way evaluations are used to improve policies and programmes. However, the prevalence of symbolic use--a phenomenon that is often mentioned but rarely studied--reflects an…

  17. Reflections

    Indian Academy of Sciences (India)

    pumped' by displacement of the center of gravity of the person sitting or standing on it. Back in Europe (1925). In the fall of 1925 I read in some journal that an International Congress on Mechanics was to be held in. Zurichthe following autumn.

  18. PREFACE: International Symposium "Nanoscience and Quantum Physics 2011" (nanoPHYS'11)

    Science.gov (United States)

    Saito, Susumu; Tanaka, Hidekazu; Nakamura, Takashi; Nakamura, Masaaki

    2011-07-01

    Quantum physics has developed modern views of nature for more than a century. In addition to this traditional role, quantum physics has acquired new significance in the 21st century as the field responsible for driving and supporting nanoscience research, which will have even greater importance in the future because nanoscience will be the academic foundation for new technologies. The Department of Physics, Tokyo Institute of Technology, are now conducting a "Nanoscience and Quantum Physics" project (Physics G-COE project) supported by the Global Center of Excellence Program of the Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT) in order to promote research and education in these important academic fields. The International Symposium on Nanoscience and Quantum Physics, held in Tokyo, Japan, 26-28 January 2011 (nanoPHYS'11) was organized by the Physics G-COE project of the Tokyo Institute of Technology to provide an international forum for the open exchange of topical information and for stimulating discussion on novel concepts and future prospects of nanoscience and quantum physics. There were a total of 118 papers including 34 invited papers. This nanoPHYS'11 is the fourth symposium of this kind organized by the Tokyo Institute of Technology. Topics focused on in the symposium included: Category 1: Novel nanostructure (Nanowires, Nanotubes, Spin-related structure, etc) Category 2: Novel transport and electronic properties (Graphene, Topological insulators, Coherent control, etc) Category 3: Electronic and optical properties of nanostructure Category 4: Fundamental physics and new concept in quantum physics Category 5: Quantum Physics - Quantum information Category 6: Quantum Physics - Nuclear and Hadron Physics Category 7: Quantum Physics - Astrophysics, etc All the papers submitted to this issue have been reviewed under a stringent refereeing process, according to the normal rules of this Journal. The editors are grateful to all the

  19. Reflections

    Directory of Open Access Journals (Sweden)

    Joanne Embree

    2001-01-01

    Full Text Available Ideally, editorials are written one to two months before publication in the Journal. It was my turn to write this one. I had planned to write the first draft the evening after my clinic on Tuesday, September 11. It didn't get done that night or during the next week. Somehow, the topic that I had originally chosen just didn't seem that important anymore as I, along my friends and colleagues, reflected on the changes that the events of that day were likely to have on our lives.

  20. Attenuated total internal reflection infrared microspectroscopic imaging using a large-radius germanium internal reflection element and a linear array detector.

    Science.gov (United States)

    Patterson, Brian M; Havrilla, George J

    2006-11-01

    The number of techniques and instruments available for Fourier transform infrared (FT-IR) microspectroscopic imaging has grown significantly over the past few years. Attenuated total internal reflectance (ATR) FT-IR microspectroscopy reduces sample preparation time and has simplified the analysis of many difficult samples. FT-IR imaging has become a powerful analytical tool using either a focal plane array or a linear array detector, especially when coupled with a chemometric analysis package. The field of view of the ATR-IR microspectroscopic imaging area can be greatly increased from 300 x 300 microm to 2500 x 2500 microm using a larger internal reflection element of 12.5 mm radius instead of the typical 1.5 mm radius. This gives an area increase of 70x before aberrant effects become too great. Parameters evaluated include the change in penetration depth as a function of beam displacement, measurements of the active area, magnification factor, and change in spatial resolution over the imaging area. Drawbacks such as large file size will also be discussed. This technique has been successfully applied to the FT-IR imaging of polydimethylsiloxane foam cross-sections, latent human fingerprints, and a model inorganic mixture, which demonstrates the usefulness of the method for pharmaceuticals.

  1. PREFACE: XXIII International Conference on Integrable Systems and Quantum Symmetries (ISQS-23)

    Science.gov (United States)

    Burdík, Čestmír; Navrátil, Ondřej; Pošta, Severin

    2016-01-01

    The XXIII International Conference on Integrable Systems and Quantum Symmetries (ISQS-23), organized by the Department of Mathematics, Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University Prague and the Bogoliubov Laboratory of Theoretical Physics of the Joint Institute for Nuclear Research, belongs to the successful series of conferences held at the Czech Technical University which began in 1992 and is devoted to problems of mathematical physics related to the theory of integrable systems, quantum groups and quantum symmetries. During the last 20 years, each of the conferences gathered around 60 scientists from all over the world. 56 papers of plenary lectures and contributions presented at ISQS-23 are published in the present issue of Journal of Physics: Conference Series.

  2. FOREWORD: XXIst International Conference on Integrable Systems and Quantum Symmetries (ISQS21)

    Science.gov (United States)

    Burdik, Cestmir; Navratil, Ondrej; Posta, Severin

    2013-11-01

    The XXIst International Conference on Integrable Systems and Quantum symmetries (ISQS-21), organized by the Department of Mathematics, Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University Prague and the Bogoliubov Laboratory of Theoretical Physics of the Joint Institute for Nuclear Research, belongs to the successful series of conferences held at the Czech Technical University which began in 1992 and is devoted to problems of mathematical physics related to the theory of integrable systems, quantum groups and quantum symmetries. During the last 20 years, each of the conferences gathered around 60 scientists from all over the world. 36 of plenary lectures and contributions presented at ISQS-21 are published in this volume of Journal of Physics: Conference Series. Cestmir Burdik, Ondrej Navratil, Severin Posta Editors

  3. XXIV International Conference on Integrable Systems and Quantum symmetries (ISQS-24)

    Science.gov (United States)

    Burdík, Čestmír; Navrátil, Ondřej; Posta, Severin

    2017-01-01

    The XXIV International Conference on Integrable Systems and Quantum Symmetries (ISQS-24), organized by the Department of Mathematics, Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University Prague and the Bogoliubov Laboratory of Theoretical Physics of the Joint Institute for Nuclear Research, belongs to the successful series of conferences held at the Czech Technical University which began in 1992 and is devoted to problems of mathematical physics related to the theory of integrable systems, quantum groups and quantum symmetries. During the last 5 years, each of the conferences gathered around 110 scientists from all over the world. 43 papers of plenary lectures and contributions presented at ISQS-24 are published in the present issue of Journal of Physics: Conference Series.

  4. FOREWORD: XXth International Conference on Integrable Systems and Quantum Symmetries (ISQS-20)

    Science.gov (United States)

    Burdík, Čestmír; Navrátil, Ondřej; Pošta, Severin

    2013-01-01

    The XXth International Conference on Integrable Systems and Quantum Symmetries (ISQS-20), organized by the Department of Mathematics, Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University, Prague, and the Bogoliubov Laboratory of Theoretical Physics of the Joint Institute for Nuclear Research, is part of the successful series of conferences held at the Czech Technical University which began in 1992, and is devoted to problems of mathematical physics related to the theory of integrable systems, quantum groups and quantum symmetries. During the last 20 years each of these conferences has gathered around 60 scientists from all over the world. 31 plenary lectures and contributions presented at ISQS-20 are published in this volume of Journal of Physics: Conference Series. Guest Editors Čestmír Burdík, Ondřej Navrátil and Severin Pošta

  5. PREFACE: XXII International Conference on Integrable Systems and Quantum Symmetries (ISQS-22)

    Science.gov (United States)

    2014-11-01

    The XXII International Conference on Integrable Systems and Quantum symmetries (ISQS-22), organized by the Department of Mathematics, Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University Prague and the Bogoliubov Laboratory of Theoretical Physics of the Joint Institute for Nuclear Research, belongs to the successful series of conferences held at the Czech Technical University which began in 1992 and is devoted to problems of mathematical physics related to the theory of integrable systems, quantum groups and quantum symmetries. During the last 20 years, each of the conferences gathered around 60 scientists from all over the world. 33 papers of plenary lectures and contributions presented at ISQS-22 are published in the present issue of Journal of Physics: Conference Series. Čestmír Burdík, Ondřej Navrátil, Severin Pošta Editors

  6. Trapping of microwave radiation in hollow polypyrrole microsphere through enhanced internal reflection: A novel approach

    Science.gov (United States)

    Panigrahi, Ritwik; Srivastava, Suneel K.

    2015-01-01

    In present work, spherical core (polystyrene, PS)/shell (polypyrrole, PPy) has been synthesized via in situ chemical oxidative copolymerization of pyrrole (Py) on the surface of sulfonated PS microsphere followed by the formation of hollow polypyrrole (HPPy) shell by dissolving PS inner core in THF. Thereafter, we first time established that such fabricated novel art of morphology acts as a conducting trap in absorbing electromagnetic (EM) wave by internal reflection. Further studies have been extended on the formation of its silver nanocomposites HPPy/Ag to strengthen our contention on this novel approach. Our investigations showed that electromagnetic interference (EMI) shielding efficiency (SE) of HPPy (34.5-6 dB) is significantly higher compared to PPy (20-5 dB) in the frequency range of 0.5-8 GHz due to the trapping of EM wave by internal reflection. We also observed that EMI shielding is further enhanced to 59-23 in 10 wt% Ag loaded HPPy/Ag-10. This is attributed to the simultaneous contribution of internal reflection as well as reflection from outer surface. Such high EMI shielding capacity using conducting polymers are rarely reported.

  7. Significant internal quantum efficiency enhancement of GaN/AlGaN multiple quantum wells emitting at ~350 nm via step quantum well structure design

    KAUST Repository

    Wu, Feng

    2017-05-03

    Significant internal quantum efficiency (IQE) enhancement of GaN/AlGaN multiple quantum wells (MQWs) emitting at similar to 350 nm was achieved via a step quantum well (QW) structure design. The MQW structures were grown on AlGaN/AlN/sapphire templates by metal-organic chemical vapor deposition (MOCVD). High resolution x-ray diffraction (HR-XRD) and scanning transmission electron microscopy (STEM) were performed, showing sharp interface of the MQWs. Weak beam dark field imaging was conducted, indicating a similar dislocation density of the investigated MQWs samples. The IQE of GaN/AlGaN MQWs was estimated by temperature dependent photoluminescence (TDPL). An IQE enhancement of about two times was observed for the GaN/AlGaN step QW structure, compared with conventional QW structure. Based on the theoretical calculation, this IQE enhancement was attributed to the suppressed polarization-induced field, and thus the improved electron-hole wave-function overlap in the step QW.

  8. International education and reflection: transition of Swedish and American nursing students to authenticity.

    Science.gov (United States)

    Lepp, Margret; Zorn, CeCelia R; Duffy, Patricia R; Dickson, Rana J

    2003-01-01

    Reflection, a process grounded in distancing from the self to enhance self-awareness, can be used as a pedagogic activity to promote students' transition to a greater authenticity and professionalism and, therefore, improve patient care and nursing practice. In this international educational project (implemented in 2001) using interactive videoconferencing technology (IVC), Swedish and U.S. nursing students and faculty incorporated reflective journaling, drama in education, photolanguage, and off-air meeting discussions to enhance personal and professional development. Highlights from the literature, a description of the project, and student and faculty appraisals are presented.

  9. Total Internal Reflection Accounts for the Bright Color of the Saharan Silver Ant

    Science.gov (United States)

    Aron, Serge

    2016-01-01

    The Saharan silver ant Cataglyphis bombycina is one of the terrestrial living organisms best adapted to tolerate high temperatures. It has recently been shown that the hairs covering the ant’s dorsal body part are responsible for its silvery appearance. The hairs have a triangular cross-section with two corrugated surfaces allowing a high optical reflection in the visible and near-infrared (NIR) range of the spectrum while maximizing heat emissivity in the mid-infrared (MIR). Those two effects account for remarkable thermoregulatory properties, enabling the ant to maintain a lower thermal steady state and to cope with the high temperature of its natural habitat. In this paper, we further investigate how geometrical optical and high reflection properties account for the bright silver color of C. bombycina. Using optical ray-tracing models and attenuated total reflection (ATR) experiments, we show that, for a large range of incidence angles, total internal reflection (TIR) conditions are satisfied on the basal face of each hair for light entering and exiting through its upper faces. The reflection properties of the hairs are further enhanced by the presence of the corrugated surface, giving them an almost total specular reflectance for most incidence angles. We also show that hairs provide an almost 10-fold increase in light reflection, and we confirm experimentally that they are responsible for a lower internal body temperature under incident sunlight. Overall, this study improves our understanding of the optical mechanisms responsible for the silver color of C. bombycina and the remarkable thermoregulatory properties of the hair coat covering the ant’s body. PMID:27073923

  10. The role of Internal electric fields in III-N quantum structure

    International Nuclear Information System (INIS)

    Perlin, P.; Lepkowski, S.P.; Teisseyre, H.; Suski, T.

    2001-01-01

    Binary nitrides: of wurtzite GaN, AlN, InN, and their solid solutions represent family of semiconductors of crucial importance for modern optoelectronics. Strained quantum wells, like GaN/AlGaN and specially InGaN/GaN, from active layers of the light emitters working in green-UV part of spectrum. The operation of these devices strongly depends on the emission spectra of considered quantum structures which are greatly influenced by the presence of built-in electric fields. The electric field acting via quantum confined Stark effect in the mentioned structures changes the energies and intensity of the emitted light. The effect can lead to the spectral shift of a photo- and electroluminescence by many hundreds of MeV. In this review we will briefly cover the influence of internal electric fields on both optical and electrical properties of nitride based heterostructures and quantum wells. We would like to draw reader's attention to the usefulness of high-pressure investigation in the study of electric fields in nitrides and to show the interpretation of these experiments influences the way we calculate the electric fields in the quantum structures. (author)

  11. Quantum

    CERN Document Server

    Al-Khalili, Jim

    2003-01-01

    In this lively look at quantum science, a physicist takes you on an entertaining and enlightening journey through the basics of subatomic physics. Along the way, he examines the paradox of quantum mechanics--beautifully mathematical in theory but confoundingly unpredictable in the real world. Marvel at the Dual Slit experiment as a tiny atom passes through two separate openings at the same time. Ponder the peculiar communication of quantum particles, which can remain in touch no matter how far apart. Join the genius jewel thief as he carries out a quantum measurement on a diamond without ever touching the object in question. Baffle yourself with the bizzareness of quantum tunneling, the equivalent of traveling partway up a hill, only to disappear then reappear traveling down the opposite side. With its clean, colorful layout and conversational tone, this text will hook you into the conundrum that is quantum mechanics.

  12. Depth enhancement of multi-layer light field display using polarization dependent internal reflection.

    Science.gov (United States)

    Jo, Na-Young; Lim, Hong-Gi; Lee, Sung-Keun; Kim, Yong-Soo; Park, Jae-Hyeung

    2013-12-02

    A technique to enhance the depth range of the multi-layer light field three-dimensional display is proposed. A set of the optical plates are stacked in front of the conventional multi-layer light field display, creating additional internal reflection for one polarization state. By switching between two orthogonal polarization states in synchronization with the displayed three-dimensional images, the depth range of the display can be doubled. The proposed method is verified experimentally, confirming its feasibility.

  13. Trapping of microwave radiation in hollow polypyrrole microsphere through enhanced internal reflection: A novel approach

    OpenAIRE

    Ritwik Panigrahi; Suneel K. Srivastava

    2015-01-01

    In present work, spherical core (polystyrene, PS)/shell (polypyrrole, PPy) has been synthesized via in situ chemical oxidative copolymerization of pyrrole (Py) on the surface of sulfonated PS microsphere followed by the formation of hollow polypyrrole (HPPy) shell by dissolving PS inner core in THF. Thereafter, we first time established that such fabricated novel art of morphology acts as a conducting trap in absorbing electromagnetic (EM) wave by internal reflection. Further studies have bee...

  14. Exterior gauging of an internal supersymmetry and SU(2/1) quantum asthenodynamics.

    Science.gov (United States)

    Thierry-Mieg, J; Ne'eman, Y

    1982-11-01

    A formally unitary Lagrangian model gauging an internal supersymmetry is proposed. The even subalgebra is gauged as a Yang-Mills theory, while the odd generators are gauged-according to Freedman's method-by skew tensor fields, equivalent dynamically to scalar Higgs fields. Chiral fermions are incorporated by following Townsend's construction and form irreducible supermultiplets graded by their helicity. The application to quantum asthenodynamics is discussed.

  15. Specific Features of Reflection of Information Regarding Lease Operations in the National and International Standards

    Directory of Open Access Journals (Sweden)

    Nikolenko Nataliya V.

    2013-12-01

    Full Text Available The article identifies the degree of correspondence of the national Provisions (Standard of Business Accounting (PSBA Lease with the international standard and provides recommendations with respect to their closing up. On the results of the study the author provides specific features of international and national standards – the existing IFRS 17 Lease and national PSBA 14 Lease by the following components: definition of lease, its classification and reflection in accounting. Also the text of PSBA 31 Financial Expenditures is supplemented with provisions on capitalisation of financial expenditures prospectively, which would allow avoidance of correction of the balance of the retained income and provision of comparative information for previous periods. The article provides an algorithm of division of lease for accounting purposes on the basis of international standards. Its use would ensure correctness of reflection of lease operations in accounting and would serve as a basis for development of methodical provisions with respect to accounting. By the result of the study the author forms definition of the qualification asset as an asset which requires considerable time for its creation, preparation for target use, sales or acquisition of the ownership right. Capitalisation of such expenditures would allow non-reduction of the accounting income and also would provide a possibility to reflect financial expenditures in accordance with their economic essence.

  16. Quantum Theory for a Total System with One Internal Measuring Apparatus

    Science.gov (United States)

    Wang, Wen-Ge

    2011-03-01

    We propose a quantum theory for a total system including one internal measuring apparatus. The theory is based on three basic assumptions and a principle termed the principle of compatible description (PCD). The assumptions are: (i) Physical states of the total system can be associated with vectors in the Hilbert space. (ii) Dynamical evolution of a state vector obeys Schrö dinger equation. (iii) For a physical state of the total system described by a pure vector, in which a subsystem may play the role of an internal measuring apparatus, when certain stable condition is satisfied, the pure-vector description may be given a Born-type ensemble interpretation. The PCD states that different descriptions for the same state of the total system must give consistent predictions for results of measurements performed by the internal measuring apparatus. The proposed theory lies at a meeting point of Copenhagen, Everett's relative-state, and consistent-histories interpretations of quantum mechanics. While, it provides something new: For example, the PCD imposes a restriction to vectors that can be associated with physical states, which may effectively break the time-reversal symmetry of Schrödinger equation. As an application of the theory, we derive a condition under which a two-level quantum system may have definite properties, such that it may play the essential role of a measuring apparatus.

  17. Uptake, retention and internalization of quantum dots in Daphnia is influenced by particle surface functionalization

    Energy Technology Data Exchange (ETDEWEB)

    Feswick, A., E-mail: afeswick@yahoo.ca [Center for Environmental and Human Toxicology, University of Florida, PO Box 110885, Gainesville, FL 32611 (United States); Canadian Rivers Institute, University of New Brunswick, PO Box 5050, Saint John NB, CA (United States); Griffitt, R.J., E-mail: joe.griffitt@usm.edu [Department of Coastal Sciences, University of Southern Mississippi, 703 East Beach Drive, Ocean Springs, MS 39564 (United States); Siebein, K., E-mail: kerry.siebein@nist.gov [Major Analytical Instrumentation Center, University of Florida, PO Box 116400, Gainesville, FL 32611 (United States); Barber, D.S., E-mail: barberd@vetmed.ufl.edu [Center for Environmental and Human Toxicology, University of Florida, PO Box 110885, Gainesville, FL 32611 (United States)

    2013-04-15

    Highlights: ► Daphnia underwent a waterborne exposure of PEG, NH{sub 2} and COOH functionalized quantum dot nanoparticles. ► There was preferential retention of COOH nanoparticles. ► TEM demonstrated that NH{sub 2} and COOH nanoparticles were internalized in cells adjacent to the GI tract. ► This cellular internalization was confirmed using energy dispersive spectroscopy. -- Abstract: Nanomaterials are a diverse group of compounds whose inevitable release into the environment warrants study of the fundamental processes that govern the ingestion, uptake and accumulation in aquatic organisms. Nanomaterials have the ability to transfer to higher trophic levels in aquatic ecosystems, and recent evidence suggests that the surface chemistry of both the nanoparticle and biological membrane can influence uptake kinetics. Therefore, our study investigates the effect of surface functionalization on uptake, internalization and depuration in Daphnia spp. Uncharged (polyethylene glycol; PEG), positively charged (amino-terminated: NH{sub 2}) and negatively charged (carboxyl-modified; COOH) cadmium selenide/zinc sulfide quantum dots were used to monitor ingestion, uptake and depuration of nanometals in Daphnia magna and Ceriodaphnia dubia over 24 h of exposure. These studies demonstrated that particles with higher negative charge (COOH quantum dots) were taken up to a greater extent by Daphnia (259.17 ± 17.70 RFU/20 Daphnia) than either the NH{sub 2} (150.01 ± 18.91) or PEG quantum dots (95.17 ± 9.78), however this is likely related to the functional groups attached to the nanoparticles as there were no real differences in zeta potential. Whole body fluorescence associates well with fluorescent microscopic images obtained at the 24 h timepoint. Confocal and electron microscopic analysis clearly demonstrated that all three types of quantum dots could cross the intestinal epithelial barrier and be translocated to other cells. Upon cessation of exposure, elimination of

  18. Room-temperature near-field reflection spectroscopy of single quantum wells

    DEFF Research Database (Denmark)

    Langbein, Wolfgang Werner; Hvam, Jørn Marcher; Madsen, Steen

    1997-01-01

    . This technique suppresses efficiently the otherwise dominating far-field background and reduces topographic artifacts. We demonstrate its performance on a thin, strained near-surface CdS/ZnS single quantum well at room temperature. The optical structure of these topographically flat samples is due to Cd......We report on a novel optical near-field technique to measure the local polarizability of a topographically flat sample with a spatial resolution better than 100 nm. Using an uncoated fiber probe, we implement a cross-polarization detection of the optical signal at the fiber dither frequency...

  19. Relativistic coupling of internal and centre of mass dynamics in classical and simple bound quantum mechanical systems

    Science.gov (United States)

    E Krause, Dennis; Lee, Inbum

    2017-07-01

    Although special relativity and quantum mechanics revolutionised physics in the early 20th century, the consequences of combining these two theories are still being explored a hundred years later, usually using the formidable theoretical machinery of quantum field theory. However, a formalism accessible to undergraduates has been recently developed which shows how the centre of mass and internal dynamics of classical and quantum systems is relativistically coupled with interesting consequences. Here we explore some of the implications of this coupling, first classically, where we find that the dynamics of the system is time dilated when moving relative to another inertial frame. We then apply the dynamics to a quantum 2-level atom bound in a one-dimensional infinite potential well, and show that the coupling produces collapses and revivals in quantum interference. This example provides an illustration of how the combination of special relativity and quantum mechanics can be studied in situations familiar to most undergraduates.

  20. Beyond ‘Innocents Abroad’: Reflecting on Sustainability Issues During International Study Trips

    Directory of Open Access Journals (Sweden)

    Anne H. Reilly

    2016-12-01

    Full Text Available With ecosystems and populations in many regions threatened by rapid development, sustainability is a critical component for businesses in mature markets and emerging economies alike. The International Association of Jesuit Business Schools notes that global sustainability involves a broad set of interconnected issues ranging from environmental preservation to social justice to desirable production and consumption patterns. Jesuit business schools are uniquely positioned to address sustainability issues with their focus on teaching managerial content in tandem with corporate social responsibility. Further, the Ignatian Pedagogy Paradigm of experience, reflection, and action would suggest that business students may benefit from reflective observation in support of learning about sustainability. In this paper, we examine the international study trip as an opportunity for students to learn about sustainability, with results suggesting that student understanding about the broad sustainability domain may be enhanced through the study abroad experience. We discuss how two classes of primarily American MBA students traveling to emerging markets (one class to Santiago, Chile and one class to Johannesburg, South Africa were able to connect local business practices with economic and social as well as environmental sustainability issues, enhancing both student engagement and learning outcomes. Further, these students’ sustainability experiences while in an unfamiliar environment provided the opportunity to apply the potentially transformative experience, reflection, and action components of the Ignatian Pedagogy Paradigm. Compared to similar graduate business students enrolled in regular classes, we argue that these students discerned deeper connections with the economic, social, and environmental issues of sustainability.

  1. Internal-wave reflection from uniform slopes: higher harmonics and Coriolis effects

    Directory of Open Access Journals (Sweden)

    T. Gerkema

    2006-01-01

    Full Text Available Weakly nonlinear reflection of internal waves from uniform slopes produces higher harmonics and mean fields; the expressions are here derived for constant stratification and with Coriolis effects fully included, i.e. the horizontal component of the earth rotation vector (referred to as 'non-traditional'' is taken into account. Uniformity in one of the horizontal directions is assumed. It is shown that solutions can be as readily derived with as without ; hence there is no need to make the so-called Traditional Approximation. Examples of reflecting internal-wave beams are presented for super-inertial, inertial and sub-inertial frequencies. The problem of resonant and non-resonant forcing of the second harmonic is studied for single plane waves; unlike under the Traditional Approximation, the problem of reflection from a horizontal bottom no longer forms a singular case. Non-traditional effects are favourable to resonant forcing at near-tidal rather than near-inertial frequencies, and generally increase the intensity of the second harmonic. Strong stratification tends to suppress non-traditional effects, but a near-total suppression is only attained for high values of stratification that are characteristic of the seasonal thermocline; in most parts of the ocean, non-traditional effects can therefore be expected to be important.

  2. High quantum efficiency annular backside silicon photodiodes for reflectance pulse oximetry in wearable wireless body sensors

    DEFF Research Database (Denmark)

    Duun, Sune Bro; Haahr, Rasmus Grønbek; Hansen, Ole

    2010-01-01

    The development of annular photodiodes for use in a reflectance pulse oximetry sensor is presented. Wearable and wireless body sensor systems for long-term monitoring require sensors that minimize power consumption. We have fabricated large area 2D ring-shaped silicon photodiodes optimized...

  3. PREFACE: Proceedings of the 2nd International Conference on Quantum Simulators and Design (Tokyo, Japan, 31 May-3 June 2008) Proceedings of the 2nd International Conference on Quantum Simulators and Design (Tokyo, Japan, 31 May-3 June 2008)

    Science.gov (United States)

    Akai, Hisazumi; Tsuneyuki, Shinji

    2009-02-01

    This special issue of Journal of Physics: Condensed Matter comprises selected papers from the proceedings of the 2nd International Conference on Quantum Simulators and Design (QSD2008) held in Tokyo, Japan, between 31 May and 3 June 2008. This conference was organized under the auspices of the Development of New Quantum Simulators and Quantum Design Grant-in-Aid for Scientific Research on Priority Areas, Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT). The conference focused on the development of first principles electronic structure calculations and their applications. The aim was to provide an opportunity for discussion on the progress in computational materials design and, in particular, the development of quantum simulators and quantum design. Computational materials design is a computational approach to the development of new materials. The essential ingredient is the use of quantum simulators to design a material that meets a given specification of properties and functionalities. For this to be successful, the quantum simulator should be very reliable and be applicable to systems of realistic size. During the conference, new methods of quantum simulation and quantum design were discussed including methods beyond the local density approximation of density functional theory, order-N methods, methods dealing with excitations and reactions, and the application of these methods to the design of novel materials, devices and systems. The conference provided an international forum for experimental and theoretical researchers to exchange ideas. A total of 220 delegates from eight countries participated in the conference. There were 13 invited talks, ten oral presentations and 120 posters. The 3rd International Conference on Quantum Simulators and Design will be held in Germany in the autumn of 2011.

  4. Stable Single-Mode Operation of Distributed Feedback Quantum Cascade Laser by Optimized Reflectivity Facet Coatings.

    Science.gov (United States)

    Wang, Dong-Bo; Zhang, Jin-Chuan; Cheng, Feng-Min; Zhao, Yue; Zhuo, Ning; Zhai, Shen-Qiang; Wang, Li-Jun; Liu, Jun-Qi; Liu, Shu-Man; Liu, Feng-Qi; Wang, Zhan-Guo

    2018-02-02

    In this work, quantum cascade lasers (QCLs) based on strain compensation combined with two-phonon resonance design are presented. Distributed feedback (DFB) laser emitting at ~ 4.76 μm was fabricated through a standard buried first-order grating and buried heterostructure (BH) processing. Stable single-mode emission is achieved under all injection currents and temperature conditions without any mode hop by the optimized antireflection (AR) coating on the front facet. The AR coating consists of a double layer dielectric of Al 2 O 3 and Ge. For a 2-mm laser cavity, the maximum output power of the AR-coated DFB-QCL was more than 170 mW at 20 °C with a high wall-plug efficiency (WPE) of 4.7% in a continuous-wave (CW) mode.

  5. Design rule of nanostructures in light-emitting diodes for complete elimination of total internal reflection.

    Science.gov (United States)

    Son, Jun Ho; Kim, Jong Uk; Song, Yang Hee; Kim, Buem Joon; Ryu, Chul Jong; Lee, Jong-Lam

    2012-05-02

    Cone-shaped nanostructures with controllable side-wall angle are success- fully fabricated with a SiO(2) nanosphere lithography (NSL) etching mask. Vertical LEDs with cone-shaped nanostructures with a 24.1° side-wall angle provide 6% more light output power compared to those using hexagonal pyramids formed by photochemical etching. This achievement is attributed to effective elimination of total internal reflection by angle-controlled nanostructures. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Innovative light collimator with afocal lens and total internal reflection lens for daylighting system.

    Science.gov (United States)

    Chen, Bo-Jian; Chen, Yin-Ti; Ullah, Irfan; Chou, Chun-Han; Chan, Kai-Cyuan; Lai, Yi-Lung; Lin, Chia-Ming; Chang, Cheng-Ming; Whang, Allen Jong-Woei

    2015-10-01

    This research presents a novel design of the collimator, which uses total internal reflection (TIR), convex, and concave lenses for the natural light illumination system (NLIS). The concept of the NLIS is to illuminate building interiors with natural light, which saves energy consumption. The TIR lens is used to collimate the light, and convex and concave lenses are used to converge the light to the required area. The results have shown that the efficiency in terms of achieving collimated light using the proposed collimator at the output of the light collector is better than that of a previous system without a collimator.

  7. Microplate-compatible total internal reflection fluorescence microscopy for receptor pharmacology

    Science.gov (United States)

    Chen, Minghan; Zaytseva, Natalya V.; Wu, Qi; Li, Min; Fang, Ye

    2013-05-01

    We report the use of total internal reflection fluorescence (TIRF) microscopy for analyzing receptor pharmacology and the development of a microplate-compatible TIRF imaging system. Using stably expressed green fluorescence protein tagged β2-adrenergic receptor as the reporter, we found that the activation of different receptors results in distinct kinetic signatures of the TIRF intensity of cells. These TIRF signatures closely resemble the characteristics of their respective label-free dynamic mass redistribution signals in the same cells. This suggests that TIRF in microplate can be used for profiling and screening drugs.

  8. Single cell adhesion strength assessed with variable-angle total internal reflection fluorescence microscopy

    Directory of Open Access Journals (Sweden)

    Marcelina Cardoso Dos Santos

    2017-06-01

    Full Text Available We propose a new strategy to evaluate adhesion strength at the single cell level. This approach involves variable-angle total internal reflection fluorescence microscopy to monitor in real time the topography of cell membranes, i.e. a map of the membrane/substrate separation distance. According to the Boltzmann distribution, both potential energy profile and dissociation energy related to the interactions between the cell membrane and the substrate were determined from the membrane topography. We have highlighted on glass substrates coated with poly-L-lysine and fibronectin, that the dissociation energy is a reliable parameter to quantify the adhesion strength of MDA-MB-231 motile cells.

  9. International peer review in undergraduate dentistry: enhancing reflective practice in an online community of practice.

    Science.gov (United States)

    Gardner, K; Bridges, S; Walmsley, D

    2012-11-01

    To stimulate and enhance student learning in the areas of global citizenship, critical reflection and e-learning, an online international peer review using a purpose-built web platform, has been developed between international dental schools. Since its inception in 2007, n = 6 dental schools from six different countries have participated with n = 384 dental students engaged in online peer review. Project development was conceptually analysed utilising Lave and Wenger's notion of a community of practice (CoP). Analysis drew on the three core components within the CoP organising framework: domain, community and practice. All three components were evident in building project identity. The domain focused on both curriculum and institutional co-operation. The community was evident for both educators and students. Finally, analysis of practice was found to be significant in terms of sustained interaction and collaboration. Empirical evaluation is recommended as the next phase of project design. © 2012 John Wiley & Sons A/S.

  10. Spectral Separation of Quantum Dots within Tissue Equivalent Phantom Using Linear Unmixing Methods in Multispectral Fluorescence Reflectance Imaging

    Directory of Open Access Journals (Sweden)

    Ebrahim Najafzadeh

    2012-09-01

    Full Text Available Introduction Non-invasive Fluorescent Reflectance Imaging (FRI is used for accessing physiological and molecular processes in biological media. The aim of this article is to separate the overlapping emission spectra of quantum dots within tissue-equivalent phantom using SVD, Jacobi SVD, and NMF methods in the FRI mode. Materials and Methods In this article, a tissue-like phantom and an optical setup in reflectance mode were developed. The algorithm of multispectral imaging method was then written in Matlab environment. The setup included the diode-pumped solid-state lasers at 479 nm, 533 nm, and 798 nm, achromatic telescopic, mirror, high pass and low pass filters, and EMCCD camera. The FRI images were acquired by a CCD camera using band pass filter centered at 600 nm and high pass max at 615 nm for the first region and high pass filter max at 810 nm for the second region. The SVD and Jacobi SVD algorithms were written in Matlab environment and compared with a Non-negative Matrix Factorization (NMF and applied to the obtained images. Results PSNR, SNR, CNR of SVD, and NMF methods were obtained as 39 dB, 30.1 dB, and 0.7 dB, respectively. The results showed that the difference of Jacobi SVD PSNR with PSNR of NMF and modified NMF algorithm was significant (p

  11. Liability for nuclear damage: an international perspective. Reflections on the revision of the Vienna Convention

    International Nuclear Information System (INIS)

    Lopuski, J.

    1993-01-01

    This book deals with deals of the complex issues of liability and compensation for nuclear damage which have been considered in the course of the work of the IAEA concerning the revision of the Vienna Convention on nuclear liability. It presents, in an orderly way, personal reflections of its author based on his experience gathered in years 1989-1992 when participating in this work. Necessarily it contains in some of its parts references to documents of the IAEA Standing Committee on Nuclear Liability; these documents because of their length could not be reproduced. Consequently these parts may not be fully intelligible for those who have not participated in or closely followed the Committee's work. The IAEA work on liability for nuclear damage was initiated in the wake of the impact made on the world's public opinion by the Chernobyl incident and its transboundary effects; issues of international state liability and full compensation have been raised. But humanitarian ideas have quickly been confronted with cold calculations of the cost of financial protection for victims and an open unwillingness of some nuclear states has been manifested. After three years of discussions no wide consensus could be reached on some basic issues, such as: relationship between international state and civil liability regimes, structure of international legislation, concept of nuclear damage, limits of compensation, role of public funds or jurisdiction. The author presents his approach to these controversial issue, trying to provide at the same time a theoretical outline for the future international legislation on nuclear liability. (author)

  12. Determination of continuous complex refractive index dispersion of biotissue based on internal reflection

    Science.gov (United States)

    Deng, Zhichao; Wang, Jin; Ye, Qing; Sun, Tengqian; Zhou, Wenyuan; Mei, Jianchun; Zhang, Chunping; Tian, Jianguo

    2016-01-01

    The complex refractive index dispersion (CRID), which contains the information on the refractive index dispersion and extinction coefficient spectra, is an important optical parameter of biotissue. However, it is hard to perform the CRID measurement on biotissues due to their high scattering property. Continuous CRID measurement based on internal reflection (CCRIDM-IR) is introduced. By using a lab-made apparatus, internal reflectance spectra of biotissue samples at multiple incident angles were detected, from which the continuous CRIDs were calculated based on the Fresnel formula. Results showed that in 400- to 750-nm range, hemoglobin solution has complicated dispersion and extinction coefficient spectra, while other biotissues have normal dispersion properties, and their extinction coefficients do not vary much with different wavelengths. The normal dispersion can be accurately described by several coefficients of dispersion equations (Cauchy equation, Cornu equation, and Conrady equation). To our knowledge, this is the first time that the continuous CRID of scattering biotissue over a continuous spectral region is measured, and we hereby have proven that CCRIDM-IR is a good method for continuous CRID research of biotissue.

  13. Smooth and rough Proteus mirabilis lipopolysaccharides studied by total internal reflection ellipsometry

    Energy Technology Data Exchange (ETDEWEB)

    Gleńska-Olender, J., E-mail: joannaglenska@wp.pl [Institute of Biology, Jan Kochanowski University, 25-406 Kielce (Poland); Świętokrzyski Biobank, Regional Science and Technology Center, 26-060 Chęciny (Poland); Dworecki, K. [Institute of Physics, Jan Kochanowski University, 25-406 Kielce (Poland); Sęk, S. [Department of Chemistry, University of Warsaw, 02-093 Warsaw (Poland); Kwinkowski, M.; Kaca, W. [Institute of Biology, Jan Kochanowski University, 25-406 Kielce (Poland)

    2013-12-02

    Total internal reflection ellipsometry (TIRE), a label-free optical detection technique for studying interactions between biomolecules, was used to examine the adsorption of various forms of lipopolysaccharides (LPSs) isolated from Proteus mirabilis S1959, R110, and R45 strains on a gold surface. The thickness of the adsorbed layers was determined by TIRE, with the average values for S1959, R110, and R45 LPS layers being 78 ± 5, 39 ± 3, and 12 ± 2 nm, respectively. The thickness of LPS layers corresponds to the presence and length of O-specific parts in P. mirabilis LPS molecules. Atomic force microscopy was used as a complementary technique for visualizing lipopolysaccharides on the surface. Force measurements seem to confirm the data obtained from TIRE experiments. - Highlights: • Proteus mirabilis lipopolysaccharides were adsorbed on the gold surface. • Thickness of adsorbed layers was determined by total internal reflection ellipsometry. • Atomic force microscopy was used to visualize lipopolysaccharide build-up on gold surface. • Time is important in the evolution of biomolecular film thickness created on gold surface.

  14. High internal quantum efficiency in AlGaN multiple quantum wells grown on bulk AlN substrates

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, Zachary, E-mail: zabryan@ncsu.edu; Bryan, Isaac; Sitar, Zlatko; Collazo, Ramón [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Xie, Jinqiao; Mita, Seiji [HexaTech, Inc., 991 Aviation Pkwy., Suite 800, Morrisville, North Carolina 27560 (United States)

    2015-04-06

    The internal quantum efficiency (IQE) of Al{sub 0.55}Ga{sub 0.45}N/AlN and Al{sub 0.55}Ga{sub 0.45}N/Al{sub 0.85}Ga{sub 0.15}N UVC MQW structures was analyzed. The use of bulk AlN substrates enabled us to undoubtedly distinguish the effect of growth conditions, such as V/III ratio, on the optical quality of AlGaN based MQWs from the influence of dislocations. At a high V/III ratio, a record high IQE of ∼80% at a carrier density of 10{sup 18 }cm{sup −3} was achieved at ∼258 nm. The high IQE was correlated with the decrease of the non-radiative coefficient A and a reduction of midgap defect luminescence, all suggesting that, in addition to dislocations, point defects are another major factor that strongly influences optical quality of AlGaN MQW structures.

  15. Public Diplomacy and Refugee Relations Reflections of Turkey’s Refugees Relations on the International Media

    Directory of Open Access Journals (Sweden)

    Ergün Köksoy

    2015-11-01

    Full Text Available Public diplomacy is described as a new form of relations and communications between countries and societies in the field of international relations with the process of globalisation. The subject of refugees shown among the priority issues can be solved through international cooperation and solidarity with its results affecting all countries and societies, that’s why becoming part of public diplomacy. Asylum seekers and refugee rights are guaranteed by the Universal Declaration of Human Rights and considered to be an area that the international community needs to take the roles and share responsibilities. In this aspect, it is shown as global responsibilities and part of the humanitarian sensibility of countries and societies. In one hand, asylum seekers and refugees are considered to be the subject of the problem and crisis, on the other hand, due to contributing to the human and cultural interaction between the different communities, these are specified as part of public diplomacy. This article discusses the relationship between public diplomacy and refugees relations which provides the interaction between countries and effects the prestige and perception of them. In the study, to reveal the reflections of Turkey’s Refugees Relations on the International Media, three highest-circulation newspapers (“The Guardian”, “Le Monde”, “Der Spiegel” will be choosen from three important EU countries (United Kingdom, France, Germany. These newspapers’ headlines and news content which related to Turkey and Syrian refugees are going to be analized on three-month period. As a result, Turkish public diplomacy and refugee relations and its implications on the international media in the context of Syrian refugees will be evaluated and some recommendations for the future of Turkish public diplomacy and refugee relations will be provided.

  16. The International Criminal Court. reflections for a stress test on its foundations

    Directory of Open Access Journals (Sweden)

    Mateus Kowalski

    2011-01-01

    Full Text Available The constitution of the ICC in 2002 represents the ultimate example of the evolution of international criminal justice. The Court is referred to as a paradigmatic institution of the universalist concept of International Law, which envisages an enhanced international public order and which falls within the broader framework of the dominant liberal construct that currently characterizes both International Law and International Relations. However, the criticisms of universalism, in particular as regards the impositions of global liberal institutions and regulatory standards, are also reflected on the ICC. In particular, it has been met with several essential criticisms, such as its dependence on the Security Council, suggesting political interference in a criminal court, or the fact that until now only issues pertaining to Africa have been submitted to the Court, which in turn leads to suspicion about their selectivity. These are the criticisms that undermine the foundations of the ICC.At a time when the Court has not yet concluded any trial, and when there is still some scepticism about the success of its mission, knowing what to expect from the ICC in its task of crime preventing and retribution and building peace depends largely on the strength of its theoretical foundations. It is argued that despite the seemingly solid support discourse rooted in universalism, the answers advanced by this theory are not fully satisfactory due largely to the structural weaknesses that characterise it. This article seeks to offer food for thought on the subject and starts by gauging the competence of legal universalism to support “its” ICC with regard to these issues. It then identifies the aspects that can be addressed in within a more complex context, such as critical theory, which may contribute to the development of a discourse that grants the Court greater theoretical sustainability.

  17. Internal force corrections with machine learning for quantum mechanics/molecular mechanics simulations

    Science.gov (United States)

    Wu, Jingheng; Shen, Lin; Yang, Weitao

    2017-10-01

    Ab initio quantum mechanics/molecular mechanics (QM/MM) molecular dynamics simulation is a useful tool to calculate thermodynamic properties such as potential of mean force for chemical reactions but intensely time consuming. In this paper, we developed a new method using the internal force correction for low-level semiempirical QM/MM molecular dynamics samplings with a predefined reaction coordinate. As a correction term, the internal force was predicted with a machine learning scheme, which provides a sophisticated force field, and added to the atomic forces on the reaction coordinate related atoms at each integration step. We applied this method to two reactions in aqueous solution and reproduced potentials of mean force at the ab initio QM/MM level. The saving in computational cost is about 2 orders of magnitude. The present work reveals great potentials for machine learning in QM/MM simulations to study complex chemical processes.

  18. Internal force corrections with machine learning for quantum mechanics/molecular mechanics simulations.

    Science.gov (United States)

    Wu, Jingheng; Shen, Lin; Yang, Weitao

    2017-10-28

    Ab initio quantum mechanics/molecular mechanics (QM/MM) molecular dynamics simulation is a useful tool to calculate thermodynamic properties such as potential of mean force for chemical reactions but intensely time consuming. In this paper, we developed a new method using the internal force correction for low-level semiempirical QM/MM molecular dynamics samplings with a predefined reaction coordinate. As a correction term, the internal force was predicted with a machine learning scheme, which provides a sophisticated force field, and added to the atomic forces on the reaction coordinate related atoms at each integration step. We applied this method to two reactions in aqueous solution and reproduced potentials of mean force at the ab initio QM/MM level. The saving in computational cost is about 2 orders of magnitude. The present work reveals great potentials for machine learning in QM/MM simulations to study complex chemical processes.

  19. A reflecting, steepening, and breaking internal tide in a submarine canyon

    Science.gov (United States)

    Alberty, M. S.; Billheimer, S.; Hamann, M. M.; Ou, C. Y.; Tamsitt, V.; Lucas, A. J.; Alford, M. H.

    2017-08-01

    Submarine canyons are common features of the coastal ocean. Although they are known to be hotspots of turbulence that enhance diapycnal transport in their stratified waters, the dynamics of canyon mixing processes are poorly understood. Most studies of internal wave dynamics within canyons have focused on a handful of canyons with along-axis slopes less steep than semidiurnal (D2) internal wave characteristics (subcritical). Here, we present the first tidally resolving observations within a canyon with a steeply sloping axis (supercritical). A process study consisting of two 24 h shipboard stations and a profiling mooring was conducted in the La Jolla Canyon off the coast of La Jolla, CA. Baroclinic energy flux is oriented up-canyon and decreases from 182 ±18 W m-1 at the canyon mouth to 46±5 W m-1 near the head. The ratio of horizontal kinetic energy to available potential energy and the observed group speed of each mode are lower than expected for freely propagating D2 internal waves at each station, indicating partial reflection. Harmonic analysis reveals that variance is dominated by the D2 tide. Moving up-canyon, the relative importance of D2 decreases and its higher harmonics are needed to account for a majority of the observed variance, indicating steepening. Steep internal tides cause large isopycnal displacements (˜50 m in 100 m water depth) and high strain events. These events coincide with enhanced O(10-7-10-5 m2 s-3) dissipation of turbulent kinetic energy at mid-depths.

  20. Liability for nuclear damage: an international perspective. Reflections on the revision of the Vienna Convention

    Energy Technology Data Exchange (ETDEWEB)

    Lopuski, J.

    1993-12-31

    This book deals with deals of the complex issues of liability and compensation for nuclear damage which have been considered in the course of the work of the IAEA concerning the revision of the Vienna Convention on nuclear liability. It presents, in an orderly way, personal reflections of its author based on his experience gathered in years 1989-1992 when participating in this work. Necessarily it contains in some of its parts references to documents of the IAEA Standing Committee on Nuclear Liability; these documents because of their length could not be reproduced. Consequently these parts may not be fully intelligible for those who have not participated in or closely followed the Committee`s work. The IAEA work on liability for nuclear damage was initiated in the wake of the impact made on the world`s public opinion by the Chernobyl incident and its transboundary effects; issues of international state liability and full compensation have been raised. But humanitarian ideas have quickly been confronted with cold calculations of the cost of financial protection for victims and an open unwillingness of some nuclear states has been manifested. After three years of discussions no wide consensus could be reached on some basic issues, such as: relationship between international state and civil liability regimes, structure of international legislation, concept of nuclear damage, limits of compensation, role of public funds or jurisdiction. The author presents his approach to these controversial issue, trying to provide at the same time a theoretical outline for the future international legislation on nuclear liability. (author).

  1. Single-Molecule Fluorescence Studies of Membrane Transporters Using Total Internal Reflection Microscopy.

    Science.gov (United States)

    Goudsmits, Joris M H; van Oijen, Antoine M; Slotboom, Dirk J

    2017-01-01

    Cells are delineated by a lipid bilayer that physically separates the inside from the outer environment. Most polar, charged, or large molecules require proteins to reduce the energetic barrier for passage across the membrane and to achieve transport rates that are relevant for life. Here, we describe techniques to visualize the functioning of membrane transport proteins with fluorescent probes at the single-molecule level. First, we explain how to produce membrane-reconstituted transporters with fluorescent labels. Next, we detail the construction of a microfluidic flow cell to image immobilized proteoliposomes on a total internal reflection fluorescence microscope. We conclude by describing the methods that are needed to analyze fluorescence movies and obtain useful single-molecule data. © 2017 Elsevier Inc. All rights reserved.

  2. Development of a scanning microscopy by total internal reflection coupled with thermal lens spectroscopy.

    Science.gov (United States)

    Shimosaka, Takuya; Iwamoto, Kazutoshi; Izako, Masakazu; Suzuki, Asa; Uchiyama, Katsumi; Hobo, Toshiyuki

    2004-01-01

    Non-destructive measurement of a small region on a solid/liquid interface is of great importance in physical chemistry and biochemistry, especially in the research of thin films and cell membranes. Optical methods for surface analysis with high lateral resolution are suitable methods for monitoring them. We now report a new scanning optical microscopic method to which total internal reflection coupled with a thermal lens technique was introduced. Its lateral resolution was estimated both experimentally and theoretically. To experimentally estimate the resolution, the grid patterns of thin photoresist films with well-defined lateral structures were measured. The experimental resolution was about 45 microm, which was almost same as the diameter of the excitation beam at a glass/sample interface. From this result, it was verified that this new scanning microscopy ideally worked.

  3. Benchmarking of HEU Mental Annuli Critical Assemblies with Internally Reflected Graphite Cylinder

    Energy Technology Data Exchange (ETDEWEB)

    Xiaobo, Liu; Bess, John D.; Marshall, Margaret A.

    2016-09-01

    Three experimental configurations of critical assemblies, performed in 1963 at the Oak Ridge Critical Experiment Facility, which are assembled using three different diameter HEU annuli (15-9 inches, 15-7 inches and 13-7 inches) metal annuli with internally reflected graphite cylinder are evaluated and benchmarked. The experimental uncertainties which are 0.00055, 0.00055 and 0.00055 respectively, and biases to the detailed benchmark models which are -0.00179, -0.00189 and -0.00114 respectively, were determined, and the experimental benchmark keff results were obtained for both detailed and simplified model. The calculation results for both detailed and simplified models using MCNP6-1.0 and ENDF VII.1 agree well to the benchmark experimental results with a difference of less than 0.2%. These are acceptable benchmark experiments for inclusion in the ICSBEP Handbook.

  4. Maintaining a stationary laser footprint during angular scan in internal-reflection experiments.

    Science.gov (United States)

    Fontana, Eduardo; Cavalcanti, Gustavo Oliveira

    2013-11-10

    In internal-reflection metrology using prisms, the prism is usually mounted on a rotation/translation stage to enable adjusting angle and location of the laser footprint on the surface. If a visual inspection method is used to find the laser footprint, the task becomes impossible if invisible radiation in the near infrared is employed. In addition, it may be desirable to perform angular scan experiments with a stationary footprint on the surface during scans, or even to automatically probe specific points on an extended prism face for predetermined incidence angles. In this paper, a formulation is developed to determine the required translation along the prism face to allow maintaining the laser footprint stationary under a given rotation. A web-based app developed under the scope of this work demonstrates the applicability of the approach for silica, BK7 and SF2 glasses, in the wavelength range from 500 to 1500 nm and for an arbitrary geometry of the glass prism.

  5. Label free imaging of cell-substrate contacts by holographic total internal reflection microscopy.

    Science.gov (United States)

    Mandracchia, Biagio; Gennari, Oriella; Marchesano, Valentina; Paturzo, Melania; Ferraro, Pietro

    2017-09-01

    The study of cell adhesion contacts is pivotal to understand cell mechanics and interaction at substrates or chemical and physical stimuli. We designed and built a HoloTIR microscope for label-free quantitative phase imaging of total internal reflection. Here we show for the first time that HoloTIR is a good choice for label-free study of focal contacts and of cell/substrate interaction as its sensitivity is enhanced in comparison with standard TIR microscopy. Finally, the simplicity of implementation and relative low cost, due to the requirement of less optical components, make HoloTIR a reasonable alternative, or even an addition, to TIRF microscopy for mapping cell/substratum topography. As a proof of concept, we studied the formation of focal contacts of fibroblasts on three substrates with different levels of affinity for cell adhesion. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. An internally reflecting Cherenkov detector (DIRC): Properties of the fused silica radiators

    International Nuclear Information System (INIS)

    Adam, I.; Aston, D.

    1997-11-01

    The DIRC, a new type of ring-imaging Cherenkov detector that images internally reflected Cherenkov light, is being constructed as the main hadronic particle identification component of the BABAR detector at SLAC. The device makes use of 5 meter long fused silica (colloquially called quartz) bars, which serve both as the Cherenkov radiators and as light pipes for transmitting the light to an array of photo-multiplier tubes. This paper describes a program of research and development aimed at determining whether bars that meet the stringent requirements of the DIRC can be obtained from commercial sources. The results of studies of bulk absorption of fused silica, surface finish, radiation damage and bulk inhomogeneities are discussed

  7. Common-path configuration in total internal reflection digital holography microscopy.

    Science.gov (United States)

    Calabuig, Alejandro; Matrecano, Marcella; Paturzo, Melania; Ferraro, Pietro

    2014-04-15

    Total Internal Reflection Digital Holographic Microscopy (TIRDHM) is recognized to be a powerful tool for retrieving quantitative phase images of cell-substrate interfaces, adhesions, and tissue structures close to the prism surface. In this Letter, we develop an improved TIRDHM system, taking advantage of a refractive index mismatch between the prism and the sample substrate, to allow phase-shifting DH with just a single-beam interferometric configuration. Instead of the traditional off-axis method, phase-shift method is used to retrieve amplitude and phase images in coherent light and TIR modality. Essentially, the substrate-prism interface acts like a beam splitter generating a reference beam, where the phase-shift dependence on the incident angle is exploited in this common-path configuration. With the aim to demonstrate the technique's validity, some experiments are performed to establish the advantage of this compact and simple configuration, in which the reference arm in the setup is avoided.

  8. Internal quantum efficiency in yellow-amber light emitting AlGaN-InGaN-GaN heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Ngo, Thi Huong; Gil, Bernard; Valvin, Pierre [Laboratoire Charles Coulomb – UMR 5221, CNRS and University Montpellier, Case courier 074, 34095 Montpellier Cedex 5 (France); Damilano, Benjamin; Lekhal, Kaddour; De Mierry, Philippe [CRHEA-CNRS Centre de Recherche sur l' Hétéro-Epitaxie et ses Applications, Centre National de la Recherche Scientifique, rue Bernard Gregory, 06560 Valbonne (France)

    2015-09-21

    We determine the internal quantum efficiency of strain-balanced AlGaN-InGaN-GaN hetero-structures designed for yellow-amber light emission, by using a recent model based on the kinetics of the photoluminescence decay initiated by Iwata et al. [J. Appl. Phys. 117, 075701 (2015)]. Our results indicate that low temperature internal quantum efficiencies sit in the 50% range and we measure that adding an AlGaN layer increases the internal quantum efficiency from 50% up to 57% with respect to the GaN-InGaN case. More dramatic, it almost doubles from 2.5% up to 4.3% at room temperature.

  9. Analysis of thin-film polymers using attenuated total internal reflection-Raman microspectroscopy.

    Science.gov (United States)

    Tran, Willie; Tisinger, Louis G; Lavalle, Luis E; Sommer, André J

    2015-01-01

    Two methods commonly employed for molecular surface analysis and thin-film analysis of microscopic areas are attenuated total reflection infrared (ATR-IR) microspectroscopy and confocal Raman microspectroscopy. In the former method, the depth of the evanescent probe beam can be controlled by the wavelength of light, the angle of incidence, or the refractive index of the internal reflection element. Because the penetration depth is proportional to the wavelength of light, one could interrogate a smaller film thickness by moving from the mid-infrared region to the visible region employing Raman spectroscopy. The investigation of ATR Raman microspectroscopy, a largely unexplored technique available to Raman microspectroscopy, was carried out. A Renishaw inVia Raman microscope was externally modified and used in conjunction with a solid immersion lens (SIL) to perform ATR Raman experiments. Thin-film polymer samples were analyzed to explore the theoretical sampling depth for experiments conducted without the SIL, with the SIL, and with the SIL using evanescent excitation. The feasibility of micro-ATR Raman was examined by collecting ATR spectra from films whose thickness measured from 200 to 60 nm. Films of these thicknesses were present on a much thicker substrate, and features from the underlying substrate did not become visible until the thin film reached a thickness of 68 nm.

  10. PREFACE: The 5th International Symposium in Quantum Theory and Symmetries (QTS5)

    Science.gov (United States)

    Arratia, O.; Calzada, J. A.; Gómez-Cubillo, F.; Negro, J.; del Olmo, M. A.

    2008-02-01

    This volume of Journal of Physics: Conference Series contains the Proceedings of the 5th International Symposium in Quantum Theory and Symmetries (QTS5), held in Valladolid, Spain, 22-28 July 2007. This is the fifth of a series of conferences previously held in Goslar (Germany) 1999, QTS1; Cracow (Poland) 2001, QTS2; Cincinnati (USA) 2003, QTS3, and Varna (Bulgaria) 2005, QTS4. The QTS5 symposium gathered 181 participants from 39 countries working in different fields on Theoretical Physics. The spirit of the QTS conference series is to join researchers in a wide variety of topics in Theoretical Physics, as a way to make accessible recent results and the new lines of different fields. The QTS5 conference offered the following list of topics: Symmetries in String Theory, Quantum Gravity and related Symmetries in Quantum Field Theories, Conformal and Related Field Theories, Lattice and Noncommutative Theories, Gauge Theories Quantum Computing, Information and Control Foundations of Quantum Theory Quantum Optics, Coherent States, Wigner Functions Dynamical and Integrable Systems Symmetries in Condensed Matter and Statistical Physics Symmetries in Particle Physics, Nuclear, Atomic and Molecular Nonlinear Quantum Mechanics Time Asymmetric Quantum Mechanics SUSY Quantum Mechanics, PT symmetries and pseudo-Hamiltonians Mathematical Methods for Symmetries and Quantum Theories Symmetries in Chemistry Biology and other Sciences Papers accepted for publication in the present issue are based on the contributions from the participants in the QTS5 conference after a peer review process. In addition, a special issue of Journal Physics A: Mathematical and Theoretical contains contributions from plenary speakers, some participants as well as contributions from other authors whose works fit into the topics of the conference. The organization of the conference had the following pattern. In the morning there were five plenary or general sessions for all the participants, which aimed to

  11. Intradot spin-flip Andreev reflection tunneling through a ferromagnet-quantum dot-superconductor system with ac field

    International Nuclear Information System (INIS)

    Song Hongyan; Zhou Shiping

    2008-01-01

    We investigate Andreev reflection (AR) tunneling through a ferromagnet-quantum dot-superconductor (F-QD-S) system in the presence of an external ac field. The intradot spin-flip scattering in the QD is involved. Using the nonequilibrium Green function and BCS quasiparticle spectrum for superconductor, time-averaged AR conductance is formulated. The competition between the intradot spin-flip scattering and photon-assisted tunneling dominates the resonant behaviors of the time-averaged AR conductance. For weak intradot spin-flip scattering strengths, the AR conductance shows a series of equal interval resonant levels. However, the single-peak at main resonant level develops into a well-resolved double-peak resonance at a strong intradot spin-flip scattering strength. Remarkable, multiple-photon-assisted tunneling that generates photonic sideband peaks with a variable interval has been found. In addition, the AR conductance-bias voltage characteristic shows a transition between the single-peak to double-peak resonance as the ratio of the two tunneling strengths varies

  12. Unusual conversations: A reflection on the mechanics of internationally engaged public scholarship

    Directory of Open Access Journals (Sweden)

    Jonathan Damiani

    2016-09-01

    Full Text Available This article analyses the civic engagement pathways of researchers from the Asia-Pacific and the United States in an effort to see how the principles of what American  scholars consider publicly engaged research and creative practice are being enacted in research sites across the globe. The purpose of this ongoing project is to focus on finding ways of connecting American scholars with a network of higher education and research institutions that hold a commitment and passion for social responsibility and civic engagement as it impacts education, research and service for community development overseas. The narrative includes the voices and perspectives of colleagues dedicated to engaged scholarship from across the new region in which I work (the Asia-Pacific, alongside the voices of some of Imagining America’s (IA 2014 National Conference participants. These conversations serve as a critical reflection on the mechanics of doing public scholarship overseas and frame a new model of internationally engaged scholarship. Keywords: Internationally engaged public scholarship, unusual conversations

  13. Stimulus-dependent EEG activity reflects internal updating of tactile working memory in humans.

    Science.gov (United States)

    Spitzer, Bernhard; Blankenburg, Felix

    2011-05-17

    Despite recent advances in uncovering the neural signature of tactile working memory processing in animals and humans, the representation of internally modified somatosensory working memory content has not been studied so far. Here, recording EEG in human participants (n = 25) performing a modified delayed match-to-sample task allowed us to disambiguate internally driven memory processing from encoding-related delay activity. After presentation of two distinct vibrotactile frequencies to different index fingers, a visual cue indicated which of the two previous stimuli had to be maintained in working memory throughout a retention interval for subsequent frequency discrimination against a probe stimulus. During cued stimulus maintenance, α activity (8-13 Hz) over early somatosensory cortices was lateralized according to the cued tactile stimulus, even though the location of the stimuli was task irrelevant. The task-relevant memory content, in contrast, was found to be represented in right prefrontal cortex. The key finding was that the visually presented instructions triggered systematic modulations of prefrontal β-band activity (20-25 Hz), which selectively reflected the to-be-maintained frequency of the cued tactile vibration. The results expand previous evidence for parametric representations of vibrotactile frequency in the prefrontal cortex and corroborate a central role of dynamic β-band synchronization during active processing of an analog stimulus quantity in human working memory. In particular, our findings suggest that such processing supports not only sustained maintenance but also purposeful modification and updating of the task-relevant working memory contents.

  14. Simulation and Experimental Study on Anti-reflection Characteristics of Nano-patterned Si Structures for Si Quantum Dot-Based Light-Emitting Devices.

    Science.gov (United States)

    Shao, Wenyi; Lu, Peng; Li, Wei; Xu, Jun; Xu, Ling; Chen, Kunji

    2016-12-01

    Surface-textured structure is currently an interesting topic since it can efficiently reduce the optical losses in advanced optoelectronic devices via light management. In this work, we built a model in finite-difference time-domain (FDTD) solutions by setting the simulation parameters based on the morphology of the Si nanostructures and compared with the experimental results in order to study the anti-reflection behaviors of the present nano-patterned structures. It is found that the reflectance is gradually reduced by increasing the depth of Si nanostructures which is in well agreement with the experimental observations. The reflectance can be lower than 10 % in the light range from 400 to 850 nm for Si nano-patterned structures with a depth of 150 nm despite the quite low aspect ratio, which can be understood as the formation of gradually changed index layer and the scattering effect of Si nano-patterned structures. By depositing the Si quantum dots/SiO2 multilayers on nano-patterned Si substrate, the reflectance can be further suppressed and the luminescence intensity centered at 820 nm from Si quantum dots is enhanced by 6.6-fold compared with that of flat one, which can be attributed to the improved light extraction efficiency. However, the further etch time causes the reduction of luminescence intensity from Si quantum dots which may ascribe to the serious surface recombination of carriers.

  15. PREFACE: 6th International Workshop on Pseudo-Hermitian Hamiltonians in Quantum Physics

    Science.gov (United States)

    Fring, Andreas; Jones, Hugh; Znojil, Miloslav

    2008-06-01

    Attempts to understand the quantum mechanics of non-Hermitian Hamiltonian systems can be traced back to the early days, one example being Heisenberg's endeavour to formulate a consistent model involving an indefinite metric. Over the years non-Hermitian Hamiltonians whose spectra were believed to be real have appeared from time to time in the literature, for instance in the study of strong interactions at high energies via Regge models, in condensed matter physics in the context of the XXZ-spin chain, in interacting boson models in nuclear physics, in integrable quantum field theories as Toda field theories with complex coupling constants, and also very recently in a field theoretical scenario in the quantization procedure of strings on an AdS5 x S5 background. Concrete experimental realizations of these types of systems in the form of optical lattices have been proposed in 2007. In the area of mathematical physics similar non-systematic results appeared sporadically over the years. However, intensive and more systematic investigation of these types of non- Hermitian Hamiltonians with real eigenvalue spectra only began about ten years ago, when the surprising discovery was made that a large class of one-particle systems perturbed by a simple non-Hermitian potential term possesses a real energy spectrum. Since then regular international workshops devoted to this theme have taken place. This special issue is centred around the 6th International Workshop on Pseudo-Hermitian Hamiltonians in Quantum Physics held in July 2007 at City University London. All the contributions contain significant new results or alternatively provide a survey of the state of the art of the subject or a critical assessment of the present understanding of the topic and a discussion of open problems. Original contributions from non-participants were also invited. Meanwhile many interesting results have been obtained and consensus has been reached on various central conceptual issues in the

  16. Thermally-fluctuated single-flux-quantum pulse intervals reflected in input-output characteristics of a double-flux-quantum amplifier

    Science.gov (United States)

    Mizugaki, Yoshinao; Urai, Yoshiaki; Shimada, Hiroshi

    2017-07-01

    A double-flux-quantum amplifier (DFQA) is a voltage multiplier of quantum accuracy, which we have employed at the final stage of a single-flux-quantum (SFQ) digital-to-analog converter (DAC). We recently found that experimental input-output (IO) characteristics of DFQAs were always slightly different from numerical results assuming ideally-periodic SFQ pulse trains. That is, experimental IO characteristics obtained using an over-biasing method were gradually deteriorated near their maximum operation voltages. Numerical simulation including the over-biasing method at a finite temperature suggested that the difference was likely to be attributed to thermally-fluctuated intervals of input SFQ pulses.

  17. PREFACE: 7th International Conference on Quantum Theory and Symmetries (QTS7)

    Science.gov (United States)

    Burdík, Čestmír; Navrátil, Ondřej; Pošta, Severin; Schnabl, Martin; Šnobl, Libor

    2012-02-01

    The Seventh International Conference Quantum Theory and Symmetries (QTS7), organized by the Departments of Mathematics and Physics, Faculty of Nuclear Sciences and Physical Engineering at the Czech Technical University in Prague, the Bogoliubov Laboratory of Theoretical Physics of the Joint Institute for Nuclear Research and the Institute of Physics at the Academy of Sciences of the Czech Republic, belongs to a successful series of conferences which began at Goslar, Germany in 1999. More recent QTS conferences were held in Poland, Bulgaria, USA and Spain. QTS7 gathered around 300 scientists from all over the world. 136 of the plenary lectures and contributions presented at QTS7 are published in this issue of Journal of Physics: Conference Series. We acknowledge support from the Commission for co-operation with JINR Dubna and grant LA-08002 from the Ministry of Education of the Czech Republic. Čestmír Burdík Chairman Local Organizing Committee

  18. State-to-State Internal Energy Relaxation Following the Quantum-Kinetic Model in DSMC

    Science.gov (United States)

    Liechty, Derek S.

    2014-01-01

    A new model for chemical reactions, the Quantum-Kinetic (Q-K) model of Bird, has recently been introduced that does not depend on macroscopic rate equations or values of local flow field data. Subsequently, the Q-K model has been extended to include reactions involving charged species and electronic energy level transitions. Although this is a phenomenological model, it has been shown to accurately reproduce both equilibrium and non-equilibrium reaction rates. The usefulness of this model becomes clear as local flow conditions either exceed the conditions used to build previous models or when they depart from an equilibrium distribution. Presently, the applicability of the relaxation technique is investigated for the vibrational internal energy mode. The Forced Harmonic Oscillator (FHO) theory for vibrational energy level transitions is combined with the Q-K energy level transition model to accurately reproduce energy level transitions at a reduced computational cost compared to the older FHO models.

  19. Particles and nuclei, letters; Proceedings of the international workshop 'Quantum Physics and Communication'

    International Nuclear Information System (INIS)

    Ivanov, V.V.

    2003-01-01

    The present collection of letters from JINR, Dubna, contains ten separate records on the microscopic entropy and nonlocality, conditional density matrix: systems and subsystems in quantum mechanics, physics of quantum computation, flipping qubits, quantum zeno effect for N-level Friedrichs model, universal hybrid quantum processors, formation of the SU(3)-polarization states in atom-quantum electromagnetic field system under condition of the Bose-Einstein condensate existence, periodical sequences (trajectories) of outcomes of atomic state measurement on exit from the micromaser cavity, an algebraic method to solve the Tavis-Cummings problem, quantum teleportation of nuclear matter and its investigation

  20. Transmittance and reflectance formulations: a typical isomorphism between the rectangular potential-barrier in quantum mechanics and the dielectric slab in electromagnetic-optics

    Science.gov (United States)

    Meziane, Belkacem

    2018-03-01

    The main intent of this paper is to demonstrate that the theoretical formulations of the reflectance and transmittance characteristics of an initially free quantum particle, heading towards some restricted region of space, inside which it undergoes the effect of an electric-potential-barrier, are isomorphic to those of an incident plane- and linearly-polarized electromagnetic wave, which propagates towards and through a homogeneous dielectric slab.

  1. PREFACE: The 5th International Symposium on Quantum Theory and Symmetries (QTS5)

    Science.gov (United States)

    Gadella, M.; Izquierdo, J. M.; Kuru, S.; Negro, J.; del Olmo, M. A.

    2008-08-01

    This special issue of Journal of Physics A: Mathematical and Theoretical appears on the occasion of the 5th International Symposium on Quantum Theory and Symmetries (QTS5), held in Valladolid, Spain, from 22-28 July 2007. This is the fith in a series of conferences previously held in Goslar (Germany) 1999, QTS1; Cracow (Poland) 2001, QTS2; Cincinnati (USA) 2003, QTS3; and Varna (Bulgaria) 2005, QTS4. The QTS5 symposium gathered 181 participants from 39 countries working in different fields of theoretical physics. The spirit of the QTS conference series is to join researchers in a wide variety of topics in theoretical physics, as a way of making accessible recent results and the new lines of different fields. This is based on the feeling that it is good for a physicist to have a general overview as well as expertise in his/her own field. There are many other conferences devoted to specific topics, which are of interest to gain deeper insight in many technical aspects and that are quite suitable for discussions due to their small size. However, we believe that general conferences like this are interesting and worth keeping. We like the talks, in both plenary and parallel sessions, which are devoted to specific topics, to be prepared so as to be accessible to any researcher in any branch of theoretical physics. We think that this objective is compatible with rigour and high standards. As is well known, similar methods and techniques can be useful for many problems in different fields. We hope that this has been appreciated during the sessions of the QTS5 conference. The QTS5 conference offered the following list of topics: 1. Symmetries in string theory, quantum gravity and related topics 2. Symmetries in quantum field theories, conformal and related field theories, lattice and noncommutative theories, gauge theories 3.Quantum computing, information and control 4. Foundations of quantum theory 5. Quantum optics, coherent states, Wigner functions 6. Dynamical and

  2. Quantifying the Assembly of Multicomponent Molecular Machines by Single-Molecule Total Internal Reflection Fluorescence Microscopy.

    Science.gov (United States)

    Boehm, E M; Subramanyam, S; Ghoneim, M; Washington, M Todd; Spies, M

    2016-01-01

    Large, dynamic macromolecular complexes play essential roles in many cellular processes. Knowing how the components of these complexes associate with one another and undergo structural rearrangements is critical to understanding how they function. Single-molecule total internal reflection fluorescence (TIRF) microscopy is a powerful approach for addressing these fundamental issues. In this article, we first discuss single-molecule TIRF microscopes and strategies to immobilize and fluorescently label macromolecules. We then review the use of single-molecule TIRF microscopy to study the formation of binary macromolecular complexes using one-color imaging and inhibitors. We conclude with a discussion of the use of TIRF microscopy to examine the formation of higher-order (i.e., ternary) complexes using multicolor setups. The focus throughout this article is on experimental design, controls, data acquisition, and data analysis. We hope that single-molecule TIRF microscopy, which has largely been the province of specialists, will soon become as common in the tool box of biophysicists and biochemists as structural approaches have become today. © 2016 Elsevier Inc. All rights reserved.

  3. A total internal reflection-fluorescence correlation spectroscopy setup with pulsed diode laser excitation.

    Science.gov (United States)

    Weger, Lukas; Hoffmann-Jacobsen, Kerstin

    2017-09-01

    Fluorescence correlation spectroscopy (FCS) measures fluctuations in a (sub-)femtoliter volume to analyze the diffusive behavior of fluorescent particles. This highly sensitive method has proven to be useful for the analysis of dynamic biological systems as well as in chemistry, physics, and material sciences. It is routinely performed with commercial fluorescence microscopes, which provide a confined observation volume by the confocal technique. The evanescent wave of total internal reflectance (TIR) is used in home-built systems to permit a surface sensitive FCS analysis. We present a combined confocal and TIR-FCS setup which uses economic low-power pulsed diode lasers for excitation. Excitation and detection are coupled to time-correlated photon counting hardware. This allows simultaneous fluorescence lifetime and FCS measurements in a surface-sensitive mode. Moreover, the setup supports fluorescence lifetime correlation spectroscopy at surfaces. The excitation can be easily switched between TIR and epi-illumination to compare the surface properties with those in liquid bulk. The capabilities of the presented setup are demonstrated by measuring the diffusion coefficients of a free dye molecule, a labeled polyethylene glycol, and a fluorescent nanoparticle in confocal as well as in TIR-FCS.

  4. Extending Whole Slide Imaging: Color Darkfield Internal Reflection Illumination (DIRI for Biological Applications.

    Directory of Open Access Journals (Sweden)

    Yoshihiro Kawano

    Full Text Available Whole slide imaging (WSI is a useful tool for multi-modal imaging, and in our work, we have often combined WSI with darkfield microscopy. However, traditional darkfield microscopy cannot use a single condenser to support high- and low-numerical-aperture objectives, which limits the modality of WSI. To overcome this limitation, we previously developed a darkfield internal reflection illumination (DIRI microscope using white light-emitting diodes (LEDs. Although the developed DIRI is useful for biological applications, substantial problems remain to be resolved. In this study, we propose a novel illumination technique called color DIRI. The use of three-color LEDs dramatically improves the capability of the system, such that color DIRI (1 enables optimization of the illumination color; (2 can be combined with an oil objective lens; (3 can produce fluorescence excitation illumination; (4 can adjust the wavelength of light to avoid cell damage or reactions; and (5 can be used as a photostimulator. These results clearly illustrate that the proposed color DIRI can significantly extend WSI modalities for biological applications.

  5. Frustrated total internal reflection in organic light-emitting diodes employing sphere cavity embedded in polystyrene

    International Nuclear Information System (INIS)

    Zhu, Peifen

    2016-01-01

    The light extraction efficiency of top-emitting organic light-emitting diodes (OLEDs) is numerically investigated employing the finite-difference time-domain method. The periodic nanostructures formed by embedding the sphere arrays in polystyrene (PS) are placed on top of OLED to frustrate the total internal reflection at the interface between OLED and free space. These nanostructures serve as an intermediate medium to extract the light out of OLED devices. Efficiently coupling both evanescent waves and propagation waves into spheres and subsequently extracting these light waves out of the sphere is key to achieving high extraction efficiency. By tuning the thickness of PS layer, both of the in-coupling efficiency and out-coupling efficiency are optimized for achieving high light extraction efficiency. Thicker PS layer results in higher in-coupling efficiency in sphere while the thinner PS layer leads to higher out-coupling efficiency. Thus the maximum light extraction is a trade-off between the in-coupling efficiency and out-coupling efficiency. The study shows that light extraction efficiency of 89% can be achieved by embedding 0.90 μm TiO 2 sphere in 0.30 μm PS layer with optimized in-coupling efficiency, out-coupling efficiency and cavity effect. (paper)

  6. Extraction of light trapped due to total internal reflection using porous high refractive index nanoparticle films.

    Science.gov (United States)

    Mao, Peng; Sun, Fangfang; Yao, Hanchao; Chen, Jing; Zhao, Bo; Xie, Bo; Han, Min; Wang, Guanghou

    2014-07-21

    TiO₂ nanoparticle layers composed of columnar TiO₂ nanoparticle piles separated with nanoscale pores were fabricated on the bottom surface of the hemispherical glass prism by performing gas phase cluster beam deposition at glancing incidence. The porosity as well as the refractive index of the nanoparticle layer was precisely tuned by the incident angle. Effective extraction of the light trapped in the substrate due to total internal reflection with the TiO₂ nanoparticle layers was demonstrated and the extraction efficiency was found to increase with the porosity. An enhanced Rayleigh scattering mechanism, which results from the columnar aggregation of the nanoparticles as well as the strong contrast in the refractive index between pores and TiO₂ nanoparticles in the nanoporous structures, was proposed. The porous TiO₂ nanoparticle coatings were fabricated on the surface of GaN LEDs to enhance their light output. A nearly 92% PL enhancement as well as a 30% EL enhancement was observed. For LED applications, the enhanced light extraction with the TiO₂ nanoparticle porous layers can be a supplement to the microscale texturing process for light extraction enhancement.

  7. New light on ion channel imaging by total internal reflection fluorescence (TIRF) microscopy.

    Science.gov (United States)

    Yamamura, Hisao; Suzuki, Yoshiaki; Imaizumi, Yuji

    2015-05-01

    Ion channels play pivotal roles in a wide variety of cellular functions; therefore, their physiological characteristics, pharmacological responses, and molecular structures have been extensively investigated. However, the mobility of an ion channel itself in the cell membrane has not been examined in as much detail. A total internal reflection fluorescence (TIRF) microscope allows fluorophores to be imaged in a restricted region within an evanescent field of less than 200 nm from the interface of the coverslip and plasma membrane in living cells. Thus the TIRF microscope is useful for selectively visualizing the plasmalemmal surface and subplasmalemmal zone. In this review, we focused on a single-molecule analysis of the dynamic movement of ion channels in the plasma membrane using TIRF microscopy. We also described two single-molecule imaging techniques under TIRF microscopy: fluorescence resonance energy transfer (FRET) for the identification of molecules that interact with ion channels, and subunit counting for the determination of subunit stoichiometry in a functional channel. TIRF imaging can also be used to analyze spatiotemporal Ca(2+) events in the subplasmalemma. Single-molecule analyses of ion channels and localized Ca(2+) signals based on TIRF imaging provide beneficial pharmacological and physiological information concerning the functions of ion channels. Copyright © 2015 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  8. Gold nanoparticle-polydimethylsiloxane films reflect light internally by optical diffraction and Mie scattering

    Science.gov (United States)

    Dunklin, Jeremy R.; Forcherio, Gregory T.; Roper, D. Keith

    2015-08-01

    Optical properties of polymer films embedded with plasmonic nanoparticles (NPs) are important in many implementations. In this work, optical extinction by polydimethylsiloxane (PDMS) films containing gold (Au) NPs was enhanced at resonance compared to AuNPs in suspensions, Beer-Lambert law, or Mie theory by internal reflection due to optical diffraction in 16 nm AuNP-PDMS films and Mie scattering in 76 nm AuNP-PDMS films. Resonant extinction per AuNP for 16 nm AuNPs with negligible resonant Mie scattering was enhanced up to 1.5-fold at interparticle separation (i.e., Wigner-Seitz radii) comparable to incident wavelength. It was attributable to diffraction through apertures formed by overlapping electric fields of adjacent, resonantly excited AuNPs at Wigner-Seitz radii equal to or less than incident wavelengths. Resonant extinction per AuNP for strongly Mie scattering 76 nm AuNPs was enhanced up to 1.3-fold at Wigner-Seitz radii four or more times greater than incident wavelength. Enhanced light trapping from diffraction and/or scattering is relevant to optoelectronic, biomedical, and catalytic activity of substrates embedded with NPs.

  9. Tunable Wide-Angle Tunneling in Graphene-Assisted Frustrated Total Internal Reflection

    Science.gov (United States)

    Tran, Thang Q.; Lee, Sangjun; Heo, Hyungjun; Kim, Sangin

    2016-01-01

    Electrically tunable permittivity of graphene provides an excellent tool in photonic device design. Many previous works on graphene-based photonic devices relied on variable absorption in graphene, which is naturally small in the optical region, and resonant structures to enhance it. Here we proposed a novel scheme to control evanescent coupling strength by inserting two graphene layers to a frustrated total internal reflection (FTIR) configuration. The resulting structure behaves in a drastically different way from the original FTIR: optical transmission though the structure can be electrically controlled from ~10-5 to ~1 with little dependency on angle of incidence. This unique feature stems from the fact that the permittivity of doped graphene can be close to zero at a certain photon energy. The electrical controllability of evanescent coupling strength can enable novel design of optical devices. As a proof-of-concept, we designed a waveguide-type optical modulator of a novel operation principle: transmission modulation depends on the electrically controlled existence of a guided-mode of the waveguide, not the variation of the ohmic loss of graphene, resulting in a low insertion loss and a small device footprint.

  10. Attenuated total internal reflection Fourier transform infrared spectroscopy: a quantitative approach for kidney stone analysis.

    Science.gov (United States)

    Gulley-Stahl, Heather J; Haas, Jennifer A; Schmidt, Katherine A; Evan, Andrew P; Sommer, André J

    2009-07-01

    The impact of kidney stone disease is significant worldwide, yet methods for quantifying stone components remain limited. A new approach requiring minimal sample preparation for the quantitative analysis of kidney stone components has been investigated utilizing attenuated total internal reflection Fourier transform infrared spectroscopy (ATR-FT-IR). Calcium oxalate monohydrate (COM) and hydroxylapatite (HAP), two of the most common constituents of urinary stones, were used for quantitative analysis. Calibration curves were constructed using integrated band intensities of four infrared absorptions versus concentration (weight %). The correlation coefficients of the calibration curves range from 0.997 to 0.93. The limits of detection range from 0.07 +/- 0.02% COM/HAP where COM is the analyte and HAP is the matrix, to 0.26 +/- 0.07% HAP/COM where HAP is the analyte and COM is the matrix. This study shows that linear calibration curves can be generated for the quantitative analysis of stone mixtures provided the system is well understood especially with respect to particle size.

  11. Proceedings of quantum field theory, quantum mechanics, and quantum optics

    International Nuclear Information System (INIS)

    Dodonov, V.V.; Man; ko, V.I.

    1991-01-01

    This book contains papers presented at the XVIII International Colloquium on Group Theoretical Methods in Physics held in Moscow on June 4-9, 1990. Topics covered include; applications of algebraic methods in quantum field theory, quantum mechanics, quantum optics, spectrum generating groups, quantum algebras, symmetries of equations, quantum physics, coherent states, group representations and space groups

  12. PREFACE: 5th International Workshop DICE2010: Space-Time-Matter - Current Issues in Quantum Mechanics and Beyond

    Science.gov (United States)

    Diósi, Lajos; Elze, Hans-Thomas; Fronzoni, Leone; Halliwell, Jonathan; Prati, Enrico; Vitiello, Giuseppe; Yearsley, James

    2011-07-01

    These proceedings present the Invited Lectures and Contributed Papers of the Fifth International Workshop on Decoherence, Information, Complexity and Entropy - DICE 2010, held at Castello Pasquini, Castiglioncello (Tuscany), 13-17 September 2010. These proceedings are intended to document the stimulating exchange of ideas at this conference for both the interested public and the wider scientific community, as well as for the participants. The number of participants attending this series of meetings has been growing steadily, which reflects its increasing attraction. Our intention to bring together leading researchers, advanced students, and renowned scholars from various areas in order to stimulate new ideas and their exchange across the borders of specialization seems to bear fruit. In this way, the series of meetings has continued successfully from the beginning with DICE 2002 [1], followed by DICE 2004 [2], DICE 2006 [3], and DICE 2008 [4], uniting more than 100 participants representing almost 30 countries worldwide. It has been a great honour and inspiration to have Professor Luc Montagnier (Nobel Prize for Medicine 2008) from the World Foundation for AIDS Research and Prevention with us, who presented the lecture DNA waves and water (included in this volume). The discussions took place under the wider theme Space-Time-Matter - current issues in quantum mechanics and beyond in the very pleasant and inspiring atmosphere of Castello Pasquini, which - with its beautiful surroundings, overlooking the Tuscany coast - hosted the conference very successfully for the second time. The five-day program was grouped according to the following topics: Gravity and Quantum Mechanics Quantum Coherent Processes in Biology / Many-Body Systems From Quantum Foundations to Particle Physics The Deep Structure of Spacetime Quantum - Relativity - Cosmology A Public Roundtable Discussion formed an integral part of the program under the theme Sull' Onda Della Coerenza" - le nuove

  13. Meaning, Internalization, and Externalization: Toward a Fuller Understanding of the Process of Reflection and Its Role in the Construction of the Self

    Science.gov (United States)

    Le Cornu, Alison

    2009-01-01

    The study of the process of reflection has a dignified history. However, few have linked reflection to the development of the self in such a way that the form of reflection is understood to influence the resultant type of self. This article explores the process of reflection using a framework of meaning making, internalization, and externalization…

  14. How Is Buddhism Relevant to Career Counseling in an International High School in Hong Kong? A Counsellor's Reflection

    Science.gov (United States)

    Ng, Vinci; Yuen, Mantak

    2015-01-01

    This paper reflects upon the relevance of Buddhism to counselling in general and to career counseling in particular by discussing a program implemented at an international school in Hong Kong. The authors provide an analysis of the pertinent literature related to relevant concepts within Buddhism. This topic has not yet been adequately researched…

  15. Reflections on International Comparative Education Survey Methodology: A Case Study of the European Survey on Language Competences

    Science.gov (United States)

    Ashton, Karen

    2016-01-01

    This paper reflects on the methodology used in international comparative education surveys by conducting a systematic review of the European Survey on Language Competences (ESLC). The ESLC was administered from February to March 2011, with final results released in June 2012. The survey tested approximately 55,000 students across 14 European…

  16. Heterogeneous amylin fibril growth mechanisms imaged by total internal reflection fluorescence microscopy.

    Science.gov (United States)

    Patil, Sharadrao M; Mehta, Andrew; Jha, Suman; Alexandrescu, Andrei T

    2011-04-12

    Total internal reflection fluorescence microscopy has been used to visualize the fibrillization of amylin, a hormone which in aggregated forms plays a role in type 2 diabetes pathology. Data were obtained at acidic pH where fibrillization is hindered by the charging of histidine 18 and at slightly basic pH where the loss of charge on the histidine promotes aggregation. The experiments show three types of aggregate growth processes. In the earliest steps globular seeds are formed with some expanding radially during the course of the reaction. The dimensions of the globular seeds as well as their staining with the amyloid-specific dye thioflavin T indicate that they are plaques of short fibrils. The next species observed are fibrils that invariably grow from large globular seeds or smaller punctate granules. Fibril elongation appears to be unidirectional, although in some cases multiple fibrils radiate from a single seed or granule. After fibrils are formed, some show an increase in fluorescence intensity that we attribute to the growth of new fibrils alongside those previously formed. All three aggregation processes are suggestive of secondary (heterogeneous) nucleation mechanisms in which nucleation occurs on preformed fibrils. Consistently, electron micrographs show changes in fibril morphology well after fibrils are first formed, and the growth processes observed by fluorescence microscopy occur after the corresponding solution reactions have reached an initial apparent plateau. Taken together, the results highlight the importance of secondary nucleation in the fibrillization of amylin, as this could provide a pathway to continue fibril growth once an initial population of fibrils is established.

  17. Measurements of long-range interactions between protein-functionalized surfaces by total internal reflection microscopy.

    Science.gov (United States)

    Wang, Zhaohui; Gong, Xiangjun; Ngai, To

    2015-03-17

    Understanding the interaction between protein-functionalized surfaces is an important subject in a variety of protein-related processes, ranging from coatings for biomedical implants to targeted drug carriers and biosensors. In this work, utilizing a total internal reflection microscope (TIRM), we have directly measured the interactions between micron-sized particles decorated with three types of common proteins concanavalin A (ConA), bovine serum albumin (BSA), lysozyme (LYZ), and glass surface coated with soy proteins (SP). Our results show that the protein adsorption greatly affects the charge property of the surfaces, and the interactions between those protein-functionalized surfaces depend on solution pH values. At pH 7.5-10.0, all these three protein-functionalized particles are highly negatively charged, and they move freely above the negatively charged SP-functionalized surface. The net interaction between protein-functionalized surfaces captured by TIRM was found as a long-range, nonspecific double-layer repulsion. When pH was decreased to 5.0, both protein-functionalized surfaces became neutral and double-layer repulsion was greatly reduced, resulting in adhesion of all three protein-functionalized particles to the SP-functionalized surface due to the hydrophobic attraction. The situation is very different at pH = 4.0: BSA-decorated particles, which are highly charged, can move freely above the SP-functionalized surfaces, while ConA- and LYZ-decorated particles can only move restrictively in a limited range. Our results quantify these nonspecific kT-scale interactions between protein-functionalized surfaces, which will enable the design of surfaces for use in biomedical applications and study of biomolecular interactions.

  18. Attenuated total internal reflection infrared microscopy of multilayer plastic packaging foils.

    Science.gov (United States)

    van Dalen, Gerard; Heussen, Patricia C M; den Adel, Ruud; Hoeve, Robert B J

    2007-06-01

    Multilayer plastic foils are important packaging materials that are used to extend the shelf life of food products and drinks. Fourier transform infrared (FT-IR) spectroscopic imaging using attenuated total internal reflection (ATR) can be used for the identification and localization of different layers in multilayer foils. A new type of ATR crystal was used in combination with a linear array detector through which large sample areas (400 x 400 microm(2)) could be imaged with a pixel size of 1.6 microm. The method was tested on laminated plastic packing materials containing 5 to 12 layers. The results of the identification of the different materials using ATR-FT-IR were compared with differential scanning calorimetry (DSC) and the layer thickness of the individual layers measured by ATR-FT-IR was compared with polarized light microscopy (LM) and scanning electron microscopy (SEM). It has been demonstrated that individual layers with a thickness of about 3 microm could be identified in multilayer foils with a total thickness ranging from 100 to 150 microm. The results show a spatial resolution of about 4 microm (measured at wavenumbers ranging from 1000 to 1730 cm(-1)), which is about a factor of two better than can be obtained using transmission FT-IR imaging. An additional advantage of ATR is the ease of sample preparation. A good correspondence was found between visible and FT-IR images. The results of ATR-FT-IR imaging were in agreement with those obtained by LM, SEM, and DSC. ATR-FT-IR is superior to the combination of these techniques because it delivers both spatial and chemical information.

  19. Temperature-dependent modulated reflectance of InAs/InGaAs/GaAs quantum dots-in-a-well infrared photodetectors

    Energy Technology Data Exchange (ETDEWEB)

    Nedzinskas, R., E-mail: ramunas@pfi.lt; Čechavičius, B.; Rimkus, A.; Pozingytė, E.; Kavaliauskas, J.; Valušis, G. [Semiconductor Physics Institute, Center for Physical Sciences and Technology, A. Goštauto 11, LT-01108 Vilnius (Lithuania); Li, L. H.; Linfield, E. H. [School of Electronic and Electrical Engineering, University of Leeds, Leeds LS2 9JT (United Kingdom)

    2015-04-14

    We present a photoreflectance (PR) study of multi-layer InAs quantum dot (QD) photodetector structures, incorporating InGaAs overgrown layers and positioned asymmetrically within GaAs/AlAs quantum wells (QWs). The influence of the back-surface reflections on the QD PR spectra is explained and a temperature-dependent photomodulation mechanism is discussed. The optical interband transitions originating from the QD/QW ground- and excited-states are revealed and their temperature behaviour in the range of 3–300 K is established. In particular, we estimated the activation energy (∼320 meV) of exciton thermal escape from QD to QW bound-states at high temperatures. Furthermore, from the obtained Varshni parameters, a strain-driven partial decomposition of the InGaAs cap layer is determined.

  20. Giersch International Symposion 2016 : Week 1 : Experimental Search for Quantum Gravity

    CERN Document Server

    Experimental Search for Quantum Gravity

    2018-01-01

    This book summarizes recent developments in the research area of quantum gravity phenomenology. A series of short and nontechnical essays lays out the prospects of various experimental possibilities and their current status. Finding observational evidence for the quantization of space-time was long thought impossible. In the last decade however, new experimental design and technological advances have changed the research landscape and opened new perspectives on quantum gravity. Formerly dominated by purely theoretical constructions, quantum gravity now has a lively phenomenology to offer. From high precision measurements using macroscopic quantum oscillators to new analysis methods of the cosmic microwave background, no stone is being left unturned in the experimental search for quantum gravity. This book sheds new light on the connection of astroparticle physics with the quantum gravity problem. Gravitational waves and their detection are covered. It illustrates findings from the interconnection between gene...

  1. Communication Education and International Audiences: Reflections on Instructional Challenges and Pedagogical Strategy

    Science.gov (United States)

    Campbell, Heather; Strawser, Michael G.; George, Stephen

    2016-01-01

    As the movement toward international education continues, institutions must be proficient when reaching and teaching international students. Instructors should engage unique learning styles, address individual student needs, and take part in additional training to effectively teach international student learners. These instructional imperatives…

  2. Do people ruminate because they haven't digested their goals? The relations of rumination and reflection to goal internalization and ambivalence

    DEFF Research Database (Denmark)

    Thomsen, Dorthe Kirkegaard; Tønnesvang, Jan; Schnieber, Anette

    2011-01-01

    , and internalization of self-regulation and goals. In Study 1, rumination was related to less internalized self-regulation, whereas reflection was related to more internalized self-regulation. In Study 2, rumination was related to less internalized self-regulation and goals as well as to more avoidance- and extrinsic...

  3. Internal versus external service quality: reflections of employees and customers in the mirror

    Directory of Open Access Journals (Sweden)

    Emir Ganic

    2017-09-01

    perceptions of the quality of university services. Perceptions of internal service quality are also positively related to students’ perceptions of reliability, responsiveness and quality assurance. Conclusions: The perceptions of internal service quality by faculty members are positively related to students’ perceptions of quality. Comparing the levels of internal and external service quality will help managers define priorities for allocating resources to improve quality.

  4. High Refractive Index Silicone Gels for Simultaneous Total Internal Reflection Fluorescence and Traction Force Microscopy of Adherent Cells

    Science.gov (United States)

    Besser, Achim; Sundd, Prithu; Ley, Klaus; Danuser, Gaudenz; Ginsberg, Mark H.; Groisman, Alex

    2011-01-01

    Substrate rigidity profoundly impacts cellular behaviors such as migration, gene expression, and cell fate. Total Internal Reflection Fluorescence (TIRF) microscopy enables selective visualization of the dynamics of substrate adhesions, vesicle trafficking, and biochemical signaling at the cell-substrate interface. Here we apply high-refractive-index silicone gels to perform TIRF microscopy on substrates with a wide range of physiological elastic moduli and simultaneously measure traction forces exerted by cells on the substrate. PMID:21961031

  5. All-optical microscope autofocus based on an electrically tunable lens and a totally internally reflected IR laser.

    Science.gov (United States)

    Bathe-Peters, M; Annibale, P; Lohse, M J

    2018-02-05

    Microscopic imaging at high spatial-temporal resolution over long time scales (minutes to hours) requires rapid and precise stabilization of the microscope focus. Conventional and commercial autofocus systems are largely based on piezoelectric stages or mechanical objective actuators. Objective to sample distance is either measured by image analysis approaches or by hardware modules measuring the intensity of reflected infrared light. We propose here a truly all-optical microscope autofocus taking advantage of an electrically tunable lens and a totally internally reflected infrared probe beam. We implement a feedback-loop based on the lateral position of a totally internally reflected infrared laser on a quadrant photodetector, as an indicator of the relative defocus. We show here how to treat the combined contributions due to mechanical defocus and deformation of the tunable lens. As a result, the sample can be kept in focus without any mechanical movement, at rates up to hundreds of Hertz. The device requires only reflective optics and can be implemented at a fraction of the cost required for a comparable piezo-based actuator.

  6. A plastic total internal reflection-based photoluminescence device for enzymatic biosensors

    Science.gov (United States)

    Thakkar, Ishan G.

    Growing concerns for quality of water, food and beverages in developing and developed countries drive sizeable markets for mass-producible, low cost devices that can measure the concentration of contaminant chemicals in water, food, and beverages rapidly and accurately. Several fiber-optic enzymatic biosensors have been reported for these applications, but they exhibit very strong presence of scattered excitation light in the signal for sensing, requiring expensive thin-film filters, and their non-planar structure makes them challenging to mass-produce. Several other planar optical waveguide-based biosensors prove to be relatively costly and more fragile due to constituent materials and the techniques involved in their fabrication. So, a plastic total internal reflection (TIR)-based low cost, low scatter, field-portable device for enzymatic biosensors is fabricated and demonstrated. The design concept of the TIR-based photoluminescent enzymatic biosensor device is explained. An analysis of economical materials with appropriate optical and chemical properties is presented. PMMA and PDMS are found to be appropriate due to their high chemical resistance, low cost, high optical transmittance and low auto-fluorescence. The techniques and procedures used for device fabrication are discussed. The device incorporated a PMMA-based optical waveguide core and PDMS-based fluid cell with simple multi-mode fiber-optics using cost-effective fabrication techniques like molding and surface modification. Several techniques of robustly depositing photoluminescent dyes on PMMA core surface are discussed. A pH-sensitive fluorescent dye, fluoresceinamine, and an O2-sensitive phosphorescent dye, Ru(dpp) both are successfully deposited using Si-adhesive gel-based as well as HydroThane-based deposition methods. Two different types of pH-sensors using two different techniques of depositing fluoresceinamine are demonstrated. Also, the effect of concentration of fluoresceinamine-dye molecules

  7. Troubling Metaphors and International Student Adjustment: Reflections from a Transnational Place

    Science.gov (United States)

    Starr-Glass, David

    2017-01-01

    On many campuses, offices of International Student Affairs address the perceived needs of international students. However, a number of underlying assumptions and persistent metaphors shape these efforts and influence their outcomes. All students are uniquely different and face equally different challenges in adjusting to higher education. Labeling…

  8. Living and Learning Internationally for a Viable Future: Reflecting on UNESCO CONFINTEA VI

    Science.gov (United States)

    Henschke, John A.

    2012-01-01

    International travel has the potential to expand one's learning horizons exponentially, especially with the abundantly enriching experiences of adult, continuing, and lifelong learning conferences. CONFINTEA VI (The Sixth World International Conference in Adult Education) sponsored by the United Nations Educational, Scientific, and Cultural…

  9. Education for International Mindedness: Life History Reflections on Schooling and the Shaping of a Cosmopolitan Outlook

    Science.gov (United States)

    Wright, Katie; Buchanan, Emma

    2017-01-01

    The development of "international mindedness" is an established aim of international education and has recently gained prominence in national school systems. Despite its increasing salience, it remains an ambiguous construct and an understudied aspect of schooling. It is implicated in globalized educational markets and attempts to…

  10. Reflections and Experiences of Student Paramedics Undertaking International Work-Integrated Learning Placements

    Science.gov (United States)

    Simpson, Paul; Thyer, Liz; Van Nugteren, Ben; Mitchell, Glen; Werner, Sarah

    2016-01-01

    International work-integrated learning (WIL) is increasingly common in health-related programs in Australian universities. Paramedicine programs are beginning to explore international WIL in line with the globalization of paramedicine as a profession and the national higher education emphasis on outward bound learning experiences. Using…

  11. Interns reflect: the effect of formative assessment with feedback during pre-internship

    Directory of Open Access Journals (Sweden)

    McKenzie S

    2017-01-01

    Full Text Available Susan McKenzie,1 Annette Burgess,2 Craig Mellis1 1Central Clinical School, 2Education Office, Sydney Medical School, The University of Sydney, Sydney, NSW, Australia Background: It is widely known that the opportunity for medical students to be observed and to receive feedback on their procedural skills performance is variable in the senior years. To address this problem, we provided our Pre-Intern (PrInt students with “one-to-one” formative feedback on their ability to perform urethral catheterization (U/C and hypothesized that their future practice of U/C as interns would benefit. This study sought to evaluate the performance and practice of interns in U/C 4–5 months after having received feedback on their performance of U/C as PrInt students.Methods: Between 2013 and 2014, two cohorts of interns, (total n=66 who had received recent formative feedback on their U/C performance as PrInt students at Central Clinical School, were invited to complete an anonymous survey. The survey contained nine closed unvalidated questions and one open-ended question, designed to allow interns to report on their current practice of U/C.Results: Forty-one out of 66 interns (62% completed the survey. Thirty-five out of 41 respondents (85% reported that the assessment with feedback during their PrInt term was beneficial to their practice. Thirty of 41 (73% reported being confident to perform U/C independently. Eleven out of 41 respondents (27% reported that they had received additional training at intern orientation. Nine of the 11 interns (82% reported that they had a small, but a significant, increase in confidence to perform U/C when compared with the 30 of the 41 respondents (73% who had not (p=0.03.Conclusion: Our results substantiate our hypothesis that further education by assessment with feedback in U/C during PrInt was of benefit to interns’ performance. Additional educational reinforcement in U/C during intern orientation further improved intern

  12. Reflections on Teaching Research Ethics in Education for International Postgraduate Students in the UK

    Science.gov (United States)

    Smith, Jan

    2016-01-01

    Research ethics in education is a challenging topic to teach and to learn. As the staff and student body in UK higher education and elsewhere diversifies, the challenges increase as shared reference points diminish. My teaching reflections focus on a key tension explored in this article: how the imperative of internationalising the curriculum…

  13. Comparative Education and Research Capacity Building: Reflections on International Transfer and the Significance of Context

    Directory of Open Access Journals (Sweden)

    Michael Crossley

    2012-04-01

    Full Text Available Recent years have seen a resurgence of interest in comparative and international education, along with a fundamental reconceptualisation of this distinctive multidisciplinary field of study. The nature and significance of these developments are explored with particular reference to their implications for broader research capacity building initiatives worldwide. In doing so, a critique of the international transfer of globally dominant research modalities and strategies is presented--along with arguments for increased attention to context sensitivity in both international development cooperation and educational research in general. Illustrative examples that support these arguments are drawn from the author's own research, from an analysis of emergent educational policy debates in the UK, and from related studies being carried out in Malaysia. In concluding, the strategic role of comparative research traditions and perspectives in a rapidly globalizing world is highlighted, while supporting the promotion of new initiative and research centres for comparative and international education.

  14. Reflections between CSR and international human rights in EU initiatives for a competitive inclusive society

    DEFF Research Database (Denmark)

    Buhmann, Karin

    : The paper aims to contribute to our understanding of whether a shift is taking place in societal attitudes towards a perception that corporations have duties based on international law. This is assessed on the basis of EU initiatives on inclusiveness and responsible competitiveness, particularly...... the EU Multistakeholder Forum and the Lisbon Strategy, with a particular focus on goals or views related to the human rights of non-discrimination and rights to work, education and vocational training, and network governance in (soft) law creation. It is found that despite obvious links, international...... law does not serve as a clear source of inclusiveness or responsible competitiveness. It is also found that the initiatives assessed do not indicate a shift at EU institutional level towards a perception that business holds duties under international law. International law seems at the most to be seen...

  15. Troubling Metaphors and International Student Adjustment: Reflections from a Transnational Place

    OpenAIRE

    David Starr-Glass

    2017-01-01

    On many campuses, offices of International Student Affairs address the perceived needs of international students. However, a number of underlying assumptions and persistent metaphors shape these efforts and influence their outcomes. All students are uniquely different and face equally different challenges in adjusting to higher education. Labeling students “international” may make institutional sense, but it can potentially hinder their transition, adjustment, and ultimate success. Applying r...

  16. International Conference on Quantum Mathematical Physics : a Bridge between Mathematics and Physics

    CERN Document Server

    Kleiner, Johannes; Röken, Christian; Tolksdorf, Jürgen

    2016-01-01

    Quantum physics has been highly successful for more than 90 years. Nevertheless, a rigorous construction of interacting quantum field theory is still missing. Moreover, it is still unclear how to combine quantum physics and general relativity in a unified physical theory. Attacking these challenging problems of contemporary physics requires highly advanced mathematical methods as well as radically new physical concepts. This book presents different physical ideas and mathematical approaches in this direction. It contains a carefully selected cross-section of lectures which took place in autumn 2014 at the sixth conference ``Quantum Mathematical Physics - A Bridge between Mathematics and Physics'' in Regensburg, Germany. In the tradition of the other proceedings covering this series of conferences, a special feature of this book is the exposition of a wide variety of approaches, with the intention to facilitate a comparison. The book is mainly addressed to mathematicians and physicists who are interested in fu...

  17. InAs/GaSb/AlSb composite quantum well structure preparation with help of reflectance anisotropy spectroscopy

    Czech Academy of Sciences Publication Activity Database

    Hospodková, Alice; Hulicius, Eduard; Pangrác, Jiří; Dominec, Filip; Mikhailova, M. P.; Veinger, A.I.; Kochman, I.V.

    2017-01-01

    Roč. 464, Apr (2017), s. 206-210 ISSN 0022-0248 R&D Projects: GA MŠk LM2015087; GA MŠk LO1603 Institutional support: RVO:68378271 Keywords : low dimensional structures * MOVPE * InAs/GaSb composite quantum wells * AlSb Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 1.751, year: 2016

  18. Molecular quantum mechanical gradients within the polarizable embedding approach—Application to the internal vibrational Stark shift of acetophenone

    DEFF Research Database (Denmark)

    List, Nanna Holmgaard; Beerepoot, Maarten; Olsen, Jógvan Magnus Haugaard

    2015-01-01

    We present an implementation of analytical quantum mechanical molecular gradients within the polarizable embedding (PE) model to allow for efficient geometry optimizations and vibrational analysis of molecules embedded in large, geometrically frozen environments. We consider a variational ansatz...... for the quantum region, covering (multiconfigurational) self-consistent-field and Kohn–Sham density functional theory. As the first application of the implementation, we consider the internal vibrational Stark effect of the C=O group of acetophenone in different solvents and derive its vibrational linear Stark...... and water is essential in order to capture the structural modifications and the associated frequency shifts observed in water. For more apolar solvents, a proper description of dispersion and exchange–repulsion becomes increasingly important, and the quality of the optimized structures relies to a larger...

  19. Access to health care as a human right in international policy: critical reflections and contemporary challenges.

    Science.gov (United States)

    Castillo, Camilo Hernán Manchola; Garrafa, Volnei; Cunha, Thiago; Hellmann, Fernando

    2017-07-01

    Using the United Nations (UN) and its subordinate body, the World Health Organization (WHO), as a frame of reference, this article explores access to healthcare as a human right in international intergovernmental policies. First, we look at how the theme of health is treated within the UN, focusing on the concept of global health. We then discuss the concept of global health from a human rights perspective and go on to outline the debate surrounding universal coverage versus universal access as a human right, addressing some important ethical questions. Thereafter, we discuss universal coverage versus universal access using the critical and constructivist theories of international relations as a frame of reference. Finally, it is concluded that, faced with the persistence of huge global health inequalities, the WHO began to reshape itself, leaving behind the notion of health as a human right and imposing the challenge of reducing the wide gap that separates international intergovernmental laws from reality.

  20. International migration and the global agenda: reflections on the 1998 UN Technical Symposium.

    Science.gov (United States)

    Castles, S

    1999-01-01

    This article reviews the nature of discussions at the 1998 UN Technical Symposium on International Migration and Development. The Symposium reviewed the literature linking migration and development and successful policy approaches. Several themes emerged. A research framework is needed for accounting for all types of population mobility at all stages of the migratory process. Research should integrate contributions from a range of disciplines. The influence of social networks and cultural capital has grown in importance. Strategies need to account for women's experiences, which involve both empowerment and exploitation. Strategies need to consider return migration and better public information on migration and settlement. It was agreed that there is a need for a variety of quantitative and qualitative approaches and multidimensional analysis. The links between migration and development are complex, but sufficient information is available to greatly improve policy formation and international cooperation. National level responses have occasionally eroded the rights and protection of migrants. Few countries have adopted the 1990 UN Convention on the Rights of Migrant Workers and their Families and ILO Conventions 97 and 143. A prominent realization was that international cooperation did matter. International migration should be viewed as an opportunity for cooperation and development.

  1. Improving adolescent sexual and reproductive health in Latin America: reflections from an International Congress

    NARCIS (Netherlands)

    Córdova Pozo, K.; Chandra-Mouli, V.; Decat, P.; Nelson, E.; de Meyer, S.; Jaruseviciene, L.; Vega, B.; Segura, Z.; Auquilla, N.; Hagens, A.; van Braeckel, D.; Michielsen, K.

    2015-01-01

    In February 2014, an international congress on Promoting Adolescent Sexual and Reproductive Health (ASRH) took place in Cuenca, Ecuador. Its objective was to share evidence on effective ASRH intervention projects and programs in Latin America, and to link this evidence to ASRH policy and program

  2. Improving International Marketing Programs to Reflect Global Complexity and Risk: Curriculum Drivers and Constraints

    Science.gov (United States)

    Vos, Lynn

    2013-01-01

    This article looks at the curriculum redesign of a master's-level program in international marketing from a UK perspective. In order to ensure that the program would be more fit-for-purpose for future managers working under conditions of complexity, uncertainty, and within regimes often very different from the home market, the team began the…

  3. [Reflections on the concept of communication: second international goal of patient safety].

    Science.gov (United States)

    Medrano-Mariscal, Joel

    2015-01-01

    Effective communication is an element of prime importance, especially as it relates to health professional staff. Reflect on the concept and its meaning in a specific sector, taking into account their cultural and socio-environmental, requires interdisciplinary assistance in this case tools of medical anthropology as the emic view retake and construction of indicators are proposed. Medical anthropology and other social sciences, shows that the emic communication approach transcends the individual; so it is important to emphasize that communication has to be understood as a social construction, which helps to achieve understanding between people. Only from understanding the other will be able to think of an effective communication between health professionals.

  4. After Fukushima? On the educational and learning theoretical reflection of nuclear disasters. International perspectives

    International Nuclear Information System (INIS)

    Wigger, Lothar; Buenger, Carsten

    2017-01-01

    The book on the educational and learning theoretical reflection of nuclear disasters as a consequence of Fukushima includes contributions on the following issues: pedagogical approach: children write on Fukushima, description of the reality as pedagogical challenge; lessons learned on the nuclear technology - perspectives and limits of pedagogical evaluation: moral education - Japanese teaching materials, educational challenges at the universities with respect to nuclear technology and technology impact assessment; education and technology - questions concerning the pedagogical responsibility: considerations on the responsibility of scientists, on the discrepancy between technology and education, disempowerment of the public by structural corruption - nuclear disaster and post-democratic tendencies in Japan.

  5. Quantum memory Quantum memory

    Science.gov (United States)

    Le Gouët, Jean-Louis; Moiseev, Sergey

    2012-06-01

    quest for higher efficiency, better fidelity, broader bandwidth, multimode capacity and longer storage lifetime is pursued in all those approaches, as shown in this special issue. The improvement of quantum memory operation specifically requires in-depth study and control of numerous physical processes leading to atomic decoherence. The present issue reflects the development of rare earth ion doped matrices offering long lifetime superposition states, either as bulk crystals or as optical waveguides. The need for quantum sources and high efficiency detectors at the single photon level is also illustrated. Several papers address the networking of quantum memories either in long-haul cryptography or in the prospect of quantum processing. In this context, much attention has been paid recently to interfacing quantum light with superconducting qubits and with nitrogen-vacancy centers in diamond. Finally, the quantum interfacing of light with matter raises questions on entanglement. The last two papers are devoted to the generation of entanglement by dissipative processes. It is shown that long lifetime entanglement may be built in this way. We hope this special issue will help readers to become familiar with the exciting field of ensemble-based quantum memories and will stimulate them to bring deeper insights and new ideas to this area.

  6. Developing international open science collaborations: Funder reflections on the Open Science Prize.

    Science.gov (United States)

    Kittrie, Elizabeth; Atienza, Audie A; Kiley, Robert; Carr, David; MacFarlane, Aki; Pai, Vinay; Couch, Jennifer; Bajkowski, Jared; Bonner, Joseph F; Mietchen, Daniel; Bourne, Philip E

    2017-08-01

    The Open Science Prize was established with the following objectives: first, to encourage the crowdsourcing of open data to make breakthroughs that are of biomedical significance; second, to illustrate that funders can indeed work together when scientific interests are aligned; and finally, to encourage international collaboration between investigators with the intent of achieving important innovations that would not be possible otherwise. The process for running the competition and the successes and challenges that arose are presented.

  7. International competence and knowledge studies and attitudes of the Brazilian Management accountant: analyses and reflections

    Directory of Open Access Journals (Sweden)

    Ricardo Lopes Cardoso

    2010-01-01

    Full Text Available The main purpose of this study is to understand what the competences of the Management accountant are, compare to international studies and assess the existence of competences to be prioritized. This questioning has as motivation the placements of Hardern (1995, Morgan (1997, IMA (1996 e 1999 and IFAC (2003. The theoretical basis about competences is related to McClelland study (1973, 1998, Boyatzis (1982 and Spencer and Spencer (1993. This research is based on the study of 18 competences about knowledge, skills and attitudes obtained in accountant literature and that have been submitted to 200 Management accountants. Data collection instrument presented a 0.884 Cronbach Alpha. From a factorial analysis and after Kruskal-Wallis test 12 competences were obtained as the most relevant segregated in 3 factors, in comparison to international studies of nine common competences 4 were not considered relevant in statistical tests and only one must be prioritized. Results demonstrate differences between competences required from Brazilian Management accountants and from other countries, being that their reasons is an open-ended question up to the moment.

  8. Fluctuations of Internal Transmittance in Security of Measurement-Device-Independent Quantum Key Distribution with an Untrusted Source*

    International Nuclear Information System (INIS)

    Wang Yang; Bao Wan-Su; Chen Rui-Ke; Zhou Chun; Jiang Mu-Sheng; Li Hong-Wei

    2017-01-01

    Measurement-device-independent quantum key distribution (MDI-QKD) is immune to detector side channel attacks, which is a crucial security loophole problem in traditional QKD. In order to relax a key assumption that the sources are trusted in MDI-QKD, an MDI-QKD protocol with an untrusted source has been proposed. For the security of MDI-QKD with an untrusted source, imperfections in the practical experiment should also be taken into account. In this paper, we analyze the effects of fluctuations of internal transmittance on the security of a decoy-state MDI-QKD protocol with an untrusted source. Our numerical results show that both the secret key rate and the maximum secure transmission distance decrease when taken fluctuations of internal transmittance into consideration. Especially, they are more sensitive when Charlie’s mean photon number per pulse is smaller. Our results emphasize that the stability of correlative optical devices is important for practical implementations . (paper)

  9. Indigenous Storytelling and Participatory Action Research: Allies Toward Decolonization? Reflections From the Peoples' International Health Tribunal.

    Science.gov (United States)

    Caxaj, C Susana

    2015-01-01

    Storytelling, in its various forms, has often been described as a practice with great emancipatory potential. In turn, Indigenous knowledge shows great promise in guiding a participatory action research (PAR) methodology. Yet these two approaches are rarely discussed in relation to one another, nor, has much been written in terms of how these two approaches may work synergistically toward a decolonizing research approach. In this article, I report on a community-driven knowledge translation activity, the Peoples' International Health Tribunal, as an exemplar of how narrative and PAR approaches, guided by local Indigenous knowledge, have great potential to build methodologically and ethically robust research processes. Implications for building globally relevant research alliances and scholarship are further discussed, particularly in relation to working with Indigenous communities.

  10. Is law failing to address air pollution? Reflections on international and EU developments.

    Science.gov (United States)

    Yamineva, Yulia; Romppanen, Seita

    2017-11-01

    Air pollution is a major global environmental problem, with various adverse effects on health and the environment. This introductory article provides an overview of related global and regional legal instruments. The article evaluates the legal landscape in terms of its coverage, geographic scope and effectiveness, and concludes that the legal measures currently in place fall far short of providing an adequate response to the problem of air pollution. Thus, there is a clear need to strengthen global and regional cooperation to improve air quality. Such cooperation is likely to take non-binding and flexible forms and involve both wider participation among States and broader engagement of various stakeholders. The informal character of cooperation also makes it possible to experiment with new governance approaches that are difficult to implement within the context of traditional international law.

  11. Enhancement of cell internalization and photostability of red and green emitter quantum dots upon entrapment in novel cationic nanoliposomes.

    Science.gov (United States)

    Samadikhah, Hamid Reza; Nikkhah, Maryam; Hosseinkhani, Saman

    2017-06-01

    Two quantum dots (QDs), a green emitter, CdSe and a red emitter, CdSe with ZnS shell are encapsulated into novel liposomes in two different formulations including cationic liposomes. Quantum dots have proven themselves as powerful inorganic fluorescent probes, especially for long-term, multiplexed imaging and detection. Upon delivery into a cell, in endocytic vesicles such as endosomes, their fluorescence is quenched. We have investigated the potential toxic effects, photophysical properties and cell internalization of QDs in new formulation of liposomes as an in vitro vesicle model. Entrapment of QDs into liposomes is brought about with a decrease in their intrinsic fluorescence and toxicities and an increase in their photostability and lifetime. The biomimetic lipid bilayer of liposomes provides high biocompatibility, thereby enhancing the effectiveness of fluorescent nanoparticles for biological recognition in vitro and in vivo. The prepared lipodots could effectively prevent QDs from photo-oxidation during storage and when exposed to ultraviolet (UV) light. Moreover, the flow cytometry of HEK 293 T cells showed that the cell internalization of encapsulated QDs in (DSPC/CHO/DOPE/DOAB) liposome is enhanced 10 times compared with non-encapsulated QD (bare QDs). Copyright © 2016 John Wiley & Sons, Ltd.

  12. The International Association of Hydrogeologists (IAH): reflecting on 60 years of contributions to groundwater science and water management

    Science.gov (United States)

    Struckmeier, Willi; Howard, Ken; Chilton, John

    2016-08-01

    The 60th anniversary of the founding of the International Association of Hydrogeologists (IAH) is an important milestone that allows pause for reflection on how the association has evolved over the years and the contributions it has made to groundwater science and water management. IAH was founded in 1956 at the 20th International Geological Congress and developed rapidly during the 1980s and 1990s in response to a growing global interest in groundwater mapping and in sound approaches to resource protection and sustainable aquifer management. Incorporated in 2000, IAH has now secured its position as the world's leading international association specialising in groundwater with over 4,100 members in 131 countries. Much credit for this success must go to members, past and present, whose individual efforts and collaboration with sister institutions are documented here. These members have shaped the association's goals and contributed selflessly to its scientific programmes, publications and educational and charitable activities. Looking ahead to the next 60 years, it is essential that IAH does not rest on past achievements but listens and adjusts to the needs of members while continuing to pursue its mission of furthering the understanding, wise use and protection of groundwater resources throughout the world.

  13. 'How would you call this in English?' : Being reflective about translations in international, cross-cultural qualitative research.

    Science.gov (United States)

    Helmich, Esther; Cristancho, Sayra; Diachun, Laura; Lingard, Lorelei

    2017-04-01

    Medical education researchers increasingly collaborate in international teams, collecting data in different languages and from different parts of the world, and then disseminating them in English-language journals. Although this requires an ever-present need to translate, it often occurs uncritically. With this paper we aim to enhance researchers' awareness and reflexivity regarding translations in qualitative research. In an international study, we carried out interviews in both Dutch and English. To enable joint data analysis, we translated Dutch data into English, making choices regarding when and how to translate. In an iterative process, we contextualized our experiences, building on the social sciences and general health literature about cross-language/cross-cultural research. We identified three specific translation challenges: attending to grammar or syntax differences, grappling with metaphor, and capturing semantic or sociolinguistic nuances. Literature findings informed our decisions regarding the validity of translations, translating in different stages of the research process, coding in different languages, and providing 'ugly' translations in published research reports. The lessons learnt were threefold. First, most researchers, including ourselves, do not consciously attend to translations taking place in international qualitative research. Second, translation challenges arise not only from differences in language, but also from cultural or societal differences. Third, by being reflective about translations, we found meaningful differences, even between settings with many cultural and societal similarities. This conscious process of negotiating translations was enriching. We recommend researchers to be more conscious and transparent about their translation strategies, to enhance the trustworthiness and quality of their work.

  14. Fast Focal Point Correction in Prism-Coupled Total Internal Reflection Scanning Imager Using an Electronically Tunable Lens.

    Science.gov (United States)

    Zhu, Chenggang; Ge, Bilin; Chen, Ru; Zhu, Xiangdong; Mi, Lan; Ma, Jiong; Wang, Xu; Zheng, Fengyun; Fei, Yiyan

    2018-02-09

    Total internal reflection (TIR) is useful for interrogating physical and chemical processes that occur at the interface between two transparent media. Yet prism-coupled TIR imaging microscopes suffer from limited sensing areas due to the fact that the interface (the object plane) is not perpendicular to the optical axis of the microscope. In this paper, we show that an electrically tunable lens can be used to rapidly and reproducibly correct the focal length of an oblique-incidence scanning microscope (OI-RD) in a prism-coupled TIR geometry. We demonstrate the performance of such a correction by acquiring an image of a protein microarray over a scan area of 4 cm² with an effective resolution of less than 20 microns. The electronic focal length tuning eliminates the mechanical movement of the illumination lens in the scanning microscope and in turn the noise and background drift associated with the motion.

  15. Fast Focal Point Correction in Prism-Coupled Total Internal Reflection Scanning Imager Using an Electronically Tunable Lens

    Directory of Open Access Journals (Sweden)

    Chenggang Zhu

    2018-02-01

    Full Text Available Total internal reflection (TIR is useful for interrogating physical and chemical processes that occur at the interface between two transparent media. Yet prism-coupled TIR imaging microscopes suffer from limited sensing areas due to the fact that the interface (the object plane is not perpendicular to the optical axis of the microscope. In this paper, we show that an electrically tunable lens can be used to rapidly and reproducibly correct the focal length of an oblique-incidence scanning microscope (OI-RD in a prism-coupled TIR geometry. We demonstrate the performance of such a correction by acquiring an image of a protein microarray over a scan area of 4 cm2 with an effective resolution of less than 20 microns. The electronic focal length tuning eliminates the mechanical movement of the illumination lens in the scanning microscope and in turn the noise and background drift associated with the motion.

  16. Enhanced detection sensitivity of carcinoembryonic antigen on a plasmonic nanoimmunosensor by transmission grating-based total internal reflection scattering microscopy.

    Science.gov (United States)

    Ahn, Sujin; Yu, Hyunung; Kang, Seong Ho

    2017-10-15

    Carcinoembryonic antigen (CEA) is a glycoprotein associated with colorectal carcinomas and is commonly used as a clinical tumor marker. Enhanced detection sensitivity for the assay of CEA molecules was achieved on a plasmonic nanoimmunosensor by wavelength-dependent transmission grating (TG)-based total internal reflection scattering microscopy (TIRSM). The plasmonic nanoparticles were placed in an evanescent field layer on a glass nanoimmunosensor that produced evanescent wave scattering by the total internal reflection of light from two lasers. The light scattered by target protein (CEA)-bound 20-nm silver nanoparticles (plasmonic nanoprobes) was collected and spectrally isolated in first-order spectral images (n=+1) by a TG (70 grooves/mm). The combination of evanescent wave scattering and TG ​significantly enhanced the detection sensitivity and selectivity due to the minimized spectroscopic interference and background noise. The TG-TIRSM method detected the CEA molecules at concentrations down to 19.75zM with a wide linear dynamic range of 19.75zM-39.50nM (correlation coefficient, R=0.9903), which was 45 to 1.25×10 9 times lower than the detection limits and 2×10 5 to 2×10 11 times wider than the dynamic ranges of previous assay methods. In particular, by simply changing the antibody of the target molecule, this technique can be used to detect various disease-related protein biomarkers directly in human biological samples at the single-molecule level. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Probing the internal energy structure of a serially coupled double quantum dot system with Rashba spin-orbit coupling through finite-frequency shot noise

    Science.gov (United States)

    Xue, Hai-Bin; Liu, Xu-Ping; Chen, Bin

    2018-01-01

    The finite-frequency shot noise of electron transport through a serially coupled double quantum dot system with Rashba spin-orbit coupling is studied based on an effective particle-number-resolved quantum master equation. We demonstrate that the finite-frequency shot noise displays an obvious dip, and the dip position, which is independent of the spin polarizations of the source and drain electrodes, is determined by the energy difference between the coherent singly-occupied eigenstates of the quantum dot system. These results suggest that the dip position of the finite-frequency shot noise can be used to quantitatively extract the information about the energy difference between the coherent singly-occupied eigenstates and the magnitude of Rashba spin-orbit coupling. The predicted properties of the finite-frequency shot noise are of particular interest for understanding of the internal dynamics of the coupled quantum dot systems.

  18. Reflection Positive Doubles

    OpenAIRE

    Jaffe, Arthur; Janssens, Bas

    2016-01-01

    Here we introduce reflection positive doubles, a general framework for reflection positivity, covering a wide variety of systems in statistical physics and quantum field theory. These systems may be bosonic, fermionic, or parafermionic in nature. Within the framework of reflection positive doubles, we give necessary and sufficient conditions for reflection positivity. We use a reflection-invariant cone to implement our construction. Our characterization allows for a direct interpretation in t...

  19. Quantum electrodynamics of the internal source x-ray holographies: Bremsstrahlung, fluorescence, and multiple-energy x-ray holography

    International Nuclear Information System (INIS)

    Miller, G.A.; Sorensen, L.B.

    1997-01-01

    Quantum electrodynamics (QED) is used to derive the differential cross sections measured in the three new experimental internal source ensemble x-ray holographies: bremsstrahlung (BXH), fluorescence (XFH), and multiple-energy (MEXH) x-ray holography. The polarization dependence of the BXH cross section is also obtained. For BXH, we study analytically and numerically the possible effects of the virtual photons and electrons which enter QED calculations in summing over the intermediate states. For the low photon and electron energies used in the current experiments, we show that the virtual intermediate states produce only very small effects. This is because the uncertainty principle limits the distance that the virtual particles can propagate to be much shorter than the separation between the regions of high electron density in the adjacent atoms. We also find that using the asymptotic form of the scattering wave function causes about a 5 10% error for near forward scattering. copyright 1997 The American Physical Society

  20. Semi-automatic engineering and tailoring of high-efficiency Bragg-reflection waveguide samples for quantum photonic applications

    Science.gov (United States)

    Pressl, B.; Laiho, K.; Chen, H.; Günthner, T.; Schlager, A.; Auchter, S.; Suchomel, H.; Kamp, M.; Höfling, S.; Schneider, C.; Weihs, G.

    2018-04-01

    Semiconductor alloys of aluminum gallium arsenide (AlGaAs) exhibit strong second-order optical nonlinearities. This makes them prime candidates for the integration of devices for classical nonlinear optical frequency conversion or photon-pair production, for example, through the parametric down-conversion (PDC) process. Within this material system, Bragg-reflection waveguides (BRW) are a promising platform, but the specifics of the fabrication process and the peculiar optical properties of the alloys require careful engineering. Previously, BRW samples have been mostly derived analytically from design equations using a fixed set of aluminum concentrations. This approach limits the variety and flexibility of the device design. Here, we present a comprehensive guide to the design and analysis of advanced BRW samples and show how to automatize these tasks. Then, nonlinear optimization techniques are employed to tailor the BRW epitaxial structure towards a specific design goal. As a demonstration of our approach, we search for the optimal effective nonlinearity and mode overlap which indicate an improved conversion efficiency or PDC pair production rate. However, the methodology itself is much more versatile as any parameter related to the optical properties of the waveguide, for example the phasematching wavelength or modal dispersion, may be incorporated as design goals. Further, we use the developed tools to gain a reliable insight in the fabrication tolerances and challenges of real-world sample imperfections. One such example is the common thickness gradient along the wafer, which strongly influences the photon-pair rate and spectral properties of the PDC process. Detailed models and a better understanding of the optical properties of a realistic BRW structure are not only useful for investigating current samples, but also provide important feedback for the design and fabrication of potential future turn-key devices.

  1. Polynomial deformations of oscillator algebras in quantum theories with internal symmetries

    International Nuclear Information System (INIS)

    Karassiov, V.P.

    1992-01-01

    This paper reports that for last years some new Lie-algebraic structures (quantum groups or algebras, W-algebras, Casimir algebras) have been introduced in different areas of modern physics. All these objects are non-linear generalizations (deformations) of usual (linear) Lie algebras which are generated by a set B = {T a } of their generators T a satisfying a commutation relations (CR) of the form [T a , T b ] = f ab ({T c }) where f ab (...) are some functions of the generators T c given by power series. From the mathematical viewpoint such objects called as nonlinear or deformed Lie algebras G d may be treated as universal algebras or algebraic systems G d = left-angle B; +, · , [,] right-angle generated by a basic set B and the usual operations of the addition (+) and the multiplication (·) together with the Lie product ([T a , T b ] = T a T b - T b T a )

  2. Intrinsic quantum computation

    International Nuclear Information System (INIS)

    Crutchfield, James P.; Wiesner, Karoline

    2008-01-01

    We introduce ways to measure information storage in quantum systems, using a recently introduced computation-theoretic model that accounts for measurement effects. The first, the quantum excess entropy, quantifies the shared information between a quantum process's past and its future. The second, the quantum transient information, determines the difficulty with which an observer comes to know the internal state of a quantum process through measurements. We contrast these with von Neumann entropy and quantum entropy rate and provide a closed-form expression for the latter for the class of deterministic quantum processes

  3. Direct visualization of the reaction transformation and signal amplification in a DNA molecular machine with total internal reflection fluorescence microscopy

    Directory of Open Access Journals (Sweden)

    Rui eRen

    2013-10-01

    Full Text Available In this study, as a proof of concept, the signal amplification in an artificial DNA molecular machine was directly visualized via total internal reflection fluorescence microscopy (TIRFM. The molecular machine brought about obvious morphology change in DNA nanostructures as well as signal amplifications. On one hand, through a triggered and autonomically repeated RCA, a DNA nano-complex featuring a locked circular DNA template (serving as raw feed was converted into a long periodically repeated strand, i.e. the RCA products. Furthermore, this RCA was repeated in three controllable reaction phases, bring about progressive signal amplification. It was testified that the RCA products (presented as long thread-like fluorescent objects can be easily distinguished from the inputted DNA probes (presented as fluorescent dots, thus the transformation in reaction can be visualized. Also, by quantitive counting of the aforementioned fluorescence objects, the progress of the reaction through the phases, along with time, and over the lysozyme concentration can be demonstrated through TIRFM visualization. Overall, it was demonstrated that TIRFM is an efficient approach to quantitively visualize the biochemical processes at single-molecule level.

  4. Planar solar concentrator featuring alignment-free total-internal-reflection collectors and an innovative compound tracker.

    Science.gov (United States)

    Teng, Tun-Chien; Lai, Wei-Che

    2014-12-15

    This study proposed a planar solar concentrator featuring alignment-free total-internal-reflection (TIR) collectors and an innovative compound tracker. The compound tracker, combining a mechanical single-axis tracker and scrollable prism sheets, can achieve a performance on a par with dual-axis tracking while reducing the cost of the tracking system and increasing its robustness. The alignment-free TIR collectors are assembled on the waveguide without requiring alignment, so the planar concentrator is relatively easily manufactured and markedly increases the feasibility for use in large concentrators. Further, the identical TIR collector is applicable to various-sized waveguide slab without requiring modification, which facilitates flexibility regarding the size of the waveguide slab. In the simulation model, the thickness of the slab was 2 mm, and its maximal length reached 6 m. With an average angular tolerance of ±0.6°, and after considering both the Fresnel loss and the angular spread of the sun, the simulation indicates that the waveguide concentrator of a 1000-mm length provides the optical efficiencies of 62-77% at the irradiance concentrations of 387-688, and the one of a 2000-mm length provides the optical efficiencies of 52-64.5% at the irradiance concentrations of 645-1148. Alternatively, if a 100-mm horizontally staggered waveguide slab is collocated with the alignment-free TIR collectors, the optical efficiency would be greatly improved up to 91.5% at an irradiance concentration of 1098 (C(geo) = 1200X).

  5. Real time study of amalgam formation and mercury adsorption on thin gold film by total internal reflection ellipsometry

    Science.gov (United States)

    Paulauskas, A.; Selskis, A.; Bukauskas, V.; Vaicikauskas, V.; Ramanavicius, A.; Balevicius, Z.

    2018-01-01

    Total internal reflection ellipsometry (TIRE) was utilized in its dynamic data acquisition mode to reveal the percentage of mercury present in an amalgam surface layer. In determining the optical constants of the amalgam film, the non-homogeneities of the formed surface layer were taken into account. The composition of the amalgam layer by percentage was determined using the EMA Bruggemann model for the analysis of the TIRE data. Regression results showed that amalgam layer consisted of mercury 16.00 ± 0.43% and gold 84.00 ± 0.43%. This real time TIRE analysis has shown that for these studies method can detect 0.6 ± 0.4% of mercury on a gold surface, proving that this is a suitable optical technique for obtaining real time readouts. The structural analysis of SEM and AFM have shown that the amalgam layer had a dendritic structure, which formation was determined by the weak adhesion of the gold atoms onto its surface.

  6. Removing the effect of blooming from potential energy measurement by employing total internal reflection microscopy integrated with video microscopy.

    Science.gov (United States)

    Cao, Feng; Gong, Xiangjun; He, Chuanxin; Ngai, To

    2017-10-01

    Total internal reflection microscopy (TIRM) measures the interactions between a colloidal particle and a flat surface in aqueous solution. Recently, TIRM has further integrated with video microscopy (VM) and enabled the simultaneous measurements of multi-particle colloid-surface interactions in the same ensemble. However, there still remain challenges about accurate image acquisition due to blooming. Blooming means the number of photons reaching the detector exceeds its maximum capacity, and the excess photons will either spill to adjacent pixels or not be counted, leading to an obstacle from precise determination of intensity. Our result shows that blooming gives rise to a deviation of the measured potential energy from the classical theory of Derjaguin, Landau, Verway, and Overbeek (DLVO). Therefore, a correction method was developed in this work to deduce the real intensity from the experimental measurement. The relationship between scattered light intensity and exposure time deviates from linearity when blooming occurs. A correction equation was developed to recover the real intensity, which was then confirmed by the accordance between the corresponding potential energy profiles and the DLVO theory. This correction method is suitable for VM systems of colloidal probes illuminated by scattered light, broadening the application of VM imaging to investigate colloidal interactions. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. The Advantages of an Attenuated Total Internal Reflection Infrared Microspectroscopic Imaging Technique for the Analysis of Polymer Laminates.

    Science.gov (United States)

    Ling, Chen; Sommer, André J

    2015-06-01

    Until recently, the analysis of polymer laminates using infrared microspectroscopy involved the painstaking separation of individual layers by dissection or by obtaining micrometer thin cross-sections. The latter usually requires the expertise of an individual trained in microtomy and even then, the very structure of the laminate could affect the outcome of the spectral results. The recent development of attenuated total internal reflection (ATR) infrared microspectroscopy imaging has provided a new avenue for the analysis of these multilayer structures. This report compares ATR infrared microspectroscopy imaging with conventional transmission infrared microspectroscopy imaging. The results demonstrate that the ATR method offers improved spatial resolution, eliminates a variety of competing optical processes, and requires minimal sample preparation relative to transmission measurements. These advantages were illustrated using a polymer laminate consisting of 11 different layers whose thickness ranged in size from 4-20 μm. The spatial resolution achieved by using an ATR-FTIR (Fourier transform infrared spectroscopy) imaging technique was diffraction limited. Contrast in the ATR images was enhanced by principal component analysis.

  8. Studying flow close to an interface by total internal reflection fluorescence cross-correlation spectroscopy: Quantitative data analysis

    Science.gov (United States)

    Schmitz, R.; Yordanov, S.; Butt, H. J.; Koynov, K.; Dünweg, B.

    2011-12-01

    Total internal reflection fluorescence cross-correlation spectroscopy (TIR-FCCS) has recently [S. Yordanov , Optics ExpressOPEXFF1094-408710.1364/OE.17.021149 17, 21149 (2009)] been established as an experimental method to probe hydrodynamic flows near surfaces, on length scales of tens of nanometers. Its main advantage is that fluorescence occurs only for tracer particles close to the surface, thus resulting in high sensitivity. However, the measured correlation functions provide only rather indirect information about the flow parameters of interest, such as the shear rate and the slip length. In the present paper, we show how to combine detailed and fairly realistic theoretical modeling of the phenomena by Brownian dynamics simulations with accurate measurements of the correlation functions, in order to establish a quantitative method to retrieve the flow properties from the experiments. First, Brownian dynamics is used to sample highly accurate correlation functions for a fixed set of model parameters. Second, these parameters are varied systematically by means of an importance-sampling Monte Carlo procedure in order to fit the experiments. This provides the optimum parameter values together with their statistical error bars. The approach is well suited for massively parallel computers, which allows us to do the data analysis within moderate computing times. The method is applied to flow near a hydrophilic surface, where the slip length is observed to be smaller than 10nm, and, within the limitations of the experiments and the model, indistinguishable from zero.

  9. Temperature-reflection I

    DEFF Research Database (Denmark)

    McGady, David A.

    2017-01-01

    that T-reflection is unrelated to time-reversal. Finally, we study the interplay between T-reflection and perturbation theory in the anharmonic harmonic oscillator in quantum mechanics and in Yang-Mills in four-dimensions. This is the first in a series of papers on temperature-reflections.......In this paper, we revisit the claim that many partition functions are invariant under reflecting temperatures to negative values (T-reflection). The goal of this paper is to demarcate which partition functions should be invariant under T-reflection, and why. Our main claim is that finite......-temperature path integrals for quantum field theories (QFTs) should be T-reflection invariant. Because multi-particle partition functions are equal to Euclidean path integrals for QFTs, we expect them to be T-reflection invariant. Single-particle partition functions though are often not invariant under T...

  10. Blogging as a tool to promote reflection among dietetic and physical therapy students during a multidisciplinary international service-learning experience.

    Science.gov (United States)

    Wright, Lauri; Lundy, Mary

    2012-01-01

    Service-learning is a guided, structured learning experience that engages students in service to a community for the mutual benefit of the student and community. There is a growing trend in healthcare to include international service-learning experiences in the training curriculum to promote cultural competence. A critical element of service-learning is reflection. There have been many research studies examining how best to support and facilitate the reflective thinking process in students. The purpose of this study was to assess the development of reflective thinking among graduate allied health students during an interdisciplinary international service-learning experience using a web-based collaborative blog. Twelve graduate students-six dietetic interns and six physical therapy doctoral students-traveled to Belize for 6 days to provide primary healthcare screenings and intervention to a community. Group blogging was found to be an effective tool to promote reflection in allied health student and short duration service-learning experience developed reflective thinking.

  11. Invited Article: An active terahertz polarization converter employing vanadium dioxide and a metal wire grating in total internal reflection geometry

    Science.gov (United States)

    Liu, Xudong; Chen, Xuequan; Parrott, Edward P. J.; Han, Chunrui; Humbert, Georges; Crunteanu, Aurelian; Pickwell-MacPherson, Emma

    2018-05-01

    Active broadband terahertz (THz) polarization manipulation devices are challenging to realize, but also of great demand in broadband terahertz systems. Vanadium dioxide (VO2) shows a promising phase transition for active control of THz waves and provides broadband polarization characteristics when integrated within grating-type structures. We creatively combine a VO2-based grating structure with a total internal reflection (TIR) geometry providing a novel interaction mechanism between the electromagnetic waves and the device, to realize a powerful active broadband THz polarization-controlling device. The device is based on a Si-substrate coated with a VO2 layer and a metal grating structure on top, attached to a prism for generating the TIR condition on the Si-VO2-grating interface. The grating is connected to electrodes for electrically switching the VO2 between its insulating and conducting phases. By properly selecting the incident angle of the THz waves, the grating direction, and the incident polarization state, we first achieved a broadband intensity modulator under a fused silica prism with an average modulation depth of 99.75% in the 0.2-1.1 THz region. Additionally, we realized an active ultra-broadband quarter-wave converter under a Si prism that can be switched between a 45° linear rotator and a quarter wave converter in the 0.8-1.5 THz region. This is the first demonstration of an active quarter-wave converter with ultra-broad bandwidth performance. Our work shows a highly flexible and multifunctional polarization-controlling device for broadband THz applications.

  12. Experimental and numerical studies of the scattering of light from a two-dimensional randomly rough interface in the presence of total internal reflection: optical Yoneda peaks.

    Science.gov (United States)

    González-Alcalde, Alma K; Banon, Jean-Philippe; Hetland, Øyvind S; Maradudin, Alexei A; Méndez, Eugenio R; Nordam, Tor; Simonsen, Ingve

    2016-11-14

    The scattering of polarized light from a dielectric film sandwiched between two different semi-infinite dielectric media is studied experimentally and theoretically. The illuminated interface is planar, while the back interface is a two-dimensional randomly rough interface. We consider here only the case in which the medium of incidence is optically more dense than the substrate, in which case effects due to the presence of a critical angle for total internal reflection occur. A reduced Rayleigh equation for the scattering amplitudes is solved by a rigorous, purely numerical, nonperturbative approach. The solutions are used to calculate the reflectivity of the structure and the mean differential reflection coefficient. Optical analogues of Yoneda peaks are present in the results obtained. The computational results are compared with experimental data for the in-plane mean differential reflection coefficient, and good agreement between theory and experiment is found.

  13. Non-Covalent Interactions and Internal Dynamics in Pyridine-Ammonia a Combined Quantum-Chemical and Microwave Spectroscopy Study

    Science.gov (United States)

    Spada, Lorenzo; Tasinato, Nicola; Vazart, Fanny; Barone, Vincenzo; Caminati, Walther; Puzzarini, Cristina

    2017-06-01

    The 1:1 complex of ammonia with pyridine has been characterized by using state-of-the-art quantum-chemical computations combined with pulsed-jet Fourier-Transform microwave spectroscopy. The computed potential energy landscape pointed out the formation of a stable σ-type complex, which has been confirmed experimentally: the analysis of the rotational spectrum showed the presence of only one 1:1 pyridine - ammonia adduct. Each rotational transition is split into several components due to the internal rotation of NH_3 around its C_3 axis and to the hyperfine structure of both ^{14}N quadrupolar nuclei, thus providing the unequivocal proof that the two molecules form a σ-type complex involving both a N-H\\cdotsN and a C-H\\cdotsN hydrogen bond. The dissociation energy (BSSE and ZPE corrected) has been estimated to be 11.5 kJ\\cdotmol^{-1}. This work represents the first application of an accurate, yet efficient computational scheme, designed for the investigation of small biomolecules, to a molecular cluster.

  14. High-field spin dynamics of antiferromagnetic quantum spin chains

    DEFF Research Database (Denmark)

    Enderle, M.; Regnault, L.P.; Broholm, C.

    2000-01-01

    present recent work on the high-field spin dynamics of the S = I antiferromagnetic Heisenberg chains NENP (Haldane ground state) and CsNiCl3 (quasi-1D HAF close to the quantum critical point), the uniform S = 1/2 chain CTS, and the spin-Peierls system CuGeO3. (C) 2000 Elsevier Science B,V. All rights......The characteristic internal order of macroscopic quantum ground states in one-dimensional spin systems is usually not directly accessible, but reflected in the spin dynamics and the field dependence of the magnetic excitations. In high magnetic fields quantum phase transitions are expected. We...

  15. Using an Intention/Reflection Practice to Focus Students towards Future Professions in a Short-Term International Travel Experience

    Science.gov (United States)

    Fierke, Kerry K.; Lepp, Gardner A.; Bastianelli, Karen; Vogelsang, Lisa; Tornabene, Ladona

    2016-01-01

    The article describes a student-centered approach to generating meaningful learning outcomes in a short-term study abroad program. A practice named Intention/Reflection (I/R) was used to help students to identify, articulate, and reflect upon learning objectives that were personally meaningful, within the broader framework of the intended outcomes…

  16. Reflection Positivity and Monotonicity

    OpenAIRE

    Ritter, Gordon; Jaffe, Arthur Michael

    2008-01-01

    We prove general reflection positivity results for both scalar fields and Dirac fields on a Riemannian manifold, and comment on applications to quantum field theory. As another application, we prove the inequality \\(C_D \\leq C_N\\) between Dirichlet and Neumann covariance operators on a manifold with a reflection.

  17. Pressler's Quantumization of the Atom and The Left-handed Electron's Internal Structure

    Science.gov (United States)

    Pressler, David E.

    2000-03-01

    A new theory of superconductivity will be presented. In addition, I will reveal the answer to one of the most intriguing questions in science since the elusive electron particle was discovered by J. J. Thomson: Exactly what is the electron particle and why does it exhibit both particle and wave characteristics. Specifically, how does the electron exhibit an intrinsic magnetic field and, inside the atom, how does it exhibit angular momentum. I will describe, in detail, particle pair production. The fundamental physical theoretical parameters, the physical mass and charge, of all elementary particles is introduced. The fundamental neutron particle’s internal structure is also illustrated. The electron radius is estimated to eight significant figures. I will present a novel theory concerning atomic structure, the position and nature of the electron inside the atom, and the nature of bonding, i.e., the covalent bond is described in terms of the interactions of atomic magnetic fields. Precise bond angles and distances of the molecule are considered. This new concept is consistent with experimental evidence and adheres strictly to the valence-shell electron-pair repulsion (VSEPR) model presently used in chemistry. I will explain the atomic model concept as being a true harmonic oscillator; periodic motion of the electron at resonant frequency produces radiation at discrete frequencies or line spectra because the electron is under the action of two restoring forces.

  18. Accounting for Interference, Scattering, and Electrode Absorption to Make Accurate Internal Quantum Efficiency Measurements in Organic and Other Thin Solar Cells

    KAUST Repository

    Burkhard, George F.

    2010-05-31

    Accurately measuring internal quantum efficiency requires knowledge of absorption in the active layer of a solar cell. The experimentally accessible total absorption includes significant contributions from the electrodes and other nonactive layers. We suggest a straightforward method for calculating the active layer contribution that minimizes error by subtracting optically-modeled electrode absorption from experimentally measured total absorption. (Figure Presented) © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Immunities of International Organizations before Domestic Courts : Reflections on the Collective Labour Case against the European Patent Organization

    NARCIS (Netherlands)

    Ryngaert, C.M.J.

    2016-01-01

    The Netherlands is home to a substantial number of international organizations, which on the basis of international agreements are entitled to immunity from jurisdiction and enforcement before Dutch courts. This immunity grant has not stopped claimants from suing international organizations in The

  20. 3D study of a bi facial polycrystalline photovoltaic cell under constant magnetic field and determination of the parameters of recombination from internal quantum yield

    International Nuclear Information System (INIS)

    ZOUMA Bernard

    2010-01-01

    The work presented in this thesis deals with the problem of the quality of polycrystalline silicon solar cells. This work has been done on square surface columnar grains of the bi facial solar cell. This study ends in the determination of the quality of bi facial solar cells from their recombination parameters. We propose an useful technique to determine these recombination parameters from the algorithm calculation that is based on the internal quantum efficiency. A set of dimensional approach like the three-dimensional model of the solar cell that allows taking into account the grain size and grain boundaries recombination velocity. The emitter contribution and the terrestrial magnetic field influence are taken into account too. While lighted, the emitter region becomes a recombination zone of the electron from the base region. We have obtained a new exhaustive analytical expression of the internal quantum efficiency. This theoretical efficiency is a function of the recombination parameters and it is used to fit the experimental curves of the internal quantum efficiency versus the wavelength. The results are in a good agreement with the experimental values.(Author) [fr

  1. Problems in quantum mechanics

    CERN Document Server

    Constantinescu, Florin; Spiers, JA

    1971-01-01

    International Series in Natural Philosophy, Volume 30: Problems in Quantum Mechanics focuses on the processes, principles, reactions, and methodologies involved in quantum mechanics. The publication first elaborates on the mathematical formalism of quantum mechanics, simple quantum systems, and mean values and uncertainty relations. Discussions focus on mean values of dynamical variables, uncertainty relations, eigenfunctions and the energy spectrum, motion in a central field, matrix representation of vectors and operators, Hubert spaces, and operators in Hilbert space. The text then takes a l

  2. Quantum optics

    National Research Council Canada - National Science Library

    Agarwal, G. S

    2013-01-01

    .... Focusing on applications of quantum optics, the textbook covers recent developments such as engineering of quantum states, quantum optics on a chip, nano-mechanical mirrors, quantum entanglement...

  3. Quantum optics for engineers

    CERN Document Server

    Duarte, FJ

    2013-01-01

    Quantum Optics for Engineers provides a transparent and methodical introduction to quantum optics via the Dirac's bra-ket notation with an emphasis on practical applications and basic aspects of quantum mechanics such as Heisenberg's uncertainty principle and Schrodinger's equation. Self-contained and using mainly first-year calculus and algebra tools, the book:Illustrates the interferometric quantum origin of fundamental optical principles such as diffraction, refraction, and reflectionProvides a transparent introduction, via Dirac's notation, to the probability amplitude of quantum entanglem

  4. Conceptual Reflections on Ethics for International Research Collaborations in Disaster Impacted Areas from the Experiences in Indonesia, New Zealand and Japan

    Directory of Open Access Journals (Sweden)

    Christopher Gomez

    2014-12-01

    Full Text Available The present contribution is by no means a first attempt at considering the ethics in human activities, interactions in disaster impacted areas, but it is more the case of looking at 'international research' that present a very particular difficulty for ethics: the notion of trans-boundary, multi-dimensional idea of one group not really belonging within another, but which will perform functions inside this second group and eventually alter, modify some of the original organs. This paper explain the reflections of the ethical consideration of international research collaboration in disaster impacted areas which are emerged from the experiences in Indonesia, New Zealand and Japan.

  5. Implementing the First Cross-border Professional Development Online Course through International E-mentoring: Reflections and Perspectives

    Directory of Open Access Journals (Sweden)

    Buddhini Gayathri Jayatilleke

    2017-03-01

    Full Text Available This research paper discusses the accomplishments, issues, and challenges experienced by Open University of Sri Lanka (OUSL academics when offering the first cross-border professional development online course to train online tutors and mentors. The course was delivered exclusively online and facilitated by OUSL academics and e-mentors from the USA. The course was comprised of 30 participants: 9 from Pakistan, 10 from Mauritius and 11 from Sri Lanka. This qualitative study is based on reflections of both faculty and participants. Data were collected using reflections and informal anecdotal records of the three OUSL academics and self-reflection instruments (pre, mid and final administered to participants, and reflective journal entries made by participants. Participants’ views were triangulated with the reflections of the OUSL academics to validate the results. While there were many accomplishments in the design and delivery of the course, the findings revealed that there were many challenges in implementing the course: pedagogical, organizational and technological aspects in particular. The paper provides recommendations to address such challenges when offering cross-border online courses in the future.

  6. Rethinking the Employability of International Graduate Migrants: Reflections on the Experiences of Zimbabweans with Degrees from England

    Science.gov (United States)

    McGrath, Simon; Madziva, Roda; Thondhlana, Juliet

    2017-01-01

    The last decade has seen the rise of literature focused on the rapid expansion of international students in higher education globally and the growing policy discourse around improving graduate employability. However, both, inevitably, have limitations. Together, they tend to homogenise international learners and see them narrowly as simply…

  7. Quantum capacity of quantum black holes

    Science.gov (United States)

    Adami, Chris; Bradler, Kamil

    2014-03-01

    The fate of quantum entanglement interacting with a black hole has been an enduring mystery, not the least because standard curved space field theory does not address the interaction of black holes with matter. We discuss an effective Hamiltonian of matter interacting with a black hole that has a precise analogue in quantum optics and correctly reproduces both spontaneous and stimulated Hawking radiation with grey-body factors. We calculate the quantum capacity of this channel in the limit of perfect absorption, as well as in the limit of a perfectly reflecting black hole (a white hole). We find that the white hole is an optimal quantum cloner, and is isomorphic to the Unruh channel with positive quantum capacity. The complementary channel (across the horizon) is entanglement-breaking with zero capacity, avoiding a violation of the quantum no-cloning theorem. The black hole channel on the contrary has vanishing capacity, while its complement has positive capacity instead. Thus, quantum states can be reconstructed faithfully behind the black hole horizon, but not outside. This work sheds new light on black hole complementarity because it shows that black holes can both reflect and absorb quantum states without violating the no-cloning theorem, and makes quantum firewalls obsolete.

  8. Ethical principles in international nuclear trade and the role of international treaties and agreements in their implementation. Reflections on the future

    International Nuclear Information System (INIS)

    Cavalanti, C. de A.

    1992-01-01

    The growing importance of nuclear energy (on the threshold of the twenty-first century) and of its ethical uses is considered, including major political events in recent years, their social and economic consequences in the world scene. International Nuclear Law is seen as the most adequate instrument to promote the ethical uses of nuclear energy on a worldwide basis, so that mankind can benefit safely and properly and improving their living conditions in general. Problems associated with access to nuclear technology, plants, equipments and materials are addressed. Basic principles of international agreements ruling nuclear trade, ethical aspects are also covered. The different markets involved in international nuclear trade and their specific requirements are described. Certain international treaties on the peaceful uses of nuclear energy are discussed such as the Non-Proliferation Treaty and the Tlatelolco Treaty as are international conventions on matters related to the use of nuclear energy, such as the environment and protection of personnel. The author concludes by debating whether ethical uses of nuclear energy are a possible reality or merely utopia. Prospects on the future of international nuclear trade are considered. (author)

  9. College Athletes' Reflective Judgment: A Moderator between Sport and Sociocultural Pressures, Body Ideal Internalization, and Body Dissatisfaction

    Science.gov (United States)

    Greene, Catie A.

    2016-01-01

    The purpose of this research was to investigate the sociocultural model of eating disorder development among male and female college student-athletes as moderated by students' level of Reflective Judgment, a stage theory of adult epistemology marked by increasing cognitive complexity. A review of literature on the established relationships between…

  10. Proceedings of the 9th International Symposium on Foundations of Quantum Mechanics in the Light of New Technology

    Science.gov (United States)

    Ishioka, Sachio; Fujikawa, Kazuo

    2009-06-01

    Committee -- Obituary: Professor Sadao Nakajima -- Opening address / H. Fukuyama -- Welcoming address / N. Osakabe -- Cold atoms and molecules. Pseudopotential method in cold atom research / C. N. Yang. Symmetry breaking in Bose-Einstein condensates / M. Ueda. Quantized vortices in atomic Bose-Einstein condensates / M. Tsubota. Quantum degenerate gases of Ytterbium atoms / S. Uetake ... [et al.]. Superfluid properties of an ultracold fermi gas in the BCS-BEC crossover region / Y. Ohashi, N. Fukushima. Fermionic superfluidity and the BEC-BCS crossover in ultracold atomic fermi gases / M. W. Zwierlein. Kibble-Zurek mechanism in magnetization of a spinor Bose-Einstein condensate / H. Saito, Y. Kawaguchi, M. Ueda. Quasiparticle inducing Josephson effect in a Bose-Einstein condensate / S. Tsuchiya, Y. Ohashi. Stability of superfluid fermi gases in optical lattices / Y. Yunomae ... [et al.]. Z[symbol] symmetry breaking in multi-band bosonic atoms confined by a two-dimensional harmonic potential / M. Sato, A. Tokuno -- Spin hall effect and anomalous hall effect. Recent advances in anomalous hall effect and spin hall effect / N. Nagaosa. Topological insulators and the quantum spin hall effect / C. L. Kane. Application of direct and inverse spin-hall effects: electric manipulation of spin relaxation and electric detection of spin currents / K. Ando, E. Saitoh. Novel current pumping mechanism by spin dynamics / A. Takeuchi, K. Hosono, G. Tatara. Quantum spin hall phase in bismuth ultrathin film / S. Murakami. Anomalous hall effect due to the vector chirality / K. Taguchi, G. Tatara. Spin current distributions and spin hall effect in nonlocal magnetic nanostructures / R. Sugano ... [et al.]. New boundary critical phenomenon at the metal-quantum spin hall insulator transition / H. Obuse. On scaling behaviors of anomalous hall conductivity in disordered ferromagnets studied with the coherent potential approximation / S. Onoda -- Magnetic domain wall dynamics and spin related

  11. Helmholtz international Summer school quantum field theory at the limits. From strong fields to heavy quarks (HQ 2016). Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Ahmed; Blaschke, David; Issadykov, Aidos; Ivanov, Mikhail (eds.)

    2017-04-15

    The Helmholtz International Summer School (HISS) entitled ''Quantum Field Theory at the Limits: from Strong Fields to Heavy Quarks (SF→HQ)'', was held in the period July 18-30, 2016 at the Bogolyubov Laboratory of Theoretical Physics (BLTP) of the Joint Institute for Nuclear Research (JINR) in Dubna, Russia, as part of the activities of the Dubna International Advanced School of Theoretical Physics (DIAS-TH). It was co-organized by Ahmed Ali (DESY Hamburg), David Blaschke (JINR Dubna, MEPhI and Univ. Wroclaw), Holger Gies (HI Jena), and Mikhail Ivanov (JINR Dubna), and was attended by 82 participants (faculty+students), not counting the JINR physicists who attended some lectures as non-registered participants. The school (SF→HQ) continued the workshops and schools of the HISS series held earlier in Dubna (1993, 1996, 2000, 2005, 2008, 2013), Bad Honnef (1994) and Rostock (1997). The scientific program of the school consisted of five regular (one-hour long) lectures in the morning and afternoon sessions, with typically two contributed talks given by younger participants (students and postdocs), each half-hour long, in the late afternoons. Altogether, we had sixty lectures by the faculty and participants. In addition, black-board exercises were held in the post-lunch periods on selected aspects of strong fields and field theory. The HISS series of schools has played an important role in bringing together an international faculty and young physicists (Ph.D. and postdocs), mostly from Russia and Germany, but increasingly also from other countries, including those affiliated to JINR Dubna. They participate in two-week long intense scientific discourse, mainly dedicated lectures on selected topics covering the foundation and the frontiers of high energy physics and cosmology. The novelty of this year's school was its bifocal interest, which brought together two different physical science communities - particle and laser physicists. There were

  12. Helmholtz international Summer school quantum field theory at the limits. From strong fields to heavy quarks (HQ 2016). Proceedings

    International Nuclear Information System (INIS)

    Ali, Ahmed; Blaschke, David; Issadykov, Aidos; Ivanov, Mikhail

    2017-04-01

    The Helmholtz International Summer School (HISS) entitled ''Quantum Field Theory at the Limits: from Strong Fields to Heavy Quarks (SF→HQ)'', was held in the period July 18-30, 2016 at the Bogolyubov Laboratory of Theoretical Physics (BLTP) of the Joint Institute for Nuclear Research (JINR) in Dubna, Russia, as part of the activities of the Dubna International Advanced School of Theoretical Physics (DIAS-TH). It was co-organized by Ahmed Ali (DESY Hamburg), David Blaschke (JINR Dubna, MEPhI and Univ. Wroclaw), Holger Gies (HI Jena), and Mikhail Ivanov (JINR Dubna), and was attended by 82 participants (faculty+students), not counting the JINR physicists who attended some lectures as non-registered participants. The school (SF→HQ) continued the workshops and schools of the HISS series held earlier in Dubna (1993, 1996, 2000, 2005, 2008, 2013), Bad Honnef (1994) and Rostock (1997). The scientific program of the school consisted of five regular (one-hour long) lectures in the morning and afternoon sessions, with typically two contributed talks given by younger participants (students and postdocs), each half-hour long, in the late afternoons. Altogether, we had sixty lectures by the faculty and participants. In addition, black-board exercises were held in the post-lunch periods on selected aspects of strong fields and field theory. The HISS series of schools has played an important role in bringing together an international faculty and young physicists (Ph.D. and postdocs), mostly from Russia and Germany, but increasingly also from other countries, including those affiliated to JINR Dubna. They participate in two-week long intense scientific discourse, mainly dedicated lectures on selected topics covering the foundation and the frontiers of high energy physics and cosmology. The novelty of this year's school was its bifocal interest, which brought together two different physical science communities - particle and laser physicists. There were

  13. Generalized quantum groups

    International Nuclear Information System (INIS)

    Leivo, H.P.

    1992-01-01

    The algebraic approach to quantum groups is generalized to include what may be called an anyonic symmetry, reflecting the appearance of phases more general than ±1 under transposition. (author). 6 refs

  14. A tool for clinical reasoning and reflection using the international classification of functioning, disability and health (ICF) framework and patient management model.

    Science.gov (United States)

    Atkinson, Heather L; Nixon-Cave, Kim

    2011-03-01

    Professional development is a cornerstone of physical therapist practice. As the profession moves toward the ideals of Vision 2020, more emphasis is being placed on the process of clinical decision making. Although reflection and mentorship are widely regarded as important instruments to facilitate the progression of clinical reasoning skills, little guidance exists in the postprofessional arena to assist clinicians with these essential needs. As more organizations develop formal mentoring programs, a need arises for a tool that will engage mentors, protégés, and clinicians of all abilities in thoughtful reflection and discussion that will help develop clinical reasoning skills. The process of developing reflective clinical decision-making skills in physical therapist practitioners is described, and how this process was used at one institution is illustrated. A tool for clinical reasoning and reflection is proposed that incorporates the existing conceptual frameworks of the Guide to Physical Therapist Practice and the International Classification of Functioning, Disability and Health (ICF). This case report discusses how the tool was implemented by staff with varying levels of expertise, their outcomes in regard to the development of their clinical reasoning skills, and how the tool facilitated mentoring sessions around patient cases to improve care. This case report describes a practical application of a postprofessional educational process designed to develop reflective and patient-centered clinical reasoning skills. Although this process has shown some preliminary success, more research is warranted. By cultivating reflective thinking and critical inquiry, the physical therapy profession can help develop autonomous practitioners of physical therapy and promote the ideals of Vision 2020.

  15. Proceedings of the 8th International Symposium on Foundations of Quantum Mechanics in the Light of New Technology

    Science.gov (United States)

    Ishioka, Sachio; Fujikawa, Kazuo

    2006-06-01

    Preface -- Committees -- Opening address / H. Fukuyama -- Welcoming address / N. Osakabe -- Special lecture. Albert Einstein: opportunity and perception / C. N. Yang -- Quantum information and entanglement. Quantum optics with single atoms and photons / H. J. Kimble. Quantum information system experiments using a single photon source / Y. Yamamoto. Quantum communication and quantum computation with entangled photons / A. Zeilinger. High-fidelity quantum teleportation and a quantum teleportation network for continuous variables / N. Takei, A. Furusawa. Long lived entangled states / H. Häffner ... [et al.]. Quantum non-locality using tripartite entanglement with non-orthogonal states / J. V. Corbett, D. Home. Quantum entanglement and wedge product / H Heydari. Analysis of the generation of photon pairs in periodically poled lithium niobate / J. Söderholm ... [et al.]. Generation of entangled photons in a semiconductor and violation of Bell's inequality / G. Oohata, R. Shimizu, K. Edamatsu -- Quantum computing. Decoherence of a Josephson junction flux qubit / Y. Nakamura ... [et al.]. Spectroscopic analysis of a candidate two-qubit silicon quantum computer in the microwave regime / J. Gorman, D. G. Hasko, D. A. Williams. Berry phase detection in charge-coupled flux-qubits and the effect of decoherence / H. Nakano ... [et al.]. Locally observable conditions for the successful implementation of entangling multi-qubit quantum gates / H. F. Hofmann, R. Okamoto, S. Takeuchi. State control in flux qubit circuits: manipulating optical selection rules of microwave-assisted transitions in three-level artificial atoms / Y.-X. Liu ... [et al.]. The effect of local structure and non-uniformity on decoherence-free states of charge qubits / T. Tanamoto, S. Fujita. Entanglement-assisted estimation of quantum channels / A. Fujiwara. Superconducting quantum bit with ferromagnetic [symbol]-Junction / T. Yamashita, S. Takahashi, S. Maekawa. Generation of macroscopic Greenberger

  16. Quantum phase transition with dissipative frustration

    Science.gov (United States)

    Maile, D.; Andergassen, S.; Belzig, W.; Rastelli, G.

    2018-04-01

    We study the quantum phase transition of the one-dimensional phase model in the presence of dissipative frustration, provided by an interaction of the system with the environment through two noncommuting operators. Such a model can be realized in Josephson junction chains with shunt resistances and resistances between the chain and the ground. Using a self-consistent harmonic approximation, we determine the phase diagram at zero temperature which exhibits a quantum phase transition between an ordered phase, corresponding to the superconducting state, and a disordered phase, corresponding to the insulating state with localized superconducting charge. Interestingly, we find that the critical line separating the two phases has a nonmonotonic behavior as a function of the dissipative coupling strength. This result is a consequence of the frustration between (i) one dissipative coupling that quenches the quantum phase fluctuations favoring the ordered phase and (ii) one that quenches the quantum momentum (charge) fluctuations leading to a vanishing phase coherence. Moreover, within the self-consistent harmonic approximation, we analyze the dissipation induced crossover between a first and second order phase transition, showing that quantum frustration increases the range in which the phase transition is second order. The nonmonotonic behavior is reflected also in the purity of the system that quantifies the degree of correlation between the system and the environment, and in the logarithmic negativity as an entanglement measure that encodes the internal quantum correlations in the chain.

  17. Evaluation of carrier collection probability in bifacial interdigitated-back-contact crystalline silicon solar cells by the internal quantum efficiency mapping method

    Science.gov (United States)

    Tachibana, Tomihisa; Tanahashi, Katsuto; Mochizuki, Toshimitsu; Shirasawa, Katsuhiko; Takato, Hidetaka

    2018-04-01

    Bifacial interdigitated-back-contact (IBC) silicon solar cells with a high bifaciality of 0.91 were fabricated. Screen printing and firing technology were used to reduce the production cost. For the first time, the relationship between the rear side structure and carrier collection probability was evaluated using internal quantum efficiency (IQE) mapping. The measurement results showed that the screen-printed electrode and back surface field (BSF) area led to low IQE. The low carrier collection probability by BSF area can be explained by electrical shading effects. Thus, it is clear that the IQE mapping system is useful to evaluate the IBC cell.

  18. Maximising Intercultural Learning in Short Term International Placements: Findings Associated with Orientation Programs, Guided Reflection and Immersion

    Science.gov (United States)

    Campbell, Coral J. L.; Walta, Caroline

    2015-01-01

    Short-term international practicum experience is now a feature of many university education programs in Australia in an attempt to engage students with the growing multi-cultural aspects of Australian life. The stated purposes of such practicum experiences generally highlight intercultural learning, which is associated with the development of…

  19. Standard Setting for Next Generation TOEFL Academic Speaking Test (TAST): Reflections on the ETS Panel of International Teaching Assistant Developers

    Science.gov (United States)

    Papajohn, Dean

    2006-01-01

    While many institutions have utilized TOEFL scores for international admissions for many years, a speaking section has never before been a required part of TOEFL until the development of the iBT/Next Generation TOEFL. So institutions will need to determine how to set standards for the speaking section of TOEFL, also known as TOEFL Academic…

  20. Capacity Building in Southern Africa: Experiences and Reflections--Towards Joint Knowledge Production and Social Change in International Development Cooperation

    Science.gov (United States)

    Zeelen, Jacques; van der Linden, Josje

    2009-01-01

    The intent of capacity building in international development cooperation is to enable people to control their own development. Important premises are ownership, choice and self-esteem. The authors analyse the dynamics of the enabling process in practice, based on their own experiences working for several years in universities in developing…

  1. InAs/GaAs quantum dot structures covered by InGaAs strain reducing layer characterized by photomodulated reflectance

    Czech Academy of Sciences Publication Activity Database

    Hazdra, P.; Oswald, Jiří; Atef, M.; Kuldová, Karla; Hospodková, Alice; Hulicius, Eduard; Pangrác, Jiří

    2008-01-01

    Roč. 147, - (2008), s. 175-178 ISSN 0921-5107 R&D Projects: GA AV ČR IAA100100719; GA AV ČR KJB101630601; GA ČR GA202/06/0718 Institutional research plan: CEZ:AV0Z10100521 Keywords : optical properties * MOVPE * indium arsenide * gallium arsenide * quantum dots Subject RIV: BM - Solid Matter Physics ; Magnetism

  2. Reflective practice and social responsibility in family medicine: Effect of performing an international rotation in a developing country.

    Science.gov (United States)

    Loignon, Christine; Gottin, Thomas; Valois, Carol; Couturier, François; Williams, Robert; Roy, Pierre-Michel

    2016-11-01

    To explore the perceived effect of an elective international health rotation on family medicine resident learning. Qualitative, collaborative study based on semistructured interviews. Quebec. A sample of 12 family medicine residents and 9 rotation supervisors (N = 21). Semistructured interviews of residents and rotation supervisors. Residents and supervisors alike reported that their technical skills and relationship skills had benefited. All increased their knowledge of tropical pathologies and learned to expand their clinical examinations. They benefited from having very rich interactions in other care settings, working with vulnerable populations. The rotations had their greatest effect on relationship skills (communication, empathy, etc) and the ability to work with vulnerable patients. All of the participants were exposed to local therapies and local interpretations of disease symptoms and pathogenesis. The findings of this study will have a considerable effect on pedagogy. The residents' experiences of their international health rotations and what they learned in terms of medical skills and pedagogic approaches in working with patients are described. Using a collaborative approach with the rotation supervisors, the data were triangulated and the benefits of an international rotation on academic training were more accurately defined. The findings can now be used to enrich academic programs in social and preventive medicine and more adequately prepare future family physicians for work in various social and cultural settings. Copyright© the College of Family Physicians of Canada.

  3. Use of total internal reflection Raman (TIR) and attenuated total reflection infrared (ATR-IR) spectroscopy to analyze component separation in thin offset ink films after setting on coated paper surfaces.

    Science.gov (United States)

    Kivioja, Antti; Hartus, Timo; Vuorinen, Tapani; Gane, Patrick; Jääskeläinen, Anna-Stiina

    2013-06-01

    The interactive behavior of ink constituents with porous substrates during and after the offset print process has an important effect on the quality of printed products. To help elucidate the distribution of ink components between the retained ink layer and the substrate, a variety of spectroscopic and microscopic analysis techniques have been developed. This paper describes for the first time the use of total internal reflection (TIR) Raman spectroscopy to analyze the penetration behavior of separated offset ink components (linseed oil, solid color pigment) in coated papers providing chemically intrinsic information rapidly, nondestructively, and with minimal sample preparation. In addition, the already widely applied technique of attenuated total reflection infrared spectroscopy (ATR-IR) was evaluated in parallel and compared. The results of the ATR-IR Raman clearly revealed an improvement in uppermost depth resolution compared with values previously published from other nondestructive techniques, and the method is shown to be capable of providing new knowledge of the setting of thin (0.25-2 μm) offset ink films, allowing the spreading and the penetration behavior on physically different paper coating surfaces to be studied.

  4. Reduction of the internal electric field in GaN/AlN quantum dots grown on the a-plane of SiC substrates

    Energy Technology Data Exchange (ETDEWEB)

    Garro, N.; Cros, A.; Budagosky, J.A.; Cantarero, A. [Institut de Ciencia dels Materials, Universitat de Valencia, 46071 Valencia (Spain); Vinattieri, A.; Gurioli, M. [INFM, Dept. of Physics and LENS, Universita di Firenze, Via Sansone 1, 50019 Sesto Fiorentino (Italy); Founta, S.; Mariette, H.; Daudin, B. [CEA-CNRS Group ' ' Nanophysique et Semiconducteurs' ' , Departement de Recherche Fondamentale sur la Matiere Condensee, CEA Grenoble, 17 rue des Martyrs, 38054 Grenoble (France)

    2005-11-01

    We present a study of the emission of a multi-layer stack of self-assembled GaN/AlN quantum dots grown on the a-plane of 6H-SiC. We look for signatures of the internal electric field in the power dependence of the time-integrated and time-resolved photoluminescence spectra. The lack of a dynamical red-shift reveals that internal electric fields are significantly reduced in these dots. A band on the low energy side of the emission is observed whose intensity quenches fast when increasing the temperature. The polarization selection rules of the emission are examined in order to determine the physical nature of this band. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  5. Reflecting reflection in supervision

    DEFF Research Database (Denmark)

    Lystbæk, Christian Tang

    Reflection has moved from the margins to the mainstream in supervision. Notions of reflection have become well established since the late 1980s. These notions have provided useful framing devices to help conceptualize some important processes in guidance and counseling. However, some applications...... of these notions have distorted their original connotations and taken an excessively instrumentalistic and individualistic approach to their use. This paper will argue that we are, in the 2000s, seeing a questioning of an overly instrumentalistic and individualistic view of learning and development previously...... associated with reflection and an exploration of alternative conceptions that view reflection within the context of settings which have a more group- and team-based orientation. Drawing on an action research project on health care supervision, the paper questions whether we should reject earlier views...

  6. Three-dimensional particle tracking in concave structures made by ultraviolet nanoimprint via total internal reflection fluorescence microscopy and refractive-index-matching method

    Science.gov (United States)

    Fujinami, Taku; Kigami, Hiroshi; Unno, Noriyuki; Taniguchi, Jun; Satake, Shin-ichi

    2018-03-01

    Total internal reflection fluorescence microscopy (TIRFM) is a promising method for measuring fluid flow close to a wall with nanoscale resolution in a process that is termed "multilayer nanoparticle image velocimetry" (MnPIV). TIRFM uses evanescent light that is generated on a substrate (typically a glass slide) by total internal reflection of light. Many researchers have previously studied x-y-z (3D) flows of water close to flat glass slides using MnPIV. On the other hand, a fluid flow close to a structured surface is also important. To measure flows of water near micro-patterns, we previously developed an MnPIV technique that uses a refractive-index-matching method. In previous study, the micropattern is made of a thermoplastic material with a refractive index that closely matches that of water. In this study, ultraviolet nanoimprint lithography was used for fabricating the appropriate micro-patterns because this technique can fabricate a pattern with a high resolution. As a result, we succeeded in performing MnPIV in water with a circular hole array pattern made by ultraviolet nanoimprint using a refractive-index-matching method. We believe that this technique will be helpful in elucidating fluid flows around microstructures.

  7. Enhanced sensitivity to dielectric function and thickness of absorbing thin films by combining total internal reflection ellipsometry with standard ellipsometry and reflectometry

    International Nuclear Information System (INIS)

    Lizana, A; Foldyna, M; Garcia-Caurel, E; Stchakovsky, M; Georges, B; Nicolas, D

    2013-01-01

    High sensitivity of spectroscopic ellipsometry and reflectometry for the characterization of thin films can strongly decrease when layers, typically metals, absorb a significant fraction of the light. In this paper, we propose a solution to overcome this drawback using total internal reflection ellipsometry (TIRE) and exciting a surface longitudinal wave: a plasmon-polariton. As in the attenuated total reflectance technique, TIRE exploits a minimum in the intensity of reflected transversal magnetic (TM) polarized light and enhances the sensitivity of standard methods to thicknesses of absorbing films. Samples under study were stacks of three films, ZnO : Al/Ag/ZnO : Al, deposited on glass substrates. The thickness of the silver layer varied from sample to sample. We performed measurements with a UV–visible phase-modulated ellipsometer, an IR Mueller ellipsometer and a UV–NIR reflectometer. We used the variance–covariance formalism to evaluate the sensitivity of the ellipsometric data to different parameters of the optical model. Results have shown that using TIRE doubled the sensitivity to the silver layer thickness when compared with the standard ellipsometry. Moreover, the thickness of the ZnO : Al layer below the silver layer can be reliably quantified, unlike for the fit of the standard ellipsometry data, which is limited by the absorption of the silver layer. (paper)

  8. Social assistance and disability in Brazil: the reflection of the international debate of the rights of people with disability

    Directory of Open Access Journals (Sweden)

    Wederson Rufino dos Santos

    2010-07-01

    Full Text Available This paper reviews the debate on the social model of disability has influenced conceptions of the International Classification of Functioning, Disability and Health adopted by the World Health Organization in 2001 and adopted in Brazil in 2007, through the law of the Continuous Cash Benefit. The BPC is a major social policy of income transfer to poor disabled people, affecting over one million and half disabled people in the country. Since 2009, the evaluation of persons with disabilities for the BPC will make by medical and social skills targeted by ICF. Will be demonstrated that, although the adoption of the ICF maybe to represent regard to how to understand disability as social inequality, the adoption of the ICF by the law of the BPC will face challenges in ensuring the right to dignity of disabled people.

  9. Growth curves and the international standard: How children's growth reflects challenging conditions in rural Timor-Leste.

    Science.gov (United States)

    Spencer, Phoebe R; Sanders, Katherine A; Judge, Debra S

    2018-02-01

    Population-specific growth references are important in understanding local growth variation, especially in developing countries where child growth is poor and the need for effective health interventions is high. In this article, we use mixed longitudinal data to calculate the first growth curves for rural East Timorese children to identify where, during development, deviation from the international standards occurs. Over an eight-year period, 1,245 children from two ecologically distinct rural areas of Timor-Leste were measured a total of 4,904 times. We compared growth to the World Health Organization (WHO) standards using z-scores, and modeled height and weight velocity using the SuperImposition by Translation And Rotation (SITAR) method. Using the Generalized Additive Model for Location, Scale and Shape (GAMLSS) method, we created the first growth curves for rural Timorese children for height, weight and body mass index (BMI). Relative to the WHO standards, children show early-life growth faltering, and stunting throughout childhood and adolescence. The median height and weight for this population tracks below the WHO fifth centile. Males have poorer growth than females in both z-BMI (p = .001) and z-height-for-age (p = .018) and, unlike females, continue to grow into adulthood. This is the most comprehensive investigation to date of rural Timorese children's growth, and the growth curves created may potentially be used to identify future secular trends in growth as the country develops. We show significant deviation from the international standard that becomes most pronounced at adolescence, similar to the growth of other Asian populations. Males and females show different growth responses to challenging conditions in this population. © 2017 Wiley Periodicals, Inc.

  10. Internal Marketing and Reflective Subjects Formation Marketing Interno e a Formação de Sujeitos Reflexivos

    Directory of Open Access Journals (Sweden)

    Sérgio Carvalho Benício de Mello

    2011-03-01

    Full Text Available Internal marketing perspective has gaining primordial space. It happens through an interdisciplinary process with human management discipline and is based on the assumption that a significant part of the organizational success depends on the attitudes, commitment and performance of people in an organization, above all the ones that interact with the customers. Assuming the premise that such procedure depends on the relationship between the contact employees and the customers of an organization, we revise in this essay fundamental notions of interpresonel relationships to discuss the role of the internal marketing in the formation of employees that becomes reflexive subjects. We understand such premise as a fundamental characteristic for those to carry out his/her role in a conscious way. Our conclusion is a theoretical proposal of how this can be developed.A perspectiva do marketing interno tem ganho espaço primordial. Isto ocorre por meio de um processo interdisciplinar com a gestão de pessoas, por se compreender que parte do êxito organizacional dependa das atitudes, do comprometimento e do desempenho de todos os envolvidos numa organização, sobretudo os que interagem com os clientes. Assumindo a premissa de que tal procedimento dependa do relacionamento entre o funcionário de contato e os clientes de uma organização, neste ensaio teórico revisamos noções fundamentais do conhecimento acerca das relações interpessoais para discutir o papel do marketing interno na formação de funcionários que se tornem sujeitos reflexivos. Tal premissa é por nos compreendida como característica fundamental para que estes desempenhem seu papel de forma consciente. Nossa chegada é uma proposta teórica de como isto possa ser desenvolvido.

  11. Effects of a strong magnetic field on internal gravity waves: trapping, phase mixing, reflection and dynamical chaos

    Science.gov (United States)

    Loi, Shyeh Tjing; Papaloizou, John C. B.

    2018-04-01

    The spectrum of oscillation modes of a star provides information not only about its material properties (e.g. mean density), but also its symmetries. Spherical symmetry can be broken by rotation and/or magnetic fields. It has been postulated that strong magnetic fields in the cores of some red giants are responsible for their anomalously weak dipole mode amplitudes (the "dipole dichotomy" problem), but a detailed understanding of how gravity waves interact with strong fields is thus far lacking. In this work, we attack the problem through a variety of analytical and numerical techniques, applied to a localised region centred on a null line of a confined axisymmetric magnetic field which is approximated as being cylindrically symmetric. We uncover a rich variety of phenomena that manifest when the field strength exceeds a critical value, beyond which the symmetry is drastically broken by the Lorentz force. When this threshold is reached, the spatial structure of the g-modes becomes heavily altered. The dynamics of wave packet propagation transitions from regular to chaotic, which is expected to fundamentally change the organisation of the mode spectrum. In addition, depending on their frequency and the orientation of field lines with respect to the stratification, waves impinging on different parts of the magnetised region are found to undergo either reflection or trapping. Trapping regions provide an avenue for energy loss through Alfvén wave phase mixing. Our results may find application in various astrophysical contexts, including the dipole dichotomy problem, the solar interior, and compact star oscillations.

  12. Reflections on nuclear challenges today. 6 December 2005, London, UK, International Institute for Strategic Studies, Allistair Buchan Lecture

    International Nuclear Information System (INIS)

    ElBaradei, M.

    2005-01-01

    Emerging nuclear challenges are proliferation of nuclear weapons and sensitive nuclear technologies, emergence of nuclear clandestine procurement networks in nuclear materials and equipment and the sluggishment in nuclear disarmament. Practical steps to address them are 1) better control of access to nuclear fuel cycle technology; 2) supporting effective nuclear verification; 3) strengthening the credibility of enforcement mechanisms; 4) protecting nuclear material and 5) developing an alternative approach to collective security. For better control of access to nuclear fuel cycle technology a group of international experts proposes to a) provide assurance of supply of reactor technology and nuclear fuel; b) accept a time-limited moratorium (of perhaps 5-10 years) on new uranium enrichment and plutonium separation facilities - at the very least for countries that do not currently have such technologies; c) establish a framework for multilateral management and control of the 'back end' of the fuel cycle (i.e. spent fuel reprocessing and waste disposal); and d) create a similar framework for multilateral management and control of the 'front end' of the fuel cycle (i.e. enrichment and fuel production). The effectiveness of nuclear verification depends on the extend of access to information and locations in a given country and inspections can only verify what countries declare. The expanded access provided by the Additional Protocol to safeguards agreements enables the Agency to verify possible undeclared activities however both safeguards agreements are focused on nuclear material and therefore the Agency's authority to investigate possible parallel weaponization activity is limited. In addition only 70 countries have the additional protocol on force. A dditional transparency measures' may be required as well as additional funding to support R and D on new technologies for detecting clandestine nuclear facilities and activity. An important step to address the nuclear

  13. "Contagion" between the emerging and developed capital markets: empirical evidence and reflections on the international portfolio diversification

    Directory of Open Access Journals (Sweden)

    Wagner Moura Lamounier

    2008-10-01

    Full Text Available In this research, we analyzed the short and long term interdependence and relationship between the stock indices of the major emerging capital markets and the major developed markets for the period 1995-2005. The aim was to verify the existence and the dynamics of the “contagion” between the markets, or if the occurrence of crises and changes in the behavior of a market would have impacts on the behavior of the others. In the development of the work, we applied the methodology of the Vector Error Correction Model (VEC. We found the presence of cointegrating relationships between the markets analyzed, but was able to see that, despite being cointegrated markets, investors could benefit from international diversification of portfolios. That’s because the speed of adjustment of the long-term ratio of cointegration between the markets was low for the period analyzed. Accordingly, investors would have the opportunity to reduce risk by diversifying their portfolios.

  14. An Action Research into International Masters Program in Practicing Management (IMPM: Suggesting Refraction to Complement Reflection for Management Learning in the Global Knowledge Economy

    Directory of Open Access Journals (Sweden)

    Tunc D. MEDENI

    2008-05-01

    Full Text Available International Masters Program in Practicing Management (IMPM is a collaborative effort by major business schools and corporations around the world, balancing practical and academic issues within pedagogy of “experienced reflection”. This action research into the IMPM aims to explain the IMPM and its importance for the global knowledge economy, as well as identify and improve the current limitations of the program. As a result, we hope to provide specific suggestions for the IMPM practice and general guidelines for business education. Our suggestions are based upon a framework of “refraction” that follows a methodology of action research and pluralistic knowledge science epistemology, a critique of management learning, and a literature review on (critical reflection, as well as our findings about the IMPM practice. Also, critically reviewing Mintzberg and other authors’ ideas on management learning and IMPM specifically supports our discussion in this paper.

  15. Total internal reflection quasiphase matching-based broadband second harmonic generation in a plane-parallel uniaxial crystal of lithium niobate

    Science.gov (United States)

    Barma, Minakshi Deb; Deb, Sumita; Saha, Ardhendu

    2018-01-01

    The present work analytically investigates the generation of broadband second harmonic (SH) using total internal reflection (TIR) quasiphase matching technique in a plane-parallel uniaxial crystal having optic axis nonparallel with respect to the horizontal base. A computer-aided simulation has been performed using lithium niobate as the nonlinear material to determine the possibility of generating broadband SH intensity when broadband fundamental laser radiation is allowed to undergo TIR inside the crystal. The simulated results indicate a peak conversion efficiency of 5.22% with a spectral bandwidth (BW) of 116 nm, centered at 2.258 μm in a 10-mm-long slab. The effect of variation in operating temperature, crystal length, crystal thickness, angle of deviation of optic axis, and angle of incidence of fundamental beam at the air-prism interface on efficiency and BW of resulting SH output has been studied.

  16. Imaging exocytosis of single glucagon-like peptide-1 containing granules in a murine enteroendocrine cell line with total internal reflection fluorescent microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ohara-Imaizumi, Mica; Aoyagi, Kyota [Department of Biochemistry, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181-8611 (Japan); Akimoto, Yoshihiro [Department of Anatomy, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181-8611 (Japan); Nakamichi, Yoko; Nishiwaki, Chiyono [Department of Biochemistry, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181-8611 (Japan); Kawakami, Hayato [Department of Anatomy, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181-8611 (Japan); Nagamatsu, Shinya, E-mail: shinya@ks.kyorin-u.ac.jp [Department of Biochemistry, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181-8611 (Japan)

    2009-12-04

    To analyze the exocytosis of glucagon-like peptide-1 (GLP-1) granules, we imaged the motion of GLP-1 granules labeled with enhanced yellow fluorescent protein (Venus) fused to human growth hormone (hGH-Venus) in an enteroendocrine cell line, STC-1 cells, by total internal reflection fluorescent (TIRF) microscopy. We found glucose stimulation caused biphasic GLP-1 granule exocytosis: during the first phase, fusion events occurred from two types of granules (previously docked granules and newcomers), and thereafter continuous fusion was observed mostly from newcomers during the second phase. Closely similar to the insulin granule fusion from pancreatic {beta} cells, the regulated biphasic exocytosis from two types of granules may be a common mechanism in glucose-evoked hormone release from endocrine cells.

  17. Creative scientific research international session of 2nd meeting on advanced pulsed-neutron research on quantum functions in nano-scale materials

    International Nuclear Information System (INIS)

    Itoh, Shinichi

    2005-06-01

    1 MW-class pulsed-neutron sources will be constructed in Japan, United State and United Kingdom in a few years. Now is the time for a challenge to innovate on neutron science and extend new science fields. Toward the new era, we develop new pulsed-neutron technologies as well as new neutron devices under the international collaborations with existing pulsed-neutron facilities, such as the UK-Japan collaboration program on neutron scattering. At the same time, the new era will bring international competitions to neutron researchers. We aim to create new neutron science toward the new pulsed-neutron era by introducing the new technologies developed here. For this purpose, we have started the research project, 'Advanced pulsed-neutron research on quantum functions in nano-scale materials,' in the duration between JFY2004 and JFY2008. The 2nd meeting of this project was held on 22-24 February 2005 to summarize activities in FY2004 and to propose research projects in the coming new fiscal year. In this international session as a part of this meeting, the scientific results and research plans on the UK-Japan collaboration program, the research plans on the collaboration between IPNS (Intense Pulsed Neutron Source, Argonne National Laboratory) and KENS (Neutron Science Laboratory, KEK), also the recent scientific results arisen form this project were presented. (author)

  18. Quantum dot imaging in the second near-infrared optical window: studies on reflectance fluorescence imaging depths by effective fluence rate and multiple image acquisition

    Science.gov (United States)

    Jung, Yebin; Jeong, Sanghwa; Nayoun, Won; Ahn, Boeun; Kwag, Jungheon; Geol Kim, Sang; Kim, Sungjee

    2015-04-01

    Quantum dot (QD) imaging capability was investigated by the imaging depth at a near-infrared second optical window (SOW; 1000 to 1400 nm) using time-modulated pulsed laser excitations to control the effective fluence rate. Various media, such as liquid phantoms, tissues, and in vivo small animals, were used and the imaging depths were compared with our predicted values. The QD imaging depth under excitation of continuous 20 mW/cm2 laser was determined to be 10.3 mm for 2 wt% hemoglobin phantom medium and 5.85 mm for 1 wt% intralipid phantom, which were extended by more than two times on increasing the effective fluence rate to 2000 mW/cm2. Bovine liver and porcine skin tissues also showed similar enhancement in the contrast-to-noise ratio (CNR) values. A QD sample was inserted into the abdomen of a mouse. With a higher effective fluence rate, the CNR increased more than twofold and the QD sample became clearly visualized, which was completely undetectable under continuous excitation. Multiple acquisitions of QD images and averaging process pixel by pixel were performed to overcome the thermal noise issue of the detector in SOW, which yielded significant enhancement in the imaging capability, showing up to a 1.5 times increase in the CNR.

  19. Quantum networks based on cavity QED

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, Stephan; Bochmann, Joerg; Figueroa, Eden; Hahn, Carolin; Kalb, Norbert; Muecke, Martin; Neuzner, Andreas; Noelleke, Christian; Reiserer, Andreas; Uphoff, Manuel; Rempe, Gerhard [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, 85748 Garching (Germany)

    2014-07-01

    Quantum repeaters require an efficient interface between stationary quantum memories and flying photons. Single atoms in optical cavities are ideally suited as universal quantum network nodes that are capable of sending, storing, retrieving, and even processing quantum information. We demonstrate this by presenting an elementary version of a quantum network based on two identical nodes in remote, independent laboratories. The reversible exchange of quantum information and the creation of remote entanglement are achieved by exchange of a single photon. Quantum teleportation is implemented using a time-resolved photonic Bell-state measurement. Quantum control over all degrees of freedom of the single atom also allows for the nondestructive detection of flying photons and the implementation of a quantum gate between the spin state of the atom and the polarization of a photon upon its reflection from the cavity. Our approach to quantum networking offers a clear perspective for scalability and provides the essential components for the realization of a quantum repeater.

  20. Quantum-dynamical Modeling of the Rydberg to Valence Excited-State Internal Conversion in Cyclobutanone and Cyclopentanone

    Directory of Open Access Journals (Sweden)

    Møller K. B.

    2013-03-01

    Full Text Available In this paper we present 4-state, 5-dimensional Vibronic Coupling Hamiltonians for cyclobutanone and cyclopentanone. Wave packet calculations using these Hamiltonians reveal that for cyclobutanone the (n,3s to (n,π* internal conversion involves direct motion in nuclear modes coupling the two states leading to fast population transfer. For cyclopentanone, internal vibrational energy redistribution is a bottleneck for activating reactive nuclear modes leading to slower population transfer.

  1. Quantum-dynamical Modeling of the Rydberg to Valence Excited-State Internal Conversion in Cyclobutanone and Cyclopentanone

    DEFF Research Database (Denmark)

    Kuhlman, T. S.; Sauer, Stephan P. A.; Solling, T. I.

    2013-01-01

    In this paper we present 4-state, 5-dimensional Vibronic Coupling Hamiltonians for cyclobutanone and cyclopentanone. Wave packet calculations using these Hamiltonians reveal that for cyclobutanone the (n,3s) to (n,π*) internal conversion involves direct motion in nuclear modes coupling the two st...... states leading to fast population transfer. For cyclopentanone, internal vibrational energy redistribution is a bottleneck for activating reactive nuclear modes leading to slower population transfer....

  2. Graphene quantum dots

    CERN Document Server

    Güçlü, Alev Devrim; Korkusinski, Marek; Hawrylak, Pawel

    2014-01-01

    This book reflects the current status of theoretical and experimental research of graphene based nanostructures, in particular quantum dots, at a level accessible to young researchers, graduate students, experimentalists and theorists. It presents the current state of research of graphene quantum dots, a single or few monolayer thick islands of graphene. It introduces the reader to the electronic and optical properties of graphite, intercalated graphite and graphene, including Dirac fermions, Berry's phase associated with sublattices and valley degeneracy, covers single particle properties of

  3. Quantum Optical Multiple Scattering

    DEFF Research Database (Denmark)

    Ott, Johan Raunkjær

    . In the first part we use a scattering-matrix formalism combined with results from random-matrix theory to investigate the interference of quantum optical states on a multiple scattering medium. We investigate a single realization of a scattering medium thereby showing that it is possible to create entangled...... states by interference of squeezed beams. Mixing photon states on the single realization also shows that quantum interference naturally arises by interfering quantum states. We further investigate the ensemble averaged transmission properties of the quantized light and see that the induced quantum...... interference survives even after disorder averaging. The quantum interference manifests itself through increased photon correlations. Furthermore, the theoretical description of a measurement procedure is presented. In this work we relate the noise power spectrum of the total transmitted or reflected light...

  4. Quantum walks, quantum gates, and quantum computers

    International Nuclear Information System (INIS)

    Hines, Andrew P.; Stamp, P. C. E.

    2007-01-01

    The physics of quantum walks on graphs is formulated in Hamiltonian language, both for simple quantum walks and for composite walks, where extra discrete degrees of freedom live at each node of the graph. It is shown how to map between quantum walk Hamiltonians and Hamiltonians for qubit systems and quantum circuits; this is done for both single-excitation and multiexcitation encodings. Specific examples of spin chains, as well as static and dynamic systems of qubits, are mapped to quantum walks, and walks on hyperlattices and hypercubes are mapped to various gate systems. We also show how to map a quantum circuit performing the quantum Fourier transform, the key element of Shor's algorithm, to a quantum walk system doing the same. The results herein are an essential preliminary to a Hamiltonian formulation of quantum walks in which coupling to a dynamic quantum environment is included

  5. PREFACE Quantum Groups, Quantum Foundations and Quantum Information: a Festschrift for Tony Sudbery

    Science.gov (United States)

    Weigert, Stefan

    2010-11-01

    On 29 July 2008, Professor Anthony Thomas Sudbery - known as Tony to his friends and colleagues - celebrated his 65th birthday. To mark this occasion and to honour Tony's scientific achievements, a 2-day Symposion was held at the University of York on 29-30 September 2008 under the sponsorship of the Institute of Physics and the London Mathematical Society. The breadth of Tony's research interests was reflected in the twelve invited lectures by A Beige, I Bengtsson, K Brown, N Cerf, E Corrigan, J Ladyman, A J Macfarlane, S Majid, C Manogue, S Popescu, J Ryan and R W Tucker. This Festschrift, also made possible by the generosity of the IOP and the LMS, reproduces the majority of these contributions together with other invited papers. Tony obtained his PhD from the University of Cambridge in 1970. His thesis, written under the guidance of Alan Macfarlane, is entitled Some aspects of chiral su(3) × su(3) symmetry in hadron dynamics. He arrived in York in 1971 with his wife Rodie, two young daughters, a lively mind and a very contemporary shock of hair. He was at that stage interested in mathematical physics and so was classed as an applied mathematician in the departmental division in place at that time. But luckily Tony did not fit into this category. His curiosity is combined with a good nose for problems and his capacity for knocking off conjectures impressed us all. Within a short time of his arrival he was writing papers on group theory, complex analysis and combinatorics, while continuing to work on quantum mechanics. His important paper on quaternionic analysis is an example of the imagination and elegance of his ideas. By developing a derivative, he replaced the relatively obscure analytical theory of quaternions by one informed by modern complex analysis. Other interests emerged, centred round the quantum: quantum mechanics and its foundations, quantum groups and quantum information. He didn't just dabble in these areas but mastered them, gaining a national

  6. PREFACE: International Conference on 'Quantum Control, Exact or Perturbative, Linear or Nonlinear' to celebrate 50 years of the scientific career of Professor Bogdan Mielnik (Mielnik50)

    Science.gov (United States)

    Bretón, N.; Fernández, D.; Kielanowski, P.

    2015-06-01

    The International Conference on 'Quantum Control, Exact or Perturbative, Linear or Nonlinear', took place in Mexico City on 22-24 October 2014. It was held with the aim of celebrating the first fifty years of scientific career of Bogdan Mielnik, an outstanding scientist whose professional trajectory spans over Poland and Mexico and who is currently Professor Emeritus in the Physics Department of Centro de Investigación y de Estudios Avanzados del IPN (Cinvestav) in Mexico. Bogdan Mielnik was born on May 6th, 1936 in Warsaw, Poland. He studied elementary and high school until 1953. In the autumn of 1953 he started the studies in the Faculty of Mathematics and Physics at the University of Warsaw, and at the end of 1957 he did his master work under the direction of Professor Jerzy Plebański. In 1962 he was invited to the newly opened Research Center of IPN (Cinvestav), in Mexico, as an assistant and PhD student of Jerzy Plebański. On October 22nd, 1964, he submitted to Cinvestav his PhD Thesis entitled ''Analytic functions of the displacement operator'', marking the offcial beginning of his scientific career. It is worth mentioning that Bogdan Mielnik is the first PhD graduate of the Physics Department of Cinvestav, so with this Conference our Department was also celebrating an important date on its calendar. A more detailed information can be found in the website http://www.fis.cinvestav.mx/mielnik50/. It was our great pleasure to see that many collaborators and former students of Bogdan Mielnik attended this Conference. The articles collected in this volume are the written contributions of the majority of talks presented at the conference. They have been organized according to the research subjects that Bogdan Mielnik has been involved in. Thus, the articles of JG Hirsch, L Hughston, G Morales-Luna, O Rosas-Ortiz and G Torres-Vega deal with Fundamental Problems in Quantum Mechanics. On the other hand, the papers by F Delgado, H Hernández-Coronado, G Herrera

  7. A simple method for migrating narrow aperture, noisy seismic reflection data and application to Project INDEPTH (International Deep Profiling of Tibet and the Himalaya) deep seismic profiles

    Science.gov (United States)

    Alsdorf, Doug

    1997-08-01

    Migration of deep seismic data is often hindered by a narrow recording aperture (line length by record length) and a low signal-to-noise ratio. The severity of typical migration artifacts (e.g., lateral smearing of discontinuous reflections into synforms, "smiles") increases with travel time such that interpreters of deep seismic data have often substituted migrated line drawings for the actual sections. As part of Project INDEPTH (International Deep Profiling of Tibet and the Himalaya), a new migration method was developed to address both the noise and migration issues. The method works in the time-space domain and uses the simple, constant velocity, straight ray path to perform the migration. First, only amplitudes within a given range are retained for migration, thus avoiding high-amplitude noise bursts and low-amplitude background noise. Then, the local dip of a reflection is found by automatically fitting a straight line to the highest amplitudes within a small window (several time samples by several traces) and calculating the dip of the line using a constant velocity. Finally, using this dip, the method migrates a selected amplitude value. The dips, lateral positions, and depths of the migrated events compare very well with output from more conventional algorithms (e.g.,fk-Stolt, finite difference, etc.). The advantages of the new method include fewer artifacts, fast computer run times, low memory use and the ability to migrate long profiles and travel times (e.g., 50 s). The output of the method is a grid of migrated amplitudes (not wavelets) or dip values which is particularly effective for making small figures, such as those needed for publication. The principal disadvantage is the use of a constant migration velocity.

  8. Quantum Squeezing

    International Nuclear Information System (INIS)

    Zubairy, Suhail

    2005-01-01

    Langevin formalism for squeezing in lasing systems. In the last article of this part, Wiseman deals with squeezing systems when the system's environment can be deliberately engineered so that the feedback is important. The third part of the book includes four articles dealing with the applications of quantum squeezing. In the first article, Yuen presents a discussion of communications and measurement using squeezed states and discusses the advantages of using nonclassical light over classical light in communications and measurement. In the second article, Swain deals with the interaction of squeezed light with the atomic systems and presents a review of novel phenomena in spectroscopy. This chapter on two-level atomic system is followed by Ficek's article on squeezed-light based spectroscopy in three-level atomic systems. In the last article, Reid again addresses the advantages of squeezed light in communications, but her emphasis is different from that of Yuen's article. Here she discusses EPR correlations for squeezed light and presents squeezed-light based methods for quantum cryptography. All the authors are leading figures in the field of squeezed states who have made pioneering contributions to various aspects of the field over the years. This is reflected in the authoritative style with which all the articles are written. These articles are rich in content, easy to read and cover a broad base. The emphasis is however on the theoretical aspects with occasional references to experimental work. This book is an excellent collection of articles on quantum squeezing that are highly useful both for beginners who would like to learn about squeezing and its applications, as well as for experts who would like to learn about the frontiers. (book review)

  9. Two Quantum Polytropic Cycles

    Science.gov (United States)

    Arias-Hernández, L. A.; Morales-Serrano, A. F.

    2002-11-01

    In this work we follow the Bender et al paper [1] to study the quantum analogues of the Stirling and Ericsson polytropic cycles. In the context of the classical thermodynamics, the Stirling and Ericsson cycles correspond to reversible heat engines with two isothermal processes joined by two polytropic branches which occur in a device called regenerator. If this device is an ideal one, the efficiency of these cycles is the Carnot efficiency. Here, we introduce the quantum analogues of the Stirling and Ericsson cycles, the first one based on a double square potential well with a finite potential barrier, since in this system the tunnel effect could be the analogue to the regeneration classical process, therefore the isochoric quantum branches would really correspond to an internal energy storage, and the last one with an unknown system where the isobaric quantum processes don't induce changes in its quantum state. With these systems the quantum engines have cycles consisting of polytropic and isothermal quantum processes analogues to the corresponding classical processes. We show that in both cases the quantum cycles have an efficiency given by ηCQM = 1 - EC/EH, which is the same expression for the quantum analogue of the Carnot cycle studied by Bender.

  10. Internal rotation potential and structure of six fluorine substituted nitrobenzenes studied by microwave spectroscopy supported by quantum chemical calculations

    DEFF Research Database (Denmark)

    Larsen, Niels Wessel; Nielsen, Ole Vesterlund

    2014-01-01

    Microwave spectra of the vibrational ground state and several torsionally excited states were used to investigate the internal rotation potential and the structure of six fluorine substituted nitrobenzenes: 3-fluoro- and 4-fluoronitrobenzene were planar molecules just as nitrobenzene whereas 2...

  11. Quantum correlations in semiconductor microcavities

    Science.gov (United States)

    Kira, M.; Hoyer, W.; Koch, S. W.; Brick, P.; Ell, C.; Hübner, M.; Khitrova, G.; Gibbs, H. M.

    2003-10-01

    The quantum mechanical nature of the light field in semiconductor microcavities leads to non-classical coupling effects between photons and electron-hole excitations. It is shown that these quantum correlations give rise to characteristic corrections of the semiclassical light-matter coupling dynamics. Examples of quantum correlation signatures include entanglement effects in the probe reflection of a microcavity system and squeezing in the incoherent emission.

  12. Quantum Multiverses

    OpenAIRE

    Hartle, James B.

    2018-01-01

    A quantum theory of the universe consists of a theory of its quantum dynamics and a theory of its quantum state The theory predicts quantum multiverses in the form of decoherent sets of alternative histories describing the evolution of the universe's spacetime geometry and matter content. These consequences follow: (a) The universe generally exhibits different quantum multiverses at different levels and kinds of coarse graining. (b) Quantum multiverses are not a choice or an assumption but ar...

  13. Quantum Imaging

    CERN Document Server

    Kolobov, Mikhail I

    2007-01-01

    Quantum Imaging is a newly born branch of quantum optics that investigates the ultimate performance limits of optical imaging allowed by the laws of quantum mechanics. Using the methods and techniques from quantum optics, quantum imaging addresses the questions of image formation, processing and detection with sensitivity and resolution exceeding the limits of classical imaging. This book contains the most important theoretical and experimental results achieved by the researchers of the Quantum Imaging network, a research programme of the European Community.

  14. Quantum Malware

    OpenAIRE

    Wu, Lian-Ao; Lidar, Daniel A.

    2005-01-01

    When quantum communication networks proliferate they will likely be subject to a new type of attack: by hackers, virus makers, and other malicious intruders. Here we introduce the concept of "quantum malware" to describe such human-made intrusions. We offer a simple solution for storage of quantum information in a manner which protects quantum networks from quantum malware. This solution involves swapping the quantum information at random times between the network and isolated, distributed an...

  15. Beyond quantum

    CERN Document Server

    Khrennikov, Andrei

    2014-01-01

    The present wave of interest in quantum foundations is caused by the tremendous development of quantum information science and its applications to quantum computing and quantum communication. It has become clear that some of the difficulties encountered in realizations of quantum information processing have roots at the very fundamental level. To solve such problems, quantum theory has to be reconsidered. This book is devoted to the analysis of the probabilistic structure of quantum theory, probing the limits of classical probabilistic representation of quantum phenomena.

  16. Living Systems are Dynamically Stable by Computing Themselves at the Quantum Level

    Science.gov (United States)

    Igamberdiev, Abir U.

    2003-06-01

    The smallest details of living systems are molecular devices that operate between the classical and quantum levels, i.e. between the potential dimension (microscale) and the actual three-dimensional space (macroscale). They realize non-demolition quantum measurements in which time appears as a mesoscale dimension separating contradictory statements in the course of actualization. These smaller devices form larger devices (macromolecular complexes), up to living body. The quantum device possesses its own potential internal quantum state (IQS), which is maintained for prolonged time via error-correction being a reflection over this state. Decoherence-free IQS can exhibit itself by a creative generation of iteration limits in the real world. To avoid a collapse of the quantum information in the process of correcting errors, it is possible to make a partial measurement that extracts only the error-information and leaves the encoded state untouched. In natural quantum computers, which are living systems, the error-correction is internal. It is a result of reflection, given as a sort of a subjective process allotting optimal limits of iteration. The IQS resembles the properties of a quasi-particle, which interacts with the surround, applying decoherence commands to it. In this framework, enzymes are molecular automata of the extremal quantum computer, the set of which maintains stable highly ordered coherent state, and genome represents a concatenation of error-correcting codes into a single reflective set. Biological systems, being autopoietic in physical space, control quantum measurements in the physical universe. The biological evolution is really a functional evolution of measurement constraints in which limits of iteration are established possessing criteria of perfection and having selective values.

  17. Living Systems are Dynamically Stable by Computing Themselves at the Quantum Level

    Directory of Open Access Journals (Sweden)

    Abir U. Igamberdiev

    2003-06-01

    Full Text Available Abstract: The smallest details of living systems are molecular devices that operate between the classical and quantum levels, i.e. between the potential dimension (microscale and the actual three-dimensional space (macroscale. They realize non-demolition quantum measurements in which time appears as a mesoscale dimension separating contradictory statements in the course of actualization. These smaller devices form larger devices (macromolecular complexes, up to living body. The quantum device possesses its own potential internal quantum state (IQS, which is maintained for prolonged time via error-correction being a reflection over this state. Decoherence-free IQS can exhibit itself by a creative generation of iteration limits in the real world. To avoid a collapse of the quantum information in the process of correcting errors, it is possible to make a partial measurement that extracts only the error-information and leaves the encoded state untouched. In natural quantum computers, which are living systems, the error-correction is internal. It is a result of reflection, given as a sort of a subjective process allotting optimal limits of iteration. The IQS resembles the properties of a quasi-particle, which interacts with the surround, applying decoherence commands to it. In this framework, enzymes are molecular automata of the extremal quantum computer, the set of which maintains stable highly ordered coherent state, and genome represents a concatenation of error-correcting codes into a single reflective set. Biological systems, being autopoietic in physical space, control quantum measurements in the physical universe. The biological evolution is really a functional evolution of measurement constraints in which limits of iteration are established possessing criteria of perfection and having selective values.

  18. Distribution of quantum information between an atom and two photons

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Bernhard

    2008-11-03

    The construction of networks consisting of optically interconnected processing units is a promising way to scale up quantum information processing systems. To store quantum information, single trapped atoms are among the most proven candidates. By placing them in high finesse optical resonators, a bidirectional information exchange between the atoms and photons becomes possible with, in principle, unit efficiency. Such an interface between stationary and ying qubits constitutes a possible node of a future quantum network. The results presented in this thesis demonstrate the prospects of a quantum interface consisting of a single atom trapped within the mode of a high-finesse optical cavity. In a two-step process, we distribute entanglement between the stored atom and two subsequently emitted single photons. The long atom trapping times achieved in the system together with the high photon collection efficiency of the cavity make the applied protocol in principle deterministic, allowing for the creation of an entangled state at the push of a button. Running the protocol on this quasi-stationary quantum interface, the internal state of the atom is entangled with the polarization state of a single emitted photon. The entanglement is generated by driving a vacuum-stimulated Raman adiabatic passage between states of the coupled atom-cavity system. In a second process, the atomic part of the entangled state is mapped onto a second emitted photon using a similar technique and resulting in a polarization-entangled two-photon state. To verify and characterize the photon-photon entanglement, we measured a violation of a Bell inequality and performed a full quantum state tomography. The results prove the prior atom-photon entanglement and demonstrate a quantum information transfer between the atom and the two emitted photons. This reflects the advantages of a high-finesse cavity as a quantum interface in future quantum networks. (orig.)

  19. Distribution of quantum information between an atom and two photons

    International Nuclear Information System (INIS)

    Weber, Bernhard

    2008-01-01

    The construction of networks consisting of optically interconnected processing units is a promising way to scale up quantum information processing systems. To store quantum information, single trapped atoms are among the most proven candidates. By placing them in high finesse optical resonators, a bidirectional information exchange between the atoms and photons becomes possible with, in principle, unit efficiency. Such an interface between stationary and ying qubits constitutes a possible node of a future quantum network. The results presented in this thesis demonstrate the prospects of a quantum interface consisting of a single atom trapped within the mode of a high-finesse optical cavity. In a two-step process, we distribute entanglement between the stored atom and two subsequently emitted single photons. The long atom trapping times achieved in the system together with the high photon collection efficiency of the cavity make the applied protocol in principle deterministic, allowing for the creation of an entangled state at the push of a button. Running the protocol on this quasi-stationary quantum interface, the internal state of the atom is entangled with the polarization state of a single emitted photon. The entanglement is generated by driving a vacuum-stimulated Raman adiabatic passage between states of the coupled atom-cavity system. In a second process, the atomic part of the entangled state is mapped onto a second emitted photon using a similar technique and resulting in a polarization-entangled two-photon state. To verify and characterize the photon-photon entanglement, we measured a violation of a Bell inequality and performed a full quantum state tomography. The results prove the prior atom-photon entanglement and demonstrate a quantum information transfer between the atom and the two emitted photons. This reflects the advantages of a high-finesse cavity as a quantum interface in future quantum networks. (orig.)

  20. Selected techniques in radioecology: Model development and comparison for internal dosimetry of rainbow trout (Oncorhynchus mykiss) and feasibiltiy assessment of reflectance spectroscopy use as a tool in phytoremediation

    Science.gov (United States)

    Martinez, Nicole

    The first study in Part 1 examines the effects of lake tropic structure on the uptake of iodine-131 (131I) in rainbow trout (Oncorhynchus mykiss) and considers a simple computational model for the estimation of resulting radiation dose. Iodine-131 is a major component of the atmospheric releases following reactor accidents, and the passage of 131I through food chains from grass to human thyroids has been extensively studied. By comparison, the fate and effects of 131I deposition onto lakes and other aquatic systems has been less studied. In this study we reanalyze 1960s data from experimental releases of 131I into two small lakes and compare the effects of differences in lake trophic structures on 131I accumulation in fish. The largest concentrations in the thyroids of trout may occur from 8 to 32 days post initial release. DCFs for trout for whole body as well as thyroid were computed using Monte Carlo modeling with an anatomically-appropriate model of trout thyroid structure. Activity concentration data was used in conjunction with the calculated DCFs to estimate dose rates and ultimately determine cumulative radiation dose (Gy) to the thyroids after 32 days. The estimated cumulative thyroid doses at 32 days post-release ranged from 6 mGy to 18 mGy per 1 Bq mL-1 of initial 131I in the water, depending upon fish size. The subsequent studies in Part 1 seek to develop and compare different, increasingly detailed anatomical phantoms for O. mykiss for the purpose of estimating organ radiation dose and dose rates from 131I uptake and from molybdenum-99 (99Mo) uptake. Model comparison and refinement is important to the process of determining both dose rates and dose effects, and we develop and compare three models for O. mykiss: a simplistic geometry considering a single organ, a more specific geometry employing anatomically relevant organ size and location, and voxel reconstruction of internal anatomy obtained from CT imaging (referred to as CSUTROUT). Dose Conversion

  1. Nonlinear Dynamics In Quantum Physics -- Quantum Chaos and Quantum Instantons

    OpenAIRE

    Kröger, H.

    2003-01-01

    We discuss the recently proposed quantum action - its interpretation, its motivation, its mathematical properties and its use in physics: quantum mechanical tunneling, quantum instantons and quantum chaos.

  2. Direct quantitative screening of influenza A virus without DNA amplification by single-particle dual-mode total internal reflection scattering.

    Science.gov (United States)

    Lee, Seungah; Chakkarapani, Suresh Kumar; Yeung, Edward S; Kang, Seong Ho

    2017-01-15

    Quantitative screening of influenza A (H7N9) virus without DNA amplification was performed based on single-particle dual-mode total internal reflection scattering (SD-TIRS) with a transmission grating (TG). A gold nanopad was utilized as a substrate for the hybridization of probe DNA molecules with the TIRS nanotag (silver-nanoparticle). The TG effectively isolated the scattering signals in first-order spectral images (n=+1) of the nanotag from that of the substrate, providing excellent enhancement of signal-to-noise and selectivity. By using single-DNA molecule/TIRS nanotag hybridization, target DNA molecules of H7N9 were detected down to 74 zM, which is at least 100,000 times lower than the current detection limit of 9.4fM. By simply modifying the design of the probe DNA molecules, this technique can be used to directly screen other viral DNAs in various human biological samples at the single-molecule level without target amplification. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Bicovariant quantum algebras and quantum Lie algebras

    International Nuclear Information System (INIS)

    Schupp, P.; Watts, P.; Zumino, B.

    1993-01-01

    A bicovariant calculus of differential operators on a quantum group is constructed in a natural way, using invariant maps from Fun(G q ) to U q g, given by elements of the pure braid group. These operators - the 'reflection matrix' Y= triple bond L + SL - being a special case - generate algebras that linearly close under adjoint actions, i.e. they form generalized Lie algebras. We establish the connection between the Hopf algebra formulation of the calculus and a formulation in compact matrix form which is quite powerful for actual computations and as applications we find the quantum determinant and an orthogonality relation for Y in SO q (N). (orig.)

  4. Quantum-well enhancement of the Goos-Hänchen shift for p-polarized beams in a two prism configuration

    DEFF Research Database (Denmark)

    Broe, Jacob; Keller, Ole

    2002-01-01

    It is predicted that the Goos-Hänchen effect can be resonantly enhanced by placing a metallic quantum well (ultrathin film) at the dielectric-vacuum (air) interface. We study the enhancement of the phenomenon, as it appears in frustrated total internal reflection with p-polarized light, both...... by depositing quantum wells on the glass-vacuum interfaces to obtain a better spatial photon localization....

  5. Quantum interaction. Selected papers

    Energy Technology Data Exchange (ETDEWEB)

    Atmanspacher, Harald [Eidgenoessische Technische Hochschule, Zurich (Switzerland); Haven, Emmanuel [Leicester Univ. (United Kingdom). School of Management; Kitto, Kirsty [Queensland Univ. of Technology, Brisbane, QLD (Australia); Raine, Derek (ed.) [Leicester Univ. (United Kingdom). Centre for Interdisciplinary Science

    2014-07-01

    This book constitutes the refereed proceedings of the 7th International Conference on Quantum Interaction, QI 2013, held in Leicester, UK, in July 2013. The 31 papers presented in this book were carefully selected from numerous submissions. The papers cover various topics on quantum interaction and revolve around four themes: information processing/retrieval/semantic representation and logic; cognition and decision making; finance/economics and social structures and biological systems.

  6. Quantum interaction. Proceedings

    International Nuclear Information System (INIS)

    Bruza, Peter; Rijsbergen, Keith van

    2009-01-01

    This book constitutes the refereed proceedings of the Third International Symposium on Quantum Interaction, QI 2009, held in Saarbruecken, Germany, in March 2009. The 21 revised full papers presented together with the 3 position papers were carefully reviewed and selected from numerous submissions. The papers show the cross-disciplinary nature of quantum interaction covering topics such as computation, cognition, decision theory, information retrieval, information systems, social interaction, computational linguistics and finance. (orig.)

  7. Quantum interaction. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Bruza, Peter [Queensland Univ. of Technology, Brisbane (Australia). Faculty of Science and Technology; Sofge, Donald [Navy Center for Applied Research in Artificial Intelligence, Washington, DC (United States). Naval Research Lab.; Lawless, William [Paine Coll., Augusta, GA (United States); Rijsbergen, Keith van [Glasgow Univ. (United Kingdom). Dept. of Computing Science; Klusch, Matthias (eds.) [German Research Center for Artificial Intelligence, Saarbruecken (Germany)

    2009-07-01

    This book constitutes the refereed proceedings of the Third International Symposium on Quantum Interaction, QI 2009, held in Saarbruecken, Germany, in March 2009. The 21 revised full papers presented together with the 3 position papers were carefully reviewed and selected from numerous submissions. The papers show the cross-disciplinary nature of quantum interaction covering topics such as computation, cognition, decision theory, information retrieval, information systems, social interaction, computational linguistics and finance. (orig.)

  8. Quantum mechanics

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    The book is on quantum mechanics. The emphasis is on the basic concepts and the methodology. The chapters include: Breakdown of classical concepts; Quantum mechanical concepts; Basic postulates of quantum mechanics; solution of problems in quantum mechanics; Simple harmonic oscillator; and Angular Momentum

  9. Quantum fluctuations

    International Nuclear Information System (INIS)

    Reynaud, S.; Giacobino, S.; Zinn-Justin, J.

    1997-01-01

    This course is dedicated to present in a pedagogical manner the recent developments in peculiar fields concerned by quantum fluctuations: quantum noise in optics, light propagation through dielectric media, sub-Poissonian light generated by lasers and masers, quantum non-demolition measurements, quantum electrodynamics applied to cavities and electrical circuits involving superconducting tunnel junctions. (A.C.)

  10. The Reflective Learning Continuum: Reflecting on Reflection

    Science.gov (United States)

    Peltier, James W.; Hay, Amanda; Drago, William

    2005-01-01

    The importance of reflection to marketing educators is increasingly recognized. However, there is a lack of empirical research that considers reflection within the context of both the marketing and general business education literature. This article describes the use of an instrument that can be used to measure four identified levels of a…

  11. Quantum radar

    CERN Document Server

    Lanzagorta, Marco

    2011-01-01

    This book offers a concise review of quantum radar theory. Our approach is pedagogical, making emphasis on the physics behind the operation of a hypothetical quantum radar. We concentrate our discussion on the two major models proposed to date: interferometric quantum radar and quantum illumination. In addition, this book offers some new results, including an analytical study of quantum interferometry in the X-band radar region with a variety of atmospheric conditions, a derivation of a quantum radar equation, and a discussion of quantum radar jamming.This book assumes the reader is familiar w

  12. Autocompensating quantum cryptography

    International Nuclear Information System (INIS)

    Bethune, Donald S.; Risk, William P.

    2002-01-01

    Quantum cryptographic key distribution (QKD) uses extremely faint light pulses to carry quantum information between two parties (Alice and Bob), allowing them to generate a shared, secret cryptographic key. Autocompensating QKD systems automatically and passively compensate for uncontrolled time-dependent variations of the optical fibre properties by coding the information as a differential phase between orthogonally polarized components of a light pulse sent on a round trip through the fibre, reflected at mid-course using a Faraday mirror. We have built a prototype system based on standard telecom technology that achieves a privacy-amplified bit generation rate of ∼1000 bits s -1 over a 10 km optical fibre link. Quantum cryptography is an example of an application that, by using quantum states of individual particles to represent information, accomplishes a practical task that is impossible using classical means. (author)

  13. Impact of internal electric field and localization effect on quantum well excitons in AlGaN/GaN/InGaN light emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    Chichibu, S.F. [Tsukuba Univ., Ibaraki (Japan). Inst. of Applied Physics; Sota, T. [Waseda Univ., Tokyo (Japan). Dept. of Electrical, Electronics, and Computer Engineering; Wada, K. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Materials Science and Engineering; Brandt, O.; Ploog, K.H. [Paul-Drude-Inst. fuer Festkoerperelektronik, Berlin (Germany); DenBaars, S.P. [Dept. of Materials Engineering, Univ. of California, Santa Barbara, CA (United States); Nakamura, S. [Dept. of Research and Development, Nichia Chemical Industries Ltd., Tokushima (Japan)

    2001-01-01

    Strained In{sub x}Ga{sub 1-x}N quantum wells (QWs) on thick GaN base layers were investigated to verify the importance of localized QW excitons in their spontaneous emission mechanisms. A strength of the internal piezoelectric field (F{sub PZ}) across the QW increases with increasing x up to 1.4 MV/cm for x = 0.25, since the in-plain strain increases. For the QWs with the well thickness L greater than spectra of both hexagonal and cubic InGaN QWs exhibited a broad band-tail regardless of the presence of F{sub PZ} normal to the QW plane. The luminescence peak energy of the 3 nm thick QWs was higher than the bandgap energy of the unstrained bulk crystal for x < 0.15, showing that doping of Si in barriers or injection of carriers effectively screens the field. The emission lifetime increased with increasing monitoring wavelength. Also, a temperature-induced change in the luminescence peak energy decreased with increasing x. The real-space variation of the luminescence peak energy was confirmed by the spatially-resolved monochromatic cathodoluminescence mapping method. The localization depth increases with increasing x. The carrier localization is confirmed to originate from the effective bandgap inhomogeneity due to a fluctuation of the local InN mole fraction, which is enhanced by the large and composition-dependent bowing parameter of InGaN material. (orig.)

  14. Synthesis, characterization and applications of carboxylated and polyethylene-glycolated bifunctionalized InP/ZnS quantum dots in cellular internalization mediated by cell-penetrating peptides.

    Science.gov (United States)

    Liu, Betty R; Winiarz, Jeffrey G; Moon, Jong-Sik; Lo, Shih-Yen; Huang, Yue-Wern; Aronstam, Robert S; Lee, Han-Jung

    2013-11-01

    Semiconductor nanoparticles, also known as quantum dots (QDs), are widely used in biomedical imaging studies and pharmaceutical research. Cell-penetrating peptides (CPPs) are a group of small peptides that are able to traverse cell membrane and deliver a variety of cargoes into living cells. CPPs deliver QDs into cells with minimal nonspecific absorption and toxic effect. In this study, water-soluble, monodisperse, carboxyl-functionalized indium phosphide (InP)/zinc sulfide (ZnS) QDs coated with polyethylene glycol lipids (designated QInP) were synthesized for the first time. The physicochemical properties (optical absorption, fluorescence and charging state) and cellular internalization of QInP and CPP/QInP complexes were characterized. CPPs noncovalently interact with QInP in vitro to form stable CPP/QInP complexes, which can then efficiently deliver QInP into human A549 cells. The introduction of 500nM of CPP/QInP complexes and QInP at concentrations of less than 1μM did not reduce cell viability. These results indicate that carboxylated and polyethylene-glycolylated (PEGylated) bifunctionalized QInP are biocompatible nanoparticles with potential for use in biomedical imaging studies and drug delivery applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Quantum ontologies

    International Nuclear Information System (INIS)

    Stapp, H.P.

    1988-12-01

    Quantum ontologies are conceptions of the constitution of the universe that are compatible with quantum theory. The ontological orientation is contrasted to the pragmatic orientation of science, and reasons are given for considering quantum ontologies both within science, and in broader contexts. The principal quantum ontologies are described and evaluated. Invited paper at conference: Bell's Theorem, Quantum Theory, and Conceptions of the Universe, George Mason University, October 20-21, 1988. 16 refs

  16. Differential calculus on quantum spaces and quantum groups

    International Nuclear Information System (INIS)

    Zumino, B.

    1992-01-01

    A review of recent developments in the quantum differential calculus. The quantum group GL q (n) is treated by considering it as a particular quantum space. Functions on SL q (n) are defined as a subclass of functions on GL q (n). The case of SO q (n) is also briefly considered. These notes cover part of a lecture given at the XIX International Conference on Group Theoretic Methods in Physics, Salamanca, Spain 1992

  17. International

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    This rubric reports on 10 short notes about international economical facts about nuclear power: Electricite de France (EdF) and its assistance and management contracts with Eastern Europe countries (Poland, Hungary, Bulgaria); Transnuclear Inc. company (a 100% Cogema daughter company) acquired the US Vectra Technologies company; the construction of the Khumo nuclear power plant in Northern Korea plays in favour of the reconciliation between Northern and Southern Korea; the delivery of two VVER 1000 Russian reactors to China; the enforcement of the cooperation agreement between Euratom and Argentina; Japan requested for the financing of a Russian fast breeder reactor; Russia has planned to sell a floating barge-type nuclear power plant to Indonesia; the control of the Swedish reactor vessels of Sydkraft AB company committed to Tractebel (Belgium); the renewal of the nuclear cooperation agreement between Swiss and USA; the call for bids from the Turkish TEAS electric power company for the building of the Akkuyu nuclear power plant answered by three candidates: Atomic Energy of Canada Limited (AECL), Westinghouse (US) and the French-German NPI company. (J.S.)

  18. What we do and do not know about women and kidney diseases; Questions unanswered and answers unquestioned: Reflection on World Kidney Day and International Woman’s Day

    Directory of Open Access Journals (Sweden)

    Giorgina B Piccoli

    2018-03-01

    Full Text Available Chronic Kidney Disease affects approximately 10% of the world’s adult population: it is within the top 20 causes of death worldwide, and its impact on patients and their families can be devastating. World Kidney Day and International Women’s Day in 2018 coincide, thus offering an opportunity to reflect on the importance of women’s health and specifically their kidney health, on the community, and the next generations, as well as to strive to be more curious about the unique aspects of kidney disease in women so that we may apply those learnings more broadly. Girls and women, who make up approximately 50% of the world’s population, are important contributors to society and their families. Gender differences continue to exist around the world in access to education, medical care, and participation in clinical studies. Pregnancy is a unique state for women, offering an opportunity for diagnosis of kidney disease, but also a state where acute and chronic kidney diseases may manifest, and which may impact future generations with respect to kidney health. There are various autoimmune and other conditions that are more likely to impact women with profound consequences for child bearing, and on the fetus. Women have different complications on dialysis than men, and are more likely to be donors than recipients of kidney transplants. In this editorial, we focus on what we do and do not know about women, kidney health, and kidney disease, and what we might learn in the future to improve outcomes worldwide

  19. What we do and do not know about women and kidney diseases; questions unanswered and answers unquestioned: Reflection on World Kidney Day and International Woman's Day

    Directory of Open Access Journals (Sweden)

    Giorgina B. Piccoli

    2018-03-01

    Full Text Available Chronic kidney disease affects approximately 10% of the world's adult population: it is within the top 20 causes of death worldwide, and its impact on patients and their families can be devastating. World Kidney Day and International Women's Day in 2018 coincide, thus offering an opportunity to reflect on the importance of women's health and specifically their kidney health, on the community, and the next generations, as well as to strive to be more curious about the unique aspects of kidney disease in women so that we may apply those learnings more broadly.Girls and women, who make up approximately 50% of the world's population, are important contributors to society and their families. Gender differences continue to exist around the world in access to education, medical care, and participation in clinical studies. Pregnancy is a unique state for women, offering an opportunity for diagnosis of kidney disease, but also a state where acute and chronic kidney diseases may manifest, and which may impact future generations with respect to kidney health. There are various autoimmune and other conditions that are more likely to impact women with profound consequences for child bearing, and on the fetus. Women have different complications on dialysis than men, and are more likely to be donors than recipients of kidney transplants.In this editorial, we focus on what we do and do not know about women, kidney health, and kidney disease, and what we might learn in the future to improve outcomes worldwide. Keywords: Women, Access to care, Kidney health, Acute and chronic kidney disease, Inequities

  20. A Q-Methodology approach to investigating the relationship between level of reflection and typologies among prospective teachers in the physics learning assistant program at Florida International University

    Science.gov (United States)

    Cochran, Geraldine L.

    The purpose of this mixed methods study was to understand physics Learning Assistants' (LAs) views on reflective teaching, expertise in teaching, and LA program teaching experience and to determine if views predicted level of reflection evident in writing. Interviews were conducted in Phase One, Q methodology was used in Phase Two, and level of reflection in participants' writing was assessed using a rubric based on Hatton and Smith's (1995) "Criteria for the Recognition of Evidence for Different Types of Reflective Writing" in Phase Three. Interview analysis revealed varying perspectives on content knowledge, pedagogical knowledge, and experience in relation to expertise in teaching. Participants revealed that they engaged in reflection on their teaching, believed reflection helps teachers improve, and found peer reflection beneficial. Participants believed teaching experience in the LA program provided preparation for teaching, but that more preparation was needed to teach. Three typologies emerged in Phase Two. Type One LAs found participation in the LA program rewarding and believed expertise in teaching does not require expertise in content or pedagogy, but it develops over time from reflection. Type Two LAs valued reflection, but not writing reflections, felt the LA program teaching experience helped them decide on non-teaching careers and helped them confront gaps in their physics knowledge. Type Three LAs valued reflection, believed expertise in content and pedagogy are necessary for expert teaching, and felt LA program teaching experience increased their likelihood of becoming teachers, but did not prepare them for teaching. Writing assignments submitted in Phase Three were categorized as 19% descriptive writing, 60% descriptive reflections, and 21% dialogic reflections. No assignments were categorized as critical reflection. Using ordinal logistic regression, typologies that emerged in Phase Two were not found to be predictors for the level of reflection

  1. The second quantum revolution

    International Nuclear Information System (INIS)

    Larousserie, D.

    2008-01-01

    The development of quantum mechanics has now reached such a level that we can consider its promising applications in various fields as a looming second quantum revolution. The classical computer that relies on logical gates is out, now quantum properties open the way to new machines that will simulate nature's events exactly, this will be possible because both nature and the machine will be quantum. The machine will mimic nature and some problems like high temperature superconductivity that resist any modelling will be reproduced easily and then put within hand reach to be understood. Another application is quantum imaging based on the property of quantum entanglement. In the case of 2 entangled particle beams, the measurement of the properties of one beam fixes the values on the other beam. In other words, in case of entangled fluctuations, the measurement of the fluctuations on one beam fixes the value of the fluctuations on the other beam and by subtracting them on the second beam, we get a more accurate result: we have made the background noise disappear. Another application, that has already entered our daily life, is the generation of random numbers in a simple way: quantum mechanics states that a photon has a probability of 50 % to be reflected by a semi-reflecting plate and be detected, this experimental setting is a perfect toss play. The most known application of quantum mechanics is cryptography to assure the security of information transfer. Various systems have proved its efficiency but this technology is hampered by the damping of the signal in optical fibers and is reliable on distances shorter than a few hundreds kilometers. (A.C.)

  2. Quantum Computer Games: Quantum Minesweeper

    Science.gov (United States)

    Gordon, Michal; Gordon, Goren

    2010-01-01

    The computer game of quantum minesweeper is introduced as a quantum extension of the well-known classical minesweeper. Its main objective is to teach the unique concepts of quantum mechanics in a fun way. Quantum minesweeper demonstrates the effects of superposition, entanglement and their non-local characteristics. While in the classical…

  3. Calculation of the tunneling time using the extended probability of the quantum histories approach

    International Nuclear Information System (INIS)

    Rewrujirek, Jiravatt; Hutem, Artit; Boonchui, Sutee

    2014-01-01

    The dwell time of quantum tunneling has been derived by Steinberg (1995) [7] as a function of the relation between transmission and reflection times τ t and τ r , weighted by the transmissivity and the reflectivity. In this paper, we reexamine the dwell time using the extended probability approach. The dwell time is calculated as the weighted average of three mutually exclusive events. We consider also the scattering process due to a resonance potential in the long-time limit. The results show that the dwell time can be expressed as the weighted sum of transmission, reflection and internal probabilities.

  4. Quantum memristors

    Science.gov (United States)

    Pfeiffer, P.; Egusquiza, I. L.; Di Ventra, M.; Sanz, M.; Solano, E.

    2016-01-01

    Technology based on memristors, resistors with memory whose resistance depends on the history of the crossing charges, has lately enhanced the classical paradigm of computation with neuromorphic architectures. However, in contrast to the known quantized models of passive circuit elements, such as inductors, capacitors or resistors, the design and realization of a quantum memristor is still missing. Here, we introduce the concept of a quantum memristor as a quantum dissipative device, whose decoherence mechanism is controlled by a continuous-measurement feedback scheme, which accounts for the memory. Indeed, we provide numerical simulations showing that memory effects actually persist in the quantum regime. Our quantization method, specifically designed for superconducting circuits, may be extended to other quantum platforms, allowing for memristor-type constructions in different quantum technologies. The proposed quantum memristor is then a building block for neuromorphic quantum computation and quantum simulations of non-Markovian systems. PMID:27381511

  5. Reflective photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Lentine, Anthony L.; Nielson, Gregory N.; Cruz-Campa, Jose Luis; Okandan, Murat; Goeke, Ronald S.

    2018-03-06

    A photovoltaic module includes colorized reflective photovoltaic cells that act as pixels. The colorized reflective photovoltaic cells are arranged so that reflections from the photovoltaic cells or pixels visually combine into an image on the photovoltaic module. The colorized photovoltaic cell or pixel is composed of a set of 100 to 256 base color sub-pixel reflective segments or sub-pixels. The color of each pixel is determined by the combination of base color sub-pixels forming the pixel. As a result, each pixel can have a wide variety of colors using a set of base colors, which are created, from sub-pixel reflective segments having standard film thicknesses.

  6. BRICS and Quantum Information Processing

    DEFF Research Database (Denmark)

    Schmidt, Erik Meineche

    1998-01-01

    BRICS is a research centre and international PhD school in theoretical computer science, based at the University of Aarhus, Denmark. The centre has recently become engaged in quantum information processing in cooperation with the Department of Physics, also University of Aarhus. This extended...... abstract surveys activities at BRICS with special emphasis on the activities in quantum information processing....

  7. Guests and Hosts--The Global Market in International Higher Education: Reflections on the Japan-UK Axis in Study Abroad

    Science.gov (United States)

    Walker, Patricia

    2010-01-01

    Taking as a starting point the present ubiquity of international student mobility, contrasting paradigms of international study are offered through a critical examination of two nations. The UK is presented as a leading host nation and provider of international higher education, significant revenue from which is central to the prosperity of the…

  8. Quantum Dots and Andreev Reflections in Graphene

    NARCIS (Netherlands)

    Liu, X.L.

    2010-01-01

    Graphene is an exceptionally thin semiconductor that consists of only one atomic layer of carbon atoms. The electrons in graphene live in a strictly two-dimensional (2D) world. In addition to this remarkable 2Dness, it is also peculiar that the behavior of the electrons in graphene is governed by

  9. “Intellectual developmental disorders”: reflections on the international consensus document for redefining “mental retardation-intellectual disability” in ICD-11

    Science.gov (United States)

    Bertelli, Marco O.; Munir, Kerim; Harris, James; Salvador-Carulla, Luis

    2016-01-01

    Purpose The debate as to whether intellectual disability (ID) should be conceptualized as a health condition or as a disability has intensified as the revision of World Health Organization’s (WHO’s) International Classification of Diseases (ICD) is being finalized. Defining ID as a health condition is central to retaining it in ICD, with significant implications for health policy and access to health services. The purpose of this paper is to include some reflections on the consensus document produced by the first WHO Working Group on the Classification of MR (WHO WG-MR) and on the process that was followed to realize it. The consensus report was the basis for the development of official recommendations sent to the WHO Advisory Group for ICD-11. Design/methodology/approach A mixed qualitative approach was followed in a series of meetings leading to the final consensus report submitted to the WHO Advisory group. These recommendations combined prior expert knowledge with available evidence; a nominal approach was followed throughout with face-to-face conferences. Findings The WG recommended a synonym set (“synset”) ontological approach to the conceptualisation of this health condition underlying a clinical rationale for its diagnosis. It proposed replacing MR with Intellectual Developmental Disorders (IDD) in ICD-11, defined as “a group of developmental conditions characterized by a significant impairment of cognitive functions, which are associated with limitations of learning, adaptive behaviour and skills”. The WG further advised that IDD be included under the parent category of neurodevelopmental disorders, that current distinctions (mild, moderate, severe and profound) be continued as severity qualifiers, and that problem behaviours removed from its core classification structure and instead described as associated features. Originality/value Within the ID/IDD synset two different names combine distinct aspects under a single construct that describes

  10. Principles and applications of quantum control engineering.

    Science.gov (United States)

    Gough, John E

    2012-11-28

    This is a brief survey of quantum feedback control and specifically follows on from the two-day conference Principles and applications of quantum control engineering, which took place in the Kavli Royal Society International Centre at Chicheley Hall, on 12-13 December 2011. This was the eighth in a series of principles and applications of control to quantum systems workshops.

  11. Quantum computers and quantum computations

    International Nuclear Information System (INIS)

    Valiev, Kamil' A

    2005-01-01

    This review outlines the principles of operation of quantum computers and their elements. The theory of ideal computers that do not interact with the environment and are immune to quantum decohering processes is presented. Decohering processes in quantum computers are investigated. The review considers methods for correcting quantum computing errors arising from the decoherence of the state of the quantum computer, as well as possible methods for the suppression of the decohering processes. A brief enumeration of proposed quantum computer realizations concludes the review. (reviews of topical problems)

  12. Quantum robots and quantum computers

    Energy Technology Data Exchange (ETDEWEB)

    Benioff, P.

    1998-07-01

    Validation of a presumably universal theory, such as quantum mechanics, requires a quantum mechanical description of systems that carry out theoretical calculations and systems that carry out experiments. The description of quantum computers is under active development. No description of systems to carry out experiments has been given. A small step in this direction is taken here by giving a description of quantum robots as mobile systems with on board quantum computers that interact with different environments. Some properties of these systems are discussed. A specific model based on the literature descriptions of quantum Turing machines is presented.

  13. Quantum Phase Extraction in Isospectral Electronic Nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Christopher

    2010-04-28

    Quantum phase is not a direct observable and is usually determined by interferometric methods. We present a method to map complete electron wave functions, including internal quantum phase information, from measured single-state probability densities. We harness the mathematical discovery of drum-like manifolds bearing different shapes but identical resonances, and construct quantum isospectral nanostructures possessing matching electronic structure but divergent physical structure. Quantum measurement (scanning tunneling microscopy) of these 'quantum drums' [degenerate two-dimensional electron states on the Cu(111) surface confined by individually positioned CO molecules] reveals that isospectrality provides an extra topological degree of freedom enabling robust quantum state transplantation and phase extraction.

  14. Quantum electrodynamics of strong fields

    International Nuclear Information System (INIS)

    Greiner, W.

    1983-01-01

    Quantum Electrodynamics of Strong Fields provides a broad survey of the theoretical and experimental work accomplished, presenting papers by a group of international researchers who have made significant contributions to this developing area. Exploring the quantum theory of strong fields, the volume focuses on the phase transition to a charged vacuum in strong electric fields. The contributors also discuss such related topics as QED at short distances, precision tests of QED, nonperturbative QCD and confinement, pion condensation, and strong gravitational fields In addition, the volume features a historical paper on the roots of quantum field theory in the history of quantum physics by noted researcher Friedrich Hund

  15. Quantum Cosmology

    OpenAIRE

    Kiefer, Claus; Sandhoefer, Barbara

    2008-01-01

    We give an introduction into quantum cosmology with emphasis on its conceptual parts. After a general motivation we review the formalism of canonical quantum gravity on which discussions of quantum cosmology are usually based. We then present the minisuperspace Wheeler--DeWitt equation and elaborate on the problem of time, the imposition of boundary conditions, the semiclassical approximation, the origin of irreversibility, and singularity avoidance. Restriction is made to quantum geometrodyn...

  16. Quantum criticality.

    Science.gov (United States)

    Coleman, Piers; Schofield, Andrew J

    2005-01-20

    As we mark the centenary of Albert Einstein's seminal contribution to both quantum mechanics and special relativity, we approach another anniversary--that of Einstein's foundation of the quantum theory of solids. But 100 years on, the same experimental measurement that puzzled Einstein and his contemporaries is forcing us to question our understanding of how quantum matter transforms at ultra-low temperatures.

  17. Quantum Computing

    Indian Academy of Sciences (India)

    It was suggested that the dynamics of quantum systems could be used to perform computation in a much more efficient way. After this initial excitement, things slowed down for some time till 1994 when Peter Shor announced his polynomial time factorization algorithm 1 which uses quantum dynamics. The study of quantum ...

  18. Quantum Computing

    Indian Academy of Sciences (India)

    quantum dynamics. The study of quantum systems for computation has come into its own since then. In this article we will look at a few concepts which make this framewor k so powerful. 2. Quantum Physics Basics. Consider an electron (say, in a H atom) with two energy levels (ground state and one excited state). In general ...

  19. Quantum Computing

    Indian Academy of Sciences (India)

    In the first part of this article, we had looked at how quantum physics can be harnessed to make the building blocks of a quantum computer. In this concluding part, we look at algorithms which can exploit the power of this computational device, and some practical difficulties in building such a device. Quantum Algorithms.

  20. Reflection: A Socratic approach.

    Science.gov (United States)

    Van Seggelen-Damen, Inge C M; Van Hezewijk, René; Helsdingen, Anne S; Wopereis, Iwan G J H

    2017-12-01

    Reflection is a fuzzy concept. In this article we reveal the paradoxes involved in studying the nature of reflection. Whereas some scholars emphasize its discursive nature, we go further and underline its resemblance to the self-biased dialogue Socrates had with the slave in Plato's Meno . The individual and internal nature of the reflection process creates difficulty for studying it validly and reliably. We focus on methodological issues and use Hans Linschoten's view of coupled systems to identify, analyze, and interpret empirical research on reflection. We argue that researchers and research participants can take on roles in several possible system couplings. Depending on who controls the manipulation of the stimulus, who controls the measuring instrument, who interprets the measurement and the response, different types of research questions can be answered. We conclude that reflection may be validly studied by combining different couplings of experimenter, manipulation, stimulus, participant, measurement, and response.

  1. Quantum dynamics of quantum bits

    International Nuclear Information System (INIS)

    Nguyen, Bich Ha

    2011-01-01

    The theory of coherent oscillations of the matrix elements of the density matrix of the two-state system as a quantum bit is presented. Different calculation methods are elaborated in the case of a free quantum bit. Then the most appropriate methods are applied to the study of the density matrices of the quantum bits interacting with a classical pumping radiation field as well as with the quantum electromagnetic field in a single-mode microcavity. The theory of decoherence of a quantum bit in Markovian approximation is presented. The decoherence of a quantum bit interacting with monoenergetic photons in a microcavity is also discussed. The content of the present work can be considered as an introduction to the study of the quantum dynamics of quantum bits. (review)

  2. Personal Reflections

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education. Personal Reflections. Articles in Resonance – Journal of Science Education. Volume 6 Issue 3 March 2001 pp 90-93 Personal Reflections. Why did I opt for Career in Science? Jayant V Narlikar · More Details Fulltext PDF. Volume 9 Issue 8 August 2004 pp 89-89 ...

  3. Reflection groups

    International Nuclear Information System (INIS)

    Eggermont, G.

    2006-01-01

    In 2005, PISA organised proactive meetings of reflection groups on involvement in decision making, expert culture and ethical aspects of radiation protection.All reflection group meetings address particular targeted audiences while the output publication in book form is put forward

  4. Corrugated Quantum Well Infrared Photodetector Focal Plane Array Test Results

    Science.gov (United States)

    Goldberg, A.; Choi, K. K.; Das, N. C.; La, A.; Jhabvala, M.

    1999-01-01

    The corrugated quantum-well infrared photodetector (C-QWIP) uses total internal reflection to couple normal incident light into the optically active quantum wells. The coupling efficiency has been shown to be relatively independent of the pixel size and wavelength thus making the C-QWIP a candidate for detectors over the entire infrared spectrum. The broadband coupling efficiency of the C-QWIP makes it an ideal candidate for multiwavelength detectors. We fabricated and tested C-QWIP focal plane arrays (FPAs) with cutoff wavelengths of 11.2 and 16.2 micrometers. Each FPA has 256 x 256 pixels that are bump-bonded to a direct injection readout circuit. Both FPAs provided infrared imagery with good aesthetic attributes. For the 11.2-micrometers FPA, background-limited performance (BLIP) was observed at 60 K with f/3 optics. For the 16.2-micrometers FPA, BLIP was observed at 38 K. Besides the reduction of dark current in C-QWIP structures, the measured internal quantum efficiency (eta) remains to be high. The values for responsivity and quantum efficiency obtained from the FPA results agree well with those measured for single devices.

  5. Quantifying Reflection

    DEFF Research Database (Denmark)

    Alcock, Gordon Lindsay

    2013-01-01

    This paper documents 1st semester student reflections on “learning to learn” in a team-based PBL environment with quantitative and qualitative student reflective feedback on the learning gains of 60 Architectural Technology and Construction Management students at VIA University College, Denmark....... It contrasts the students’ self-assessment in a range of ‘product’ skills such as Revit, Structural Design, Mathematics of construction, Technical Installations; as well as ‘process’ competencies such as ‘Working in a team’, Sharing knowledge, Maintaining a portfolio and Reflecting ON learning and FOR learning......´ These are all based on Blooms taxonomy and levels of competence and form a major part of individual student and group learning portfolios. Key Words :Project-Based learning, Reflective Portfolios, Self assessment, Defining learning gains, Developing learning strategies , Reflections on and for learning...

  6. Quantum cheques

    Science.gov (United States)

    Moulick, Subhayan Roy; Panigrahi, Prasanta K.

    2016-06-01

    We propose the idea of a quantum cheque scheme, a cryptographic protocol in which any legitimate client of a trusted bank can issue a cheque, that cannot be counterfeited or altered in anyway, and can be verified by a bank or any of its branches. We formally define a quantum cheque and present the first unconditionally secure quantum cheque scheme and show it to be secure against any no-signalling adversary. The proposed quantum cheque scheme can been perceived as the quantum analog of Electronic Data Interchange, as an alternate for current e-Payment Gateways.

  7. Quantum walk with one variable absorbing boundary

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Feiran [Key Laboratory of Quantum Information and Quantum Optoelectronic Devices, Shaanxi Province, Xi' an Jiaotong University, Xi' an 710049 (China); Department of Applied Physics, School of Science, Xi' an Jiaotong University, Xi' an 710049 (China); Zhang, Pei, E-mail: zhangpei@mail.ustc.edu.cn [Key Laboratory of Quantum Information and Quantum Optoelectronic Devices, Shaanxi Province, Xi' an Jiaotong University, Xi' an 710049 (China); Department of Applied Physics, School of Science, Xi' an Jiaotong University, Xi' an 710049 (China); Wang, Yunlong; Liu, Ruifeng; Gao, Hong; Li, Fuli [Key Laboratory of Quantum Information and Quantum Optoelectronic Devices, Shaanxi Province, Xi' an Jiaotong University, Xi' an 710049 (China); Department of Applied Physics, School of Science, Xi' an Jiaotong University, Xi' an 710049 (China)

    2017-01-15

    Quantum walks constitute a promising ingredient in the research on quantum algorithms; consequently, exploring different types of quantum walks is of great significance for quantum information and quantum computation. In this study, we investigate the progress of quantum walks with a variable absorbing boundary and provide an analytical solution for the escape probability (the probability of a walker that is not absorbed by the boundary). We simulate the behavior of escape probability under different conditions, including the reflection coefficient, boundary location, and initial state. Moreover, it is also meaningful to extend our research to the situation of continuous-time and high-dimensional quantum walks. - Highlights: • A novel scheme about quantum walk with variable boundary is proposed. • The analytical results of the survival probability from the absorbing boundary. • The behavior of survival probability under different boundary conditions. • The influence of different initial coin states on the survival probability.

  8. Quantum dots

    International Nuclear Information System (INIS)

    Kouwenhoven, L.; Marcus, C.

    1998-01-01

    Quantum dots are man-made ''droplets'' of charge that can contain anything from a single electron to a collection of several thousand. Their typical dimensions range from nanometres to a few microns, and their size, shape and interactions can be precisely controlled through the use of advanced nanofabrication technology. The physics of quantum dots shows many parallels with the behaviour of naturally occurring quantum systems in atomic and nuclear physics. Indeed, quantum dots exemplify an important trend in condensed-matter physics in which researchers study man-made objects rather than real atoms or nuclei. As in an atom, the energy levels in a quantum dot become quantized due to the confinement of electrons. With quantum dots, however, an experimentalist can scan through the entire periodic table by simply changing a voltage. In this article the authors describe how quantum dots make it possible to explore new physics in regimes that cannot otherwise be accessed in the laboratory. (UK)

  9. Quantum random number generator

    Science.gov (United States)

    Soubusta, Jan; Haderka, Ondrej; Hendrych, Martin

    2001-03-01

    Since reflection or transmission of a quantum particle on a beamsplitter is inherently random quantum process, a device built on this principle does not suffer from drawbacks of neither pseudo-random computer generators or classical noise sources. Nevertheless, a number of physical conditions necessary for high quality random numbers generation must be satisfied. Luckily, in quantum optics realization they can be well controlled. We present an easy random number generator based on the division of weak light pulses on a beamsplitter. The randomness of the generated bit stream is supported by passing the data through series of 15 statistical test. The device generates at a rate of 109.7 kbit/s.

  10. Reflection ciphers

    DEFF Research Database (Denmark)

    Boura, Christina; Canteaut, Anne; Knudsen, Lars Ramkilde

    2017-01-01

    study the necessary properties for this coupling permutation. Special care has to be taken of some related-key distinguishers since, in the context of reflection ciphers, they may provide attacks in the single-key setting.We then derive some criteria for constructing secure reflection ciphers...... and analyze the security properties of different families of coupling permutations. Finally, we concentrate on the case of reflection block ciphers and, as an illustration, we provide concrete examples of key schedules corresponding to several coupling permutations, which lead to new variants of the block...

  11. Wave Reflection Model Tests

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Larsen, Brian Juul

    The investigation concerns the design of a new internal breakwater in the main port of Ibiza. The objective of the model tests was in the first hand to optimize the cross section to make the wave reflection low enough to ensure that unacceptable wave agitation will not occur in the port. Secondly...

  12. Formalization of Quantum Protocols using Coq

    Directory of Open Access Journals (Sweden)

    Jaap Boender

    2015-11-01

    Full Text Available Quantum Information Processing, which is an exciting area of research at the intersection of physics and computer science, has great potential for influencing the future development of information processing systems. The building of practical, general purpose Quantum Computers may be some years into the future. However, Quantum Communication and Quantum Cryptography are well developed. Commercial Quantum Key Distribution systems are easily available and several QKD networks have been built in various parts of the world. The security of the protocols used in these implementations rely on information-theoretic proofs, which may or may not reflect actual system behaviour. Moreover, testing of implementations cannot guarantee the absence of bugs and errors. This paper presents a novel framework for modelling and verifying quantum protocols and their implementations using the proof assistant Coq. We provide a Coq library for quantum bits (qubits, quantum gates, and quantum measurement. As a step towards verifying practical quantum communication and security protocols such as Quantum Key Distribution, we support multiple qubits, communication and entanglement. We illustrate these concepts by modelling the Quantum Teleportation Protocol, which communicates the state of an unknown quantum bit using only a classical channel.

  13. Reflections on the international climate change negotiations: A synthesis of a working group on carbon emission policy and regulation in Brazil

    International Nuclear Information System (INIS)

    Lucon, Oswaldo; Romeiro, Viviane; Pacca, Sergio

    2013-01-01

    This short communication presents a synthesis of a Working Group on Carbon Emission Policy and Regulation held at the University of Sao Paulo, in Brazil. The document looked at the problems with the international negotiations, the options for Brazil as it attempts to control emissions, and ways to leverage the mitigation process. Several options are currently being proposed, but these are neither clear in order to support a solid polycentric approach with adequate metrics, nor a robust international coordination and a sound scientific communication. Brazil has a central role in this process, for having successful initiatives on renewable energy and deforestation control. Its leadership can demonstrate how such policies might take shape. However, the country´s future is uncertain in terms of low carbon development. Although the country is still well positioned among BRICS to find practical solutions to the stalemate in international cooperation, several internal challenges need to be harmonized. - Highlights: • The work presents results of a recent climate change mitigation policies workshop. • It assesses Brazil's potential role in shaping future policies and negotiations. • Policies are evaluated based on domestic and international effects. • Suggests how Brazil's national effort could leverage the international processes

  14. Quantum Nonlocality and Reality

    Science.gov (United States)

    Bell, Mary; Gao, Shan

    2016-09-01

    Preface; Part I. John Stewart Bell: The Physicist: 1. John Bell: the Irish connection Andrew Whitaker; 2. Recollections of John Bell Michael Nauenberg; 3. John Bell: recollections of a great scientist and a great man Gian-Carlo Ghirardi; Part II. Bell's Theorem: 4. What did Bell really prove? Jean Bricmont; 5. The assumptions of Bell's proof Roderich Tumulka; 6. Bell on Bell's theorem: the changing face of nonlocality Harvey R. Brown and Christopher G. Timpson; 7. Experimental tests of Bell inequalities Marco Genovese; 8. Bell's theorem without inequalities: on the inception and scope of the GHZ theorem Olival Freire, Jr and Osvaldo Pessoa, Jr; 9. Strengthening Bell's theorem: removing the hidden-variable assumption Henry P. Stapp; Part III. Nonlocality: Illusions or Reality?: 10. Is any theory compatible with the quantum predictions necessarily nonlocal? Bernard d'Espagnat; 11. Local causality, probability and explanation Richard A. Healey; 12. Bell inequality and many-worlds interpretation Lev Vaidman; 13. Quantum solipsism and non-locality Travis Norsen; 14. Lessons of Bell's theorem: nonlocality, yes; action at a distance, not necessarily Wayne C. Myrvold; 15. Bell non-locality, Hardy's paradox and hyperplane dependence Gordon N. Fleming; 16. Some thoughts on quantum nonlocality and its apparent incompatibility with relativity Shan Gao; 17. A reasonable thing that just might work Daniel Rohrlich; 18. Weak values and quantum nonlocality Yakir Aharonov and Eliahu Cohen; Part IV. Nonlocal Realistic Theories: 19. Local beables and the foundations of physics Tim Maudlin; 20. John Bell's varying interpretations of quantum mechanics: memories and comments H. Dieter Zeh; 21. Some personal reflections on quantum non-locality and the contributions of John Bell Basil J. Hiley; 22. Bell on Bohm Sheldon Goldstein; 23. Interactions and inequality Philip Pearle; 24. Gravitation and the noise needed in objective reduction models Stephen L. Adler; 25. Towards an objective

  15. Advances in quantum chemistry

    CERN Document Server

    Sabin, John R

    2013-01-01

    Advances in Quantum Chemistry presents surveys of current topics in this rapidly developing field that has emerged at the cross section of the historically established areas of mathematics, physics, chemistry, and biology. It features detailed reviews written by leading international researchers. This volume focuses on the theory of heavy ion physics in medicine.Advances in Quantum Chemistry presents surveys of current topics in this rapidly developing field that has emerged at the cross section of the historically established areas of mathematics, physics, chemistry, and biology. It features

  16. Weak Measurement and Quantum Correlation

    Indian Academy of Sciences (India)

    Arun Kumar Pati

    Quantum Information. These are resources which can be used to design quantum computer, quantum information processor, quantum communication and quantum information technology. Merging of quantum mechanics and information theory —quantum information science – with important developments like quantum.

  17. Quantum gravity

    International Nuclear Information System (INIS)

    Markov, M.A.; West, P.C.

    1984-01-01

    This book discusses the state of the art of quantum gravity, quantum effects in cosmology, quantum black-hole physics, recent developments in supergravity, and quantum gauge theories. Topics considered include the problems of general relativity, pregeometry, complete cosmological theories, quantum fluctuations in cosmology and galaxy formation, a new inflationary universe scenario, grand unified phase transitions and the early Universe, the generalized second law of thermodynamics, vacuum polarization near black holes, the relativity of vacuum, black hole evaporations and their cosmological consequences, currents in supersymmetric theories, the Kaluza-Klein theories, gauge algebra and quantization, and twistor theory. This volume constitutes the proceedings of the Second Seminar on Quantum Gravity held in Moscow in 1981

  18. Quantum measurement

    CERN Document Server

    Busch, Paul; Pellonpää, Juha-Pekka; Ylinen, Kari

    2016-01-01

    This is a book about the Hilbert space formulation of quantum mechanics and its measurement theory. It contains a synopsis of what became of the Mathematical Foundations of Quantum Mechanics since von Neumann’s classic treatise with this title. Fundamental non-classical features of quantum mechanics—indeterminacy and incompatibility of observables, unavoidable measurement disturbance, entanglement, nonlocality—are explicated and analysed using the tools of operational quantum theory. The book is divided into four parts: 1. Mathematics provides a systematic exposition of the Hilbert space and operator theoretic tools and relevant measure and integration theory leading to the Naimark and Stinespring dilation theorems; 2. Elements develops the basic concepts of quantum mechanics and measurement theory with a focus on the notion of approximate joint measurability; 3. Realisations offers in-depth studies of the fundamental observables of quantum mechanics and some of their measurement implementations; and 4....

  19. Quantum cryptography

    CERN Document Server

    Gilbert, Gerald; Hamrick, Michael

    2013-01-01

    This book provides a detailed account of the theory and practice of quantum cryptography. Suitable as the basis for a course in the subject at the graduate level, it crosses the disciplines of physics, mathematics, computer science and engineering. The theoretical and experimental aspects of the subject are derived from first principles, and attention is devoted to the practical development of realistic quantum communications systems. The book also includes a comprehensive analysis of practical quantum cryptography systems implemented in actual physical environments via either free-space or fiber-optic cable quantum channels. This book will be a valuable resource for graduate students, as well as professional scientists and engineers, who desire an introduction to the field that will enable them to undertake research in quantum cryptography. It will also be a useful reference for researchers who are already active in the field, and for academic faculty members who are teaching courses in quantum information s...

  20. Entropy inequalities from reflection positivity

    International Nuclear Information System (INIS)

    Casini, H

    2010-01-01

    We investigate the question of whether the entropy and the Renyi entropies of the vacuum state reduced to a region of space can be represented in terms of correlators in quantum field theory. In this case, the positivity relations for the correlators are mapped into inequalities for the entropies. We write them using a real-time version of reflection positivity, which can be generalized to general quantum systems. Using this generalization we can prove an infinite sequence of inequalities which are obeyed by the Renyi entropies of integer index. There is one independent inequality involving any number of different subsystems. In quantum field theory the inequalities acquire a simple geometrical form and are consistent with the integer index Renyi entropies being given by vacuum expectation values of twisting operators in the Euclidean formulation. Several possible generalizations and specific examples are analyzed

  1. Quantum foundations in the light of quantum cryptography

    International Nuclear Information System (INIS)

    Brassard, G.; Fuchs, C.A.

    2005-01-01

    Full text: Consider the two great physical theories of the twentieth century: relativity and quantum mechanics. Einstein derived relativity from very simple principles such as: 'The speed of light in empty space is independent of the speed of its source' and 'Physics should appear the same in all inertial reference frames'. By contrast, the foundation of quantum mechanics is built on a set of rather strange, disjointed and ad hoc axioms. Why is that? Must quantum mechanics be inherently less elegant than relativity? Or is it rather that the current axioms of quantum mechanics reflect at best the history that led to its discovery by too many people (compared to one person for relativity), over too long a period of time? The purpose of this talk is to argue that a better foundation for quantum mechanics lies within the teachings of quantum information science. We postulate that the truly fundamental laws of nature concern information, not waves or particles. For example, it has been proven, from the current axioms of quantum mechanics, that 'nature allows for the unconditionally secure transmission of confidential information', but 'nature does not allow for unconditionally secure bit commitment' (these are standard classical cryptographic primitives). We propose to turn the table around, start from these two theorems and possibly a few others, upgrade them as axioms, and ask how much of quantum mechanics they can derive. This provocative talk is meant as an eye-opener: we shall ask far more questions than we shall resolve. (author)

  2. Quantum Integers

    International Nuclear Information System (INIS)

    Khrennikov, Andrei; Klein, Moshe; Mor, Tal

    2010-01-01

    In number theory, a partition of a positive integer n is a way of writing n as a sum of positive integers. The number of partitions of n is given by the partition function p(n). Inspired by quantum information processing, we extend the concept of partitions in number theory as follows: for an integer n, we treat each partition as a basis state of a quantum system representing that number n, so that the Hilbert-space that corresponds to that integer n is of dimension p(n); the 'classical integer' n can thus be generalized into a (pure) quantum state ||ψ(n) > which is a superposition of the partitions of n, in the same way that a quantum bit (qubit) is a generalization of a classical bit. More generally, ρ(n) is a density matrix in that same Hilbert-space (a probability distribution over pure states). Inspired by the notion of quantum numbers in quantum theory (such as in Bohr's model of the atom), we then try to go beyond the partitions, by defining (via recursion) the notion of 'sub-partitions' in number theory. Combining the two notions mentioned above, sub-partitions and quantum integers, we finally provide an alternative definition of the quantum integers [the pure-state |ψ'(n)> and the mixed-state ρ'(n),] this time using the sub-partitions as the basis states instead of the partitions, for describing the quantum number that corresponds to the integer n.

  3. Quantum information

    CERN Document Server

    Barnett, Stephen M

    2009-01-01

    Quantum information- the subject- is a new and exciting area of science, which brings together physics, information theory, computer science and mathematics. "Quantum Information"- the book- is based on two successful lecture courses given to advanced undergraduate and beginning postgraduate students in physics. The intention is to introduce readers at this level to the fundamental, but offer rather simple, ideas behind ground-breaking developments including quantum cryptography,teleportation and quantum computing. The text is necessarily rather mathematical in style, but the mathema

  4. Quantum mechanics

    International Nuclear Information System (INIS)

    Basdevant, J.L.; Dalibard, J.; Joffre, M.

    2008-01-01

    All physics is quantum from elementary particles to stars and to the big-bang via semi-conductors and chemistry. This theory is very subtle and we are not able to explain it without the help of mathematic tools. This book presents the principles of quantum mechanics and describes its mathematical formalism (wave function, Schroedinger equation, quantum operators, spin, Hamiltonians, collisions,..). We find numerous applications in the fields of new technologies (maser, quantum computer, cryptography,..) and in astrophysics. A series of about 90 exercises with their answers is included. This book is based on a physics course at a graduate level. (A.C.)

  5. Quantum information

    International Nuclear Information System (INIS)

    Rodgers, P.

    1998-01-01

    There is more to information than a string of ones and zeroes the ability of ''quantum bits'' to be in two states at the same time could revolutionize information technology. In the mid-1930s two influential but seemingly unrelated papers were published. In 1935 Einstein, Podolsky and Rosen proposed the famous EPR paradox that has come to symbolize the mysteries of quantum mechanics. Two years later, Alan Turing introduced the universal Turing machine in an enigmatically titled paper, On computable numbers, and laid the foundations of the computer industry one of the biggest industries in the world today. Although quantum physics is essential to understand the operation of transistors and other solid-state devices in computers, computation itself has remained a resolutely classical process. Indeed it seems only natural that computation and quantum theory should be kept as far apart as possible surely the uncertainty associated with quantum theory is anathema to the reliability expected from computers? Wrong. In 1985 David Deutsch introduced the universal quantum computer and showed that quantum theory can actually allow computers to do more rather than less. The ability of particles to be in a superposition of more than one quantum state naturally introduces a form of parallelism that can, in principle, perform some traditional computing tasks faster than is possible with classical computers. Moreover, quantum computers are capable of other tasks that are not conceivable with their classical counterparts. Similar breakthroughs in cryptography and communication followed. (author)

  6. Quantum computation

    International Nuclear Information System (INIS)

    Deutsch, D.

    1992-01-01

    As computers become ever more complex, they inevitably become smaller. This leads to a need for components which are fabricated and operate on increasingly smaller size scales. Quantum theory is already taken into account in microelectronics design. This article explores how quantum theory will need to be incorporated into computers in future in order to give them their components functionality. Computation tasks which depend on quantum effects will become possible. Physicists may have to reconsider their perspective on computation in the light of understanding developed in connection with universal quantum computers. (UK)

  7. Quantum Dots

    Science.gov (United States)

    Tartakovskii, Alexander

    2012-07-01

    Part I. Nanostructure Design and Structural Properties of Epitaxially Grown Quantum Dots and Nanowires: 1. Growth of III/V semiconductor quantum dots C. Schneider, S. Hofling and A. Forchel; 2. Single semiconductor quantum dots in nanowires: growth, optics, and devices M. E. Reimer, N. Akopian, M. Barkelid, G. Bulgarini, R. Heeres, M. Hocevar, B. J. Witek, E. Bakkers and V. Zwiller; 3. Atomic scale analysis of self-assembled quantum dots by cross-sectional scanning tunneling microscopy and atom probe tomography J. G. Keizer and P. M. Koenraad; Part II. Manipulation of Individual Quantum States in Quantum Dots Using Optical Techniques: 4. Studies of the hole spin in self-assembled quantum dots using optical techniques B. D. Gerardot and R. J. Warburton; 5. Resonance fluorescence from a single quantum dot A. N. Vamivakas, C. Matthiesen, Y. Zhao, C.-Y. Lu and M. Atature; 6. Coherent control of quantum dot excitons using ultra-fast optical techniques A. J. Ramsay and A. M. Fox; 7. Optical probing of holes in quantum dot molecules: structure, symmetry, and spin M. F. Doty and J. I. Climente; Part III. Optical Properties of Quantum Dots in Photonic Cavities and Plasmon-Coupled Dots: 8. Deterministic light-matter coupling using single quantum dots P. Senellart; 9. Quantum dots in photonic crystal cavities A. Faraon, D. Englund, I. Fushman, A. Majumdar and J. Vukovic; 10. Photon statistics in quantum dot micropillar emission M. Asmann and M. Bayer; 11. Nanoplasmonics with colloidal quantum dots V. Temnov and U. Woggon; Part IV. Quantum Dot Nano-Laboratory: Magnetic Ions and Nuclear Spins in a Dot: 12. Dynamics and optical control of an individual Mn spin in a quantum dot L. Besombes, C. Le Gall, H. Boukari and H. Mariette; 13. Optical spectroscopy of InAs/GaAs quantum dots doped with a single Mn atom O. Krebs and A. Lemaitre; 14. Nuclear spin effects in quantum dot optics B. Urbaszek, B. Eble, T. Amand and X. Marie; Part V. Electron Transport in Quantum Dots Fabricated by

  8. Reflectance Modeling

    Science.gov (United States)

    Smith, J. A.; Cooper, K.; Randolph, M.

    1984-01-01

    A classical description of the one dimensional radiative transfer treatment of vegetation canopies was completed and the results were tested against measured prairie (blue grama) and agricultural canopies (soybean). Phase functions are calculated in terms of directly measurable biophysical characteristics of the canopy medium. While the phase functions tend to exhibit backscattering anisotropy, their exact behavior is somewhat more complex and wavelength dependent. A Monte Carlo model was developed that treats soil surfaces with large periodic variations in three dimensions. A photon-ray tracing technology is used. Currently, the rough soil surface is described by analytic functions and appropriate geometric calculations performed. A bidirectional reflectance distribution function is calculated and, hence, available for other atmospheric or canopy reflectance models as a lower boundary condition. This technique is used together with an adding model to calculate several cases where Lambertian leaves possessing anisotropic leaf angle distributions yield non-Lambertian reflectance; similar behavior is exhibited for simulated soil surfaces.

  9. Reflective optics

    CERN Document Server

    Korsch, Dietrich

    1991-01-01

    This is the first book dedicated exclusively to all-reflective imaging systems. It is a teaching tool as well as a practical design tool for anyone who specializes in optics, particularly for those interested in telescopes, infrared, and grazing-incidence systems. The first part of the book describes a unified geometric optical theory of all-reflective imaging systems (from near-normal to grazing incidence) developed from basic principles. The second part discusses correction methods and a multitude of closed-form solutions of well-corrected systems, supplemented with many conventional and unc

  10. Quantum computation with superconductors

    OpenAIRE

    Irastorza Gabilondo, Amaia

    2017-01-01

    Quantum computation using supercoducting qubits. Qubits are quantum bits used in quantum computers. Superconducting qubits are a strong option for building a quantum computer. But not just that, as they are macroscopic objects they question the limits of quantum physics.

  11. Black holes are almost optimal quantum cloners

    Science.gov (United States)

    Adami, Christoph; Ver Steeg, Greg

    2015-06-01

    If black holes were able to clone quantum states, a number of paradoxes in black hole physics would disappear. However, the linearity of quantum mechanics forbids exact cloning of quantum states. Here we show that black holes indeed clone incoming quantum states with a fidelity that depends on the black hole’s absorption coefficient, without violating the no-cloning theorem because the clones are only approximate. Perfectly reflecting black holes are optimal universal ‘quantum cloning machines’ and operate on the principle of stimulated emission, exactly as their quantum optical counterparts. In the limit of perfect absorption, the fidelity of clones is only equal to what can be obtained via quantum state estimation methods. But for any absorption probability less than one, the cloning fidelity is nearly optimal as long as ω /T≥slant 10, a common parameter for modest-sized black holes.

  12. Journeys into Inner/Outer Space: Reflections on the Methodological Challenges of Negotiating Insider/Outsider Status in International Educational Research

    Science.gov (United States)

    Savvides, Nicola; Al-Youssef, Joanna; Colin, Mindy; Garrido, Cecilia

    2014-01-01

    This article highlights key theoretical and methodological issues and implications of being an insider/outsider when undertaking qualitative research in international educational settings. It first addresses discourses of "self" and "other," noting that identity and belonging emerge from fluid engagement between researchers and…

  13. Does the School Performance Variable Used in the International Health Behavior in School-Aged Children (HBSC) Study Reflect Students' School Grades?

    Science.gov (United States)

    Felder-Puig, Rosemarie; Griebler, Robert; Samdal, Oddrun; King, Matthew A.; Freeman, John; Duer, Wolfgang

    2012-01-01

    Background: Given the pressure that educators and policy makers are under to achieve academic standards for students, understanding the relationship of academic success to various aspects of health is important. The international Health Behavior in School-Aged Children (HBSC) questionnaire, being used in 41 countries with different school and…

  14. Reflections on delivering a cross-discipline, cross-cultural, international, masters-level collaborative course using e-Learning technologies

    NARCIS (Netherlands)

    Leung, W.S.; Coulter, D.A.; Moes, C.C.M.; Horvath, I.

    2012-01-01

    This paper presents a case study on the experience of delivering an Internet-based international collaborative semester course at intermediate postgraduate level and attempts to distill a model for exploring the success factors involved when presenting such courses. The pedagogic and practical

  15. Quantum information. Teleportation - cryptography - quantum computer

    International Nuclear Information System (INIS)

    Koenneker, Carsten

    2012-01-01

    The following topics are dealt with: Reality in the test facility, quantum teleportation, the reality of quanta, interaction-free quantum measurement, rules for quantum computers, quantum computers with ions, spintronics with diamond, the limits of the quantum computers, a view in the future of quantum optics. (HSI)

  16. Personal Reflections

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 1. Jochen and Werner Heisenberg. Personal Reflections Volume 10 Issue 1 January 2005 pp 93-96. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/010/01/0093-0096. Resonance – Journal of ...

  17. PERSONAL REFLECTIONS

    Indian Academy of Sciences (India)

    IAS Admin

    Resonance journal of science education. April 2015 Volume 20 Number 4. GENERALARTICLES ... Development of. Probability Theory. K B Athreya. Classroom. Tutorial on Phyloge- netic Inference –1. Felix Bast. 360. 346. 286. PERSONAL REFLECTIONS. 368 The Road to IISc. M L Munjal (Transcribed by Maneesh Kunte).

  18. Quantum Physics Without Quantum Philosophy

    CERN Document Server

    Dürr, Detlef; Zanghì, Nino

    2013-01-01

    It has often been claimed that without drastic conceptual innovations a genuine explanation of quantum interference effects and quantum randomness is impossible. This book concerns Bohmian mechanics, a simple particle theory that is a counterexample to such claims. The gentle introduction and other contributions collected here show how the phenomena of non-relativistic quantum mechanics, from Heisenberg's uncertainty principle to non-commuting observables, emerge from the Bohmian motion of particles, the natural particle motion associated with Schrödinger's equation. This book will be of value to all students and researchers in physics with an interest in the meaning of quantum theory as well as to philosophers of science.

  19. Quantum ensembles of quantum classifiers.

    Science.gov (United States)

    Schuld, Maria; Petruccione, Francesco

    2018-02-09

    Quantum machine learning witnesses an increasing amount of quantum algorithms for data-driven decision making, a problem with potential applications ranging from automated image recognition to medical diagnosis. Many of those algorithms are implementations of quantum classifiers, or models for the classification of data inputs with a quantum computer. Following the success of collective decision making with ensembles in classical machine learning, this paper introduces the concept of quantum ensembles of quantum classifiers. Creating the ensemble corresponds to a state preparation routine, after which the quantum classifiers are evaluated in parallel and their combined decision is accessed by a single-qubit measurement. This framework naturally allows for exponentially large ensembles in which - similar to Bayesian learning - the individual classifiers do not have to be trained. As an example, we analyse an exponentially large quantum ensemble in which each classifier is weighed according to its performance in classifying the training data, leading to new results for quantum as well as classical machine learning.

  20. After Fukushima? On the educational and learning theoretical reflection of nuclear disasters. International perspectives; Nach Fukushima? Zur erziehungs- und bildungstheoretischen Reflexion atomarer Katastrophen. Internationale Perspektiven

    Energy Technology Data Exchange (ETDEWEB)

    Wigger, Lothar; Buenger, Carsten (eds.) [Technische Univ. Dortmund (Germany). Bereich Allgemeine Erziehungswissenschaft; Platzer, Barbara [Technische Univ. Dortmund (Germany)

    2017-08-01

    The book on the educational and learning theoretical reflection of nuclear disasters as a consequence of Fukushima includes contributions on the following issues: pedagogical approach: children write on Fukushima, description of the reality as pedagogical challenge; lessons learned on the nuclear technology - perspectives and limits of pedagogical evaluation: moral education - Japanese teaching materials, educational challenges at the universities with respect to nuclear technology and technology impact assessment; education and technology - questions concerning the pedagogical responsibility: considerations on the responsibility of scientists, on the discrepancy between technology and education, disempowerment of the public by structural corruption - nuclear disaster and post-democratic tendencies in Japan.

  1. Quantum Computing

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 9. Quantum Computing - Building Blocks of a Quantum Computer. C S Vijay Vishal Gupta. General Article Volume 5 Issue 9 September 2000 pp 69-81. Fulltext. Click here to view fulltext PDF. Permanent link:

  2. Quantum picturalism

    Science.gov (United States)

    Coecke, Bob

    2010-01-01

    Why did it take us 50 years since the birth of the quantum mechanical formalism to discover that unknown quantum states cannot be cloned? Yet, the proof of the 'no-cloning theorem' is easy, and its consequences and potential for applications are immense. Similarly, why did it take us 60 years to discover the conceptually intriguing and easily derivable physical phenomenon of 'quantum teleportation'? We claim that the quantum mechanical formalism doesn't support our intuition, nor does it elucidate the key concepts that govern the behaviour of the entities that are subject to the laws of quantum physics. The arrays of complex numbers are kin to the arrays of 0s and 1s of the early days of computer programming practice. Using a technical term from computer science, the quantum mechanical formalism is 'low-level'. In this review we present steps towards a diagrammatic 'high-level' alternative for the Hilbert space formalism, one which appeals to our intuition. The diagrammatic language as it currently stands allows for intuitive reasoning about interacting quantum systems, and trivialises many otherwise involved and tedious computations. It clearly exposes limitations such as the no-cloning theorem, and phenomena such as quantum teleportation. As a logic, it supports 'automation': it enables a (classical) computer to reason about interacting quantum systems, prove theorems, and design protocols. It allows for a wider variety of underlying theories, and can be easily modified, having the potential to provide the required step-stone towards a deeper conceptual understanding of quantum theory, as well as its unification with other physical theories. Specific applications discussed here are purely diagrammatic proofs of several quantum computational schemes, as well as an analysis of the structural origin of quantum non-locality. The underlying mathematical foundation of this high-level diagrammatic formalism relies on so-called monoidal categories, a product of a fairly

  3. Quantum Mechanics

    CERN Document Server

    Schwabl, Franz

    2007-01-01

    This represents the introductory course which would precede and so complements the author's book on Advanced Quantum Mechanics. The new edition has been up-dated and thoroughly revised throughout and now includes many new or newly drawn figures which will facilitate an easier understanding of subtle topics. The book meets students' needs in providing detailed mathematical steps along the way, with worked examples and applications throughout the text, and many problems for the reader at the end of each chapter. It contains nonrelativistic quantum mechanics and a short treatment of the quantization of the radiation field. In addition to the essentials, topics such as the theory of measurement, the Bell inequality, decoherence, entanglement and supersymmetric quantum mechanics are discussed. "Any student wishing to develop mathematical skills and deepen their understanding of the technical side of quantum theory will find Schwabl's Quantum Mechanics very helpful". Contemporary Physics

  4. Quantum mechanics

    CERN Document Server

    Rae, Alastair I M

    2016-01-01

    A Thorough Update of One of the Most Highly Regarded Textbooks on Quantum Mechanics Continuing to offer an exceptionally clear, up-to-date treatment of the subject, Quantum Mechanics, Sixth Edition explains the concepts of quantum mechanics for undergraduate students in physics and related disciplines and provides the foundation necessary for other specialized courses. This sixth edition builds on its highly praised predecessors to make the text even more accessible to a wider audience. It is now divided into five parts that separately cover broad topics suitable for any general course on quantum mechanics. New to the Sixth Edition * Three chapters that review prerequisite physics and mathematics, laying out the notation, formalism, and physical basis necessary for the rest of the book * Short descriptions of numerous applications relevant to the physics discussed, giving students a brief look at what quantum mechanics has made possible industrially and scientifically * Additional end-of-chapter problems with...

  5. Quantum gravity

    CERN Document Server

    Kiefer, Claus

    2012-01-01

    The search for a quantum theory of the gravitational field is one of the great open problems in theoretical physics. This book presents a self-contained discussion of the concepts, methods and applications that can be expected in such a theory. The two main approaches to its construction - the direct quantisation of Einstein's general theory of relativity and string theory - are covered. Whereas the first attempts to construct a viable theory for the gravitational field alone, string theory assumes that a quantum theory of gravity will be achieved only through a unification of all the interactions. However, both employ the general method of quantization of constrained systems, which is described together with illustrative examples relevant for quantum gravity. There is a detailed presentation of the main approaches employed in quantum general relativity: path-integral quantization, the background-field method and canonical quantum gravity in the metric, connection and loop formulations. The discussion of stri...

  6. Quantum photonics

    CERN Document Server

    Pearsall, Thomas P

    2017-01-01

    This textbook employs a pedagogical approach that facilitates access to the fundamentals of Quantum Photonics. It contains an introductory description of the quantum properties of photons through the second quantization of the electromagnetic field, introducing stimulated and spontaneous emission of photons at the quantum level. Schrödinger’s equation is used to describe the behavior of electrons in a one-dimensional potential. Tunneling through a barrier is used to introduce the concept of non­locality of an electron at the quantum level, which is closely-related to quantum confinement tunneling, resonant tunneling, and the origin of energy bands in both periodic (crystalline) and aperiodic (non-crystalline) materials. Introducing the concepts of reciprocal space, Brillouin zones, and Bloch’s theorem, the determination of electronic band structure using the pseudopotential method is presented, allowing direct computation of the band structures of most group IV, group III-V, and group II-VI semiconducto...

  7. Single-Shot Quantum Nondemolition Detection of Individual Itinerant Microwave Photons

    Science.gov (United States)

    Besse, Jean-Claude; Gasparinetti, Simone; Collodo, Michele C.; Walter, Theo; Kurpiers, Philipp; Pechal, Marek; Eichler, Christopher; Wallraff, Andreas

    2018-04-01

    Single-photon detection is an essential component in many experiments in quantum optics, but it remains challenging in the microwave domain. We realize a quantum nondemolition detector for propagating microwave photons and characterize its performance using a single-photon source. To this aim, we implement a cavity-assisted conditional phase gate between the incoming photon and a superconducting artificial atom. By reading out the state of this atom in a single shot, we reach an external (internal) photon-detection fidelity of 50% (71%), limited by transmission efficiency between the source and the detector (75%) and the coherence properties of the qubit. By characterizing the coherence and average number of photons in the field reflected off the detector, we demonstrate its quantum nondemolition nature. We envisage applications in generating heralded remote entanglement between qubits and for realizing logic gates between propagating microwave photons.

  8. Quantum computing

    International Nuclear Information System (INIS)

    Steane, Andrew

    1998-01-01

    The subject of quantum computing brings together ideas from classical information theory, computer science, and quantum physics. This review aims to summarize not just quantum computing, but the whole subject of quantum information theory. Information can be identified as the most general thing which must propagate from a cause to an effect. It therefore has a fundamentally important role in the science of physics. However, the mathematical treatment of information, especially information processing, is quite recent, dating from the mid-20th century. This has meant that the full significance of information as a basic concept in physics is only now being discovered. This is especially true in quantum mechanics. The theory of quantum information and computing puts this significance on a firm footing, and has led to some profound and exciting new insights into the natural world. Among these are the use of quantum states to permit the secure transmission of classical information (quantum cryptography), the use of quantum entanglement to permit reliable transmission of quantum states (teleportation), the possibility of preserving quantum coherence in the presence of irreversible noise processes (quantum error correction), and the use of controlled quantum evolution for efficient computation (quantum computation). The common theme of all these insights is the use of quantum entanglement as a computational resource. It turns out that information theory and quantum mechanics fit together very well. In order to explain their relationship, this review begins with an introduction to classical information theory and computer science, including Shannon's theorem, error correcting codes, Turing machines and computational complexity. The principles of quantum mechanics are then outlined, and the Einstein, Podolsky and Rosen (EPR) experiment described. The EPR-Bell correlations, and quantum entanglement in general, form the essential new ingredient which distinguishes quantum from

  9. Modeling soil moisture-reflectance

    OpenAIRE

    Muller, Etienne; Decamps, Henri

    2001-01-01

    International audience; Spectral information on soil is not easily available as vegetation and farm works prevent direct observation of soil responses. However, there is an increasing need to include soil reflectance values in spectral unmixing algorithms or in classification approaches. In most cases, the impact of soil moisture on the reflectance is unknown and therefore ignored. The objective of this study was to model reflectance changes due to soil moisture in a real field situation usin...

  10. The readability of international illustration of auditor’s report: An advanced reflection on the compromise between normative principles and linguistic requirements

    OpenAIRE

    Mondher Fakhfakh

    2015-01-01

    The independent auditors periodically publish reports that summarize the audit results. These reports reinforce the financial communication and reliability of accounting information. International Standards on Auditing (ISA) determine the content of audit reports and the quality of audit results. Theoretically, the audit standardization must model intelligible and clear reports for readers. Compliance with linguistic principles contributes to the improvement of the structure of audit reports....

  11. Constructivism Goes Quantum

    Directory of Open Access Journals (Sweden)

    Tatiana A. Alekseeva

    2016-01-01

    Full Text Available The article deals with the evolution of constructivist paradigm of international relations. The issue is of utmost importance in terms of the search for theoretical alternatives in the IR thinking. First, we are giving basic introduction of constructivism on the basis of historical and hermeneutical approaches. There is no doubt that the paradigm has faced different theoretical challenges and a lot of critics which has to be addressed. The authors reconsider some constructivist theories and notions in Alexander Wendt's works and the way Wendt tried to reinforce and reassure the constructivist paradigm. This allows us to claim that quantum turn in recent Wendt's work was almost inevitable. Second, the article attempts to answer a question whether the fundamentals of quantum physics are relevant when speaking about social and political processes. At first glance, quantum physics approach has nothing in common with the theory of politics and the theory of international relations. However, there are some grounds to believe that certain problem issues of the political science and IR theory are not deadlocks. In the second part of the article we use the unleashed and underestimated potential of analytical philosophy. To conclude, we believe that today there are more questions than answers but the quantum paradigm is expected to be the important part of the political studies and IR theory as well.

  12. Dynamics of quantum discord in a quantum critical environment

    International Nuclear Information System (INIS)

    Xi Zhengjun; Li Yongming; Lu Xiaoming; Sun Zhe

    2011-01-01

    We study the dynamics of quantum discord (QD) of two qubits independently coupled to an Ising spin chain in a transverse field, which exhibits a quantum phase transition. For this model, we drive the corresponding Kraus operators, obtain the analytic results of QD and compare the dynamics of QD with the dynamics of relative entropy of entanglement nearby the critical point. It is shown that the impact of the quantum criticality environment on QD can be concentrated in a very narrow region nearby the critical point, so it supplies an efficient way to detect the critical points. In the vicinity of the critical point, the evolution of QD is shown to be more complicated than that of entanglement. Furthermore, we find that separable states can also be used to reflect the quantum criticality of the environment.

  13. Generalization of secure quantum information exchange to quantum ...

    Indian Academy of Sciences (India)

    Quantum entanglement makes possible many quantum information processing tasks, which are otherwise impossible in classical information theory. Quantum entanglement is widely used in quantum information processing tasks such as quantum teleportation. [5], quantum cryptography [6], quantum superdense coding [7], ...

  14. Quantum hall effect. A perspective

    International Nuclear Information System (INIS)

    Aoki, Hideo

    2006-01-01

    Novel concepts and phenomena are emerging recently in the physics of quantum Hall effect. This article gives an overview, which starts from the fractional quantum Hall system viewed as an extremely strongly correlated system, and move on to present various phenomena involving internal degrees of freedom (spin and layer), non-equilibrium and optical properties, and finally the spinoff to anomalous Hall effect and the rotating Bose-Einstein condensate. (author)

  15. Quantum communication and information processing

    Science.gov (United States)

    Beals, Travis Roland

    Quantum computers enable dramatically more efficient algorithms for solving certain classes of computational problems, but, in doing so, they create new problems. In particular, Shor's Algorithm allows for efficient cryptanalysis of many public-key cryptosystems. As public key cryptography is a critical component of present-day electronic commerce, it is crucial that a working, secure replacement be found. Quantum key distribution (QKD), first developed by C.H. Bennett and G. Brassard, offers a partial solution, but many challenges remain, both in terms of hardware limitations and in designing cryptographic protocols for a viable large-scale quantum communication infrastructure. In Part I, I investigate optical lattice-based approaches to quantum information processing. I look at details of a proposal for an optical lattice-based quantum computer, which could potentially be used for both quantum communications and for more sophisticated quantum information processing. In Part III, I propose a method for converting and storing photonic quantum bits in the internal state of periodically-spaced neutral atoms by generating and manipulating a photonic band gap and associated defect states. In Part II, I present a cryptographic protocol which allows for the extension of present-day QKD networks over much longer distances without the development of new hardware. I also present a second, related protocol which effectively solves the authentication problem faced by a large QKD network, thus making QKD a viable, information-theoretic secure replacement for public key cryptosystems.

  16. Quantum physics

    International Nuclear Information System (INIS)

    Basdevant, J.L.; Dalibart, J.

    1997-01-01

    This pedagogical book gives an initiation to the principles and practice of quantum mechanics. A large part is devoted to experimental facts and to their analysis: concrete facts, phenomena and applications related to fundamental physics, elementary particles, astrophysics, high-technology, semi-conductors, micro-electronics and lasers. The book is divided in 22 chapters dealing with: quantum phenomena, wave function and Schroedinger equation, physical units and measurements, energy quantification of some simple systems, Hilbert space, Dirac formalism and quantum mechanics postulates, two-state systems and ammonia Maser principle, bands theory and crystals conductibility, commutation of observables, Stern and Gerlach experiment, approximation methods, kinetic momentum in quantum mechanics, first description of atoms, 1/2 spin formalism and magnetic resonance, Lagrangian, Hamiltonian and Lorentz force in quantum mechanics, addition of kinetic momenta and fine and hyper-fine structure of atomic lines, identical particle systems and Pauli principle, qualitative physics and scale of size of some microscopic and macroscopic phenomena, systems evolution, collisions and cross sections, invariance and conservation laws, quantum mechanics and astrophysics, and historical aspects of quantum mechanics. (J.S.)

  17. Quantum communications

    CERN Document Server

    Cariolaro, Gianfranco

    2015-01-01

    This book demonstrates that a quantum communication system using the coherent light of a laser can achieve performance orders of magnitude superior to classical optical communications Quantum Communications provides the Masters and PhD signals or communications student with a complete basics-to-applications course in using the principles of quantum mechanics to provide cutting-edge telecommunications. Assuming only knowledge of elementary probability, complex analysis and optics, the book guides its reader through the fundamentals of vector and Hilbert spaces and the necessary quantum-mechanical ideas, simply formulated in four postulates. A turn to practical matters begins with and is then developed by: ·         development of the concept of quantum decision, emphasizing the optimization of measurements to extract useful information from a quantum system; ·         general formulation of a transmitter–receiver system ·         particular treatment of the most popular quantum co...

  18. Quantum Computers and Quantum Computer Languages: Quantum Assembly Language and Quantum C Language

    OpenAIRE

    Blaha, Stephen

    2002-01-01

    We show a representation of Quantum Computers defines Quantum Turing Machines with associated Quantum Grammars. We then create examples of Quantum Grammars. Lastly we develop an algebraic approach to high level Quantum Languages using Quantum Assembly language and Quantum C language as examples.

  19. Quantum Computers and Quantum Computer Languages: Quantum Assembly Language and Quantum C

    OpenAIRE

    Blaha, Stephen

    2002-01-01

    We show a representation of Quantum Computers defines Quantum Turing Machines with associated Quantum Grammars. We then create examples of Quantum Grammars. Lastly we develop an algebraic approach to high level Quantum Languages using Quantum Assembly language and Quantum C language as examples.

  20. Quantum mechanics

    CERN Document Server

    Powell, John L

    2015-01-01

    Suitable for advanced undergraduates, this thorough text focuses on the role of symmetry operations and the essentially algebraic structure of quantum-mechanical theory. Based on courses in quantum mechanics taught by the authors, the treatment provides numerous problems that require applications of theory and serve to supplement the textual material.Starting with a historical introduction to the origins of quantum theory, the book advances to discussions of the foundations of wave mechanics, wave packets and the uncertainty principle, and an examination of the Schrödinger equation that includ

  1. Quantum mechanics

    International Nuclear Information System (INIS)

    Rae, A.I.M.

    1981-01-01

    This book, based on a thirty lecture course given to students at the beginning of their second year, covers the quantum mechanics required by physics undergraduates. Early chapters deal with wave mechanics, including a discussion of the energy states of the hydrogen atom. These are followed by a more formal development of the theory, leading to a discussion of some advanced applications and an introduction to the conceptual problems associated with quantum measurement theory. Emphasis is placed on the fundamentals of quantum mechanics. Problems are included at the end of each chapter. (U.K.)

  2. Quantum Optics

    CERN Document Server

    Garrison, J C

    2008-01-01

    Quantum optics, i.e. the interaction of individual photons with matter, began with the discoveries of Planck and Einstein, but in recent years it has expanded beyond pure physics to become an important driving force for technological innovation. This book serves the broader readership growing out of this development by starting with an elementary description of the underlying physics and then building up a more advanced treatment. The reader is led from the quantum theory of thesimple harmonic oscillator to the application of entangled states to quantum information processing. An equally impor

  3. Quantum chemistry

    CERN Document Server

    Lowe, John P

    1993-01-01

    Praised for its appealing writing style and clear pedagogy, Lowe's Quantum Chemistry is now available in its Second Edition as a text for senior undergraduate- and graduate-level chemistry students. The book assumes little mathematical or physical sophistication and emphasizes an understanding of the techniques and results of quantum chemistry, thus enabling students to comprehend much of the current chemical literature in which quantum chemical methods or concepts are used as tools. The book begins with a six-chapter introduction of standard one-dimensional systems, the hydrogen atom,

  4. Quantum mechanics

    CERN Document Server

    Chowdhury, Sujaul

    2014-01-01

    This book presents comprehensive account of the course for undergraduate students with thorough and complete calculations. The book has been written with the notion that a wave is associated with a material particle i.e. wave and particle coexist. Heisenberg's uncertainty principle has been described in light of this. A chapter is dedicated to mathematical structure of Quantum Mechanics followed by applications to one-dimensional (1D) problems. Orbital and general angular momentum are treated in two separate chapters, the latter also treats addition of angular momentum. Quantum theory of scattering, matrix formulation of Quantum Mechanics variational method and WKB approximation method have also been discussed.

  5. Public Participation and the Rights of the Child: Reflection on International Law Standards in the Legal System of the Russian Federation

    Directory of Open Access Journals (Sweden)

    Mariya Riekkinen

    2016-01-01

    Full Text Available This article deals with the much debated issue of children’s public participation from the perspective of legal practices in the Russian Federation. Having emerged at the level of national jurisdictions, the practice of engaging minors in decision-making processes on issues of public significance – or the practice of public participation of children – is stipulated by the UN Committee on the Rights of the Child, based on Article 12 of the UN Convention on the Rights of the Child. Public participation of minors implies that children have clearly defined opportunities to take part in decision-making processes concerning those political and public matters affecting their interests.Albeit limited by the clause “regarding the issues concerning them,” the claims for such participation are dictated by emerging standards of international law. The author has examined the process of devising these standards in Russian public law. Moreover, an analysis of the evolution of academic views on public participation of children in Russian legal scholarship is also included in this article.Relying extensively on the method of legal analysis and the comparative analysis of the conformity of national public law standards with respect to international law, the author proposes several legal amendments to the Federal law “On the Basic Guarantees of the Rights of the Child in the Russian Federation,” which would lead to anchoring more solidly the participatory right of minors in the legal system of the Russian Federation.

  6. 'It's something that I manage but it is not who I am': reflections on internalized stigma in individuals with bipolar disorder.

    Science.gov (United States)

    Michalak, Erin; Livingston, James D; Hole, Rachelle; Suto, Melinda; Hale, Sandra; Haddock, Candace

    2011-09-01

    Bipolar disorder (BD) is a complex chronic condition associated with substantial costs, both at a personal and societal level. Growing research indicates that experiences with stigma may play a significant role in contributing to the distress, disability, and poor quality of life (QoL) often experienced in people with BD. Here, we present a sub-set of findings from a qualitative study of self-management strategies utilized by high functioning Canadian individuals with BD. Specifically, we describe a theme relating to participants' experiences and understandings of internalized stigma. Descriptive qualitative methods were used including purposeful sampling and thematic analysis. High functioning individuals with BD type I or II (N = 32) completed quantitative scales to assess symptoms, functioning and QoL, and participated in an individual interview or focus group to discuss the self-management strategies that they use to maintain or regain wellness. Thematic analysis identified several themes, including one relating to internalized stigma. Within this, four additional themes were identified: stigma expectations and experiences, sense of self/identity, judicious disclosure, and moving beyond internalised stigma. One of the more unique aspects of the study is that it involves a participant sample that is managing well with their illness, which differs from the norm in biomedical research that typically focuses on pathology, problems and dysfunction.

  7. Optical quantum memory

    OpenAIRE

    Lvovsky, A. I.; Sanders, B. C.; Tittel, W.

    2010-01-01

    Quantum memory is important to quantum information processing in many ways: a synchronization device to match various processes within a quantum computer, an identity quantum gate that leaves any state unchanged, and a tool to convert heralded photons to photons-on-demand. In addition to quantum computing, quantum memory would be instrumental for the implementation of long-distance quantum communication using quantum repeaters. The importance of this basic quantum gate is exemplified by the m...

  8. Reflective Writing

    DEFF Research Database (Denmark)

    Ahrenkiel Jørgensen, Andriette

    2016-01-01

    In Breve fra min Have (Letters from my Garden), the Swedish landscape architect, Sven-Ingvar Andersson, produces dialogues about his garden to a wide circle of friends, colleagues, deceased and still living acquaintances such as Karen Blixen, Gertrude Stein, C. Th. Sørensen, Albrecht Dürer, Peter...... Høeg etetera. The dialogues work as a tool of reflection in terms of providing opportunity to examine his own beliefs, to explore the possible reasons for engaging in a particular activity. On the basis of Sven-Ingvar Andersson’s book a teaching program at the Aarhus School of Architecture provides...

  9. Inspiring Reflections

    DEFF Research Database (Denmark)

    Muchie, Mammo

    2011-01-01

    A numberof Chris Freeman's colleagues were asked to reflect on what they thought describes his life and work in a few words. Some of the colleagues replied including former SPRU students that were taught or supervised by Chris Freeman. Their views on what they thought were Chris Freeman's defining...... life is not free from fluctuations, cycles, disruptions, crises and destructions both human and ecological. Innovation research ought to position itself to address environmental, financial and economic crises. The third is innovation research for development by addressing not only poverty erdaication...

  10. Magnetospatial dispersion of semiconductor quantum wells

    Science.gov (United States)

    Kotova, L. V.; Kats, V. N.; Platonov, A. V.; Kochereshko, V. P.; André, R.; Golub, L. E.

    2018-03-01

    Polarization conversion of light reflected from quantum wells governed by both magnetic field and light propagation direction is observed. We demonstrate that the polarization conversion is caused by the magnetospatial dispersion in quantum wells which manifests itself in the reflection coefficient contribution bilinear in the in-plane components of the magnetic field and the light wave vector. The magnetospatial dispersion is shown to arise due to structure inversion asymmetry of the quantum wells. The effect is resonantly enhanced in the vicinity of the heavy-hole exciton. We show that microscopically the magnetospatial dispersion is caused by the mixing of heavy- and light-hole states in the quantum well due to both orbital effect of the magnetic field and the in-plane hole motion. The degree of the structure inversion asymmetry is determined for GaAs/AlGaAs and CdTe quantum wells.

  11. The fragility of identity: about the internal experience of gender in Law N° 26.743 Reflections from Pierre Bourdieu and Judith Butler

    Directory of Open Access Journals (Sweden)

    Lucía Inés Coppa

    2014-12-01

    Full Text Available The following article intends to approach some aspects of bourdiean thoughts in order to develop an approach to the notion of gender and the way in which – within an androcentric symbolic order and a normative heterosexual matrix – function these diagrams in the way gender makes up the subjective corporal form. From those notions, we want to reflect about the emergency of sexual identities that transgress the cultural precepts around gender founded in doxic experience. Likewise, we will sketch a brief reference among inconscient dimension across psychoanalytical tradition and performative theory across Judith Butler in the feminists debates.Through this conceptual framework we will attempt to examine how may the dominant representations of femininity, androcentric and heterosexually regulated, influence the identity formation of a feminine transsexual person, founded in the morphological ideal which has sustenance in the man-woman dichotomy, leaving the questioning open about the ways that the transgressive assumption of sex of what appears like the order of things may take in a binomic gender matrix, examining the reception of this debates in te Gender Identity Law N° 26.743

  12. More terminological clarity in the interprofessional field – a call for reflection on the use of terminologies, in both practice and research, on a national and international level

    Directory of Open Access Journals (Sweden)

    Mitzkat, Anika

    2016-04-01

    Full Text Available The terminology which has been used up until now within interprofessional healthcare has been characterised by a certain definitional weakness, which, among other factors, has been caused by an uncritical adoption of language conventions and a lack of theoretical reflection. However, as terminological clarity plays a significant role in the development and profiling of a discipline, the clarification and definition of commonly-used terminology has manifested itself as a considerable objective for the interprofessional research community. One of the most important journals for research in the area of interprofessional education and care, the Journal of Interprofessional Care, has expanded its author guidelines relating to terminology, modeled after the conceptual considerations of the research group around Barr et. al and Reeves et al. A German translation of the suggested terms therein has been presented in this contribution, and discussed in light of the challenges to a possible adaptation for the German-speaking world. The objective is to assist communication in practice and research in becoming clearer, while promoting an increasing awareness to and the transparency of determined definitions and terminologies.

  13. More terminological clarity in the interprofessional field - a call for reflection on the use of terminologies, in both practice and research, on a national and international level.

    Science.gov (United States)

    Mitzkat, Anika; Berger, Sarah; Reeves, Scott; Mahler, Cornelia

    2016-01-01

    The terminology which has been used up until now within interprofessional healthcare has been characterised by a certain definitional weakness, which, among other factors, has been caused by an uncritical adoption of language conventions and a lack of theoretical reflection. However, as terminological clarity plays a significant role in the development and profiling of a discipline, the clarification and definition of commonly-used terminology has manifested itself as a considerable objective for the interprofessional research community. One of the most important journals for research in the area of interprofessional education and care, the Journal of Interprofessional Care, has expanded its author guidelines relating to terminology, modeled after the conceptual considerations of the research group around Barr et. al and Reeves et al. A German translation of the suggested terms therein has been presented in this contribution, and discussed in light of the challenges to a possible adaptation for the German-speaking world. The objective is to assist communication in practice and research in becoming clearer, while promoting an increasing awareness to and the transparency of determined definitions and terminologies.

  14. Realizing Controllable Quantum States

    Science.gov (United States)

    Takayanagi, Hideaki; Nitta, Junsaku

    1. Entanglement in solid states. Orbital entanglement and violation of bell inequalities in mesoscopic conductors / M. Büttiker, P. Samuelsson and E. V. Sukhoruk. Teleportation of electron spins with normal and superconducting dots / O. Sauret, D. Feinberg and T. Martin. Entangled state analysis for one-dimensional quantum spin system: singularity at critical point / A. Kawaguchi and K. Shimizu. Detecting crossed Andreev reflection by cross-current correlations / G. Bignon et al. Current correlations and transmission probabilities for a Y-shaped diffusive conductor / S. K. Yip -- 2. Mesoscopic electronics. Quantum bistability, structural transformation, and spontaneous persistent currents in mesoscopic Aharonov-Bohm loops / I. O. Kulik. Many-body effects on tunneling of electrons in magnetic-field-induced quasi one-dimensional systems in quantum wells / T. Kubo and Y. Tokura. Electron transport in 2DEG narrow channel under gradient magnetic field / M. Hara et al. Transport properties of a quantum wire with a side-coupled quantum dot / M. Yamaguchi et al. Photoconductivity- and magneto-transport studies of single InAs quantum wires / A. Wirthmann et al. Thermoelectric transports in charge-density-wave systems / H. Yoshimoto and S. Kurihara -- 3. Mesoscopic superconductivity. Parity-restricted persistent currents in SNS nanorings / A. D. Zaikin and S. V. Sharov. Large energy dependence of current noise in superconductingh/normal metal junctions / F. Pistolesi and M. Houzet. Generation of photon number states and their superpositions using a superconducting qubit in a microcavity / Yu-Xi Liu, L. F. Wei and F. Nori. Andreev interferometry for pumped currents / F. Taddei, M. Governale and R. Fazio. Suppression of Cooper-pair breaking against high magnetic fields in carbon nanotubes / J. Haruyama et al. Impact of the transport supercurrent on the Josephson effect / S. N. Shevchenko. Josephson current through spin-polarized Luttinger liquid / N. Yokoshi and S. Kurihara

  15. Quantum exam

    International Nuclear Information System (INIS)

    Nguyen, Ba An

    2006-01-01

    Absolutely and asymptotically secure protocols for organizing an exam in a quantum way are proposed basing judiciously on multipartite entanglement. The protocols are shown to stand against common types of eavesdropping attack

  16. Quantum computers.

    Science.gov (United States)

    Ladd, T D; Jelezko, F; Laflamme, R; Nakamura, Y; Monroe, C; O'Brien, J L

    2010-03-04

    Over the past several decades, quantum information science has emerged to seek answers to the question: can we gain some advantage by storing, transmitting and processing information encoded in systems that exhibit unique quantum properties? Today it is understood that the answer is yes, and many research groups around the world are working towards the highly ambitious technological goal of building a quantum computer, which would dramatically improve computational power for particular tasks. A number of physical systems, spanning much of modern physics, are being developed for quantum computation. However, it remains unclear which technology, if any, will ultimately prove successful. Here we describe the latest developments for each of the leading approaches and explain the major challenges for the future.

  17. Quantum Noise

    International Nuclear Information System (INIS)

    Beenakker, C W J

    2005-01-01

    Quantum Noise is advertised as a handbook, and this is indeed how it functions for me these days: it is a book that I keep within hand's reach, ready to be consulted on the proper use of quantum stochastic methods in the course of my research on quantum dots. I should point out that quantum optics, the target field for this book, is not my field by training. So I have much to learn, and find this handbook to be a reliable and helpful guide. Crispin Gardiner previously wrote the Handbook of Stochastic Methods (also published by Springer), which provides an overview of methods in classical statistical physics. Quantum Noise, written jointly with Peter Zoller, is the counterpart for quantum statistical physics, and indeed the two books rely on each other by frequent cross referencing. The fundamental problem addressed by Quantum Noise is how the quantum dynamics of an open system can be described statistically by treating the environment as a source of noise. This is a general problem in condensed matter physics (in particular in the context of Josephson junctions) and in quantum optics. The emphasis in this book in on the optical applications (for condensed matter applications one could consult Quantum Dissipative Systems by Ulrich Weiss, published by World Scientific). The optical applications centre around the interaction of light with atoms, where the atoms represent the open system and the light is the noisy environment. A complete description of the production and detection of non-classical states of radiation (such as squeezed states) can be obtained using one of the equivalent quantum stochastic formulations: the quantum Langevin equation for the field operators (in either the Ito or the Stratonovich form), the Master equation for the density matrix, or the stochastic Schroedinger equation for the wave functions. Each formulation is fully developed here (as one would expect from a handbook), with detailed instructions on how to go from one to the other. The

  18. Quantum Correlations Evolution Asymmetry in Quantum Channels

    International Nuclear Information System (INIS)

    Li Meng; Huang Yun-Feng; Guo Guang-Can

    2017-01-01

    It was demonstrated that the entanglement evolution of a specially designed quantum state in the bistochastic channel is asymmetric. In this work, we generalize the study of the quantum correlations, including entanglement and quantum discord, evolution asymmetry to various quantum channels. We found that the asymmetry of entanglement and quantum discord only occurs in some special quantum channels, and the behavior of the entanglement evolution may be quite different from the behavior of the quantum discord evolution. To quantum entanglement, in some channels it decreases monotonously with the increase of the quantum channel intensity. In some other channels, when we increase the intensity of the quantum channel, it decreases at first, then keeps zero for some time, and then rises up. To quantum discord, the evolution becomes more complex and you may find that it evolutes unsmoothly at some points. These results illustrate the strong dependence of the quantum correlations evolution on the property of the quantum channels. (paper)

  19. Partial quantum logics revisited

    Science.gov (United States)

    Vetterlein, Thomas

    2011-01-01

    Partial Boolean algebras (PBAs) were introduced by Kochen and Specker as an algebraic model reflecting the mutual relationships among quantum-physical yes-no tests. The fact that not all pairs of tests are compatible was taken into special account. In this paper, we review PBAs from two sides. First, we generalise the concept, taking into account also those yes-no tests which are based on unsharp measurements. Namely, we introduce partial MV-algebras, and we define a corresponding logic. Second, we turn to the representation theory of PBAs. In analogy to the case of orthomodular lattices, we give conditions for a PBA to be isomorphic to the PBA of closed subspaces of a complex Hilbert space. Hereby, we do not restrict ourselves to purely algebraic statements; we rather give preference to conditions involving automorphisms of a PBA. We conclude by outlining a critical view on the logico-algebraic approach to the foundational problem of quantum physics.

  20. Quantum lottery

    CERN Multimedia

    CERN Bulletin

    2013-01-01

    On April Fools' Day, CERN Quantum Diaries blogger Pauline Gagnon held a giveaway of microscopic proportion. Up for grabs? Ten Higgs bosons, courtesy of CERN. Pauline announced the winners last week; let's see what they'll really be getting in the mail...   Custom-made Particle Zoo Higgs bosons were sent out to the winners. Read more about the prize in the Quantum Diaries post "Higgs boson lottery: when CERN plays April Fools' jokes".

  1. Quantum optics

    DEFF Research Database (Denmark)

    Andersen, Ulrik Lund

    2013-01-01

    Further sensitivity improvements are required before advanced optical interferometers will be able to measure gravitational waves. A team has now shown that introducing quantum squeezing of light may help to detect these elusive waves.......Further sensitivity improvements are required before advanced optical interferometers will be able to measure gravitational waves. A team has now shown that introducing quantum squeezing of light may help to detect these elusive waves....

  2. Quantum entanglement and quantum computational algorithms

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 56; Issue 2-3. Quantum entanglement ... Arvind. Quantum information processing Volume 56 Issue 2-3 February-March 2001 pp 357-365 ... The existence of entangled quantum states gives extra power to quantum computers over their classical counterparts. Quantum ...

  3. Quantum Computation and Quantum Spin Dynamics

    NARCIS (Netherlands)

    Raedt, Hans De; Michielsen, Kristel; Hams, Anthony; Miyashita, Seiji; Saito, Keiji

    2001-01-01

    We analyze the stability of quantum computations on physically realizable quantum computers by simulating quantum spin models representing quantum computer hardware. Examples of logically identical implementations of the controlled-NOT operation are used to demonstrate that the results of a quantum

  4. Quantum entanglement

    International Nuclear Information System (INIS)

    Hadjiivanov, L.; Todorov, I.

    2015-01-01

    Expository paper providing a historical survey of the gradual transformation of the 'philosophical discussions' between Bohr, Einstein and Schrödinger on foundational issues in quantum mechanics into a quantitative prediction of a new quantum effect, its experimental verification and its proposed (and loudly advertised) applications. The basic idea of the 1935 paper of Einstein-Podolsky-Rosen (EPR) was reformulated by David Bohm for a finite dimensional spin system. This allowed John Bell to derive his inequalities that separate the prediction of quantum entanglement from its possible classical interpretation. We reproduce here their later (1971) version, reviewing on the way the generalization (and mathematical derivation) of Heisenberg's uncertainty relations (due to Weyl and Schrödinger) needed for the passage from EPR to Bell. We also provide an improved derivation of the quantum theoretic violation of Bell's inequalities. Soon after the experimental confirmation of the quantum entanglement (culminating with the work of Alain Aspect) it was Feynman who made public the idea of a quantum computer based on the observed effect

  5. International law

    CERN Document Server

    Shaw, Malcolm N

    2017-01-01

    International Law is the definitive and authoritative text on the subject, offering Shaw's unbeatable combination of clarity of expression and academic rigour and ensuring both understanding and critical analysis in an engaging and authoritative style. Encompassing the leading principles, practice and cases, and retaining and developing the detailed references which encourage and assist the reader in further study, this new edition motivates and challenges students and professionals while remaining accessible and engaging. Fully updated to reflect recent case law and treaty developments, this edition contains an expanded treatment of the relationship between international and domestic law, the principles of international humanitarian law, and international criminal law alongside additional material on international economic law.

  6. Fixed point algebras for easy quantum groups

    DEFF Research Database (Denmark)

    Gabriel, Olivier; Weber, Moritz

    2016-01-01

    Compact matrix quantum groups act naturally on Cuntz algebras. The first author isolated certain conditions under which the fixed point algebras under this action are Kirchberg algebras. Hence they are completely determined by their K-groups. Building on prior work by the second author,we prove...... that free easy quantum groups satisfy these conditions and we compute the K-groups of their fixed point algebras in a general form. We then turn to examples such as the quantum permutation group S+ n,the free orthogonal quantum group O+ n and the quantum reflection groups Hs+ n. Our fixed point......-algebra construction provides concrete examples of free actions of free orthogonal easy quantum groups,which are related to Hopf-Galois extensions....

  7. Do measures used in studies of anxiety disorders reflect activities and participation as defined in the WHO International Classification of Functioning, Disability and Health?

    Science.gov (United States)

    Brütt, Anna Levke; Schulz, Holger; Koch, Uwe; Andreas, Sylke

    2011-07-01

    Besides the measurement of symptoms, information on functioning and disability in daily routines expands the description of impairments in patients with anxiety disorders. Therefore, the measurement of activities and participation, as theoretically included in the International Classification of Functioning, Disability and Health (ICF) is of increasing importance. The objective of this study is to give an overview over the implementation of the concept 'activities and participation' in outcome measurements of patients with anxiety disorders. Based on a literature review in PubMed and PsycInfo databases and including 200 papers, this study analyses 65 outcome instruments used in randomized controlled trials in anxiety disorders according to their content related to the ICF domain of 'Activities and participation'. Instruments used in trials evaluating outcome in patients with anxiety disorder only partially address activities and participation. Over all 65 instruments, the chapters on 'Interpersonal interactions and relationships' and 'Mobility' were most frequently included in measurements. The identification of relevant ICF categories (core sets) according to activities and participation and especially interpersonal interactions and relationships as well as mobility, can be a basis for describing functioning and evaluating treatment in anxiety disorders, helping to improve outcome assessment in clinical practice.

  8. Quantum computing: Quantum advantage deferred

    Science.gov (United States)

    Childs, Andrew M.

    2017-12-01

    A type of optics experiment called a boson sampler could be among the easiest routes to demonstrating the power of quantum computers. But recent work shows that super-classical boson sampling may be a long way off.

  9. Beyond quantum microcanonical statistics

    International Nuclear Information System (INIS)

    Fresch, Barbara; Moro, Giorgio J.

    2011-01-01

    Descriptions of molecular systems usually refer to two distinct theoretical frameworks. On the one hand the quantum pure state, i.e., the wavefunction, of an isolated system is determined to calculate molecular properties and their time evolution according to the unitary Schroedinger equation. On the other hand a mixed state, i.e., a statistical density matrix, is the standard formalism to account for thermal equilibrium, as postulated in the microcanonical quantum statistics. In the present paper an alternative treatment relying on a statistical analysis of the possible wavefunctions of an isolated system is presented. In analogy with the classical ergodic theory, the time evolution of the wavefunction determines the probability distribution in the phase space pertaining to an isolated system. However, this alone cannot account for a well defined thermodynamical description of the system in the macroscopic limit, unless a suitable probability distribution for the quantum constants of motion is introduced. We present a workable formalism assuring the emergence of typical values of thermodynamic functions, such as the internal energy and the entropy, in the large size limit of the system. This allows the identification of macroscopic properties independently of the specific realization of the quantum state. A description of material systems in agreement with equilibrium thermodynamics is then derived without constraints on the physical constituents and interactions of the system. Furthermore, the canonical statistics is recovered in all generality for the reduced density matrix of a subsystem.

  10. Quantum Transmemetic Intelligence

    Science.gov (United States)

    Piotrowski, Edward W.; Sładkowski, Jan

    The following sections are included: * Introduction * A Quantum Model of Free Will * Quantum Acquisition of Knowledge * Thinking as a Quantum Algorithm * Counterfactual Measurement as a Model of Intuition * Quantum Modification of Freud's Model of Consciousness * Conclusion * Acknowledgements * References

  11. Quantum Physics for Beginners.

    Science.gov (United States)

    Strand, J.

    1981-01-01

    Suggests a new approach for teaching secondary school quantum physics. Reviews traditional approaches and presents some characteristics of the three-part "Quantum Physics for Beginners" project, including: quantum physics, quantum mechanics, and a short historical survey. (SK)

  12. Influence of strain in the reduction of the internal electric field in GaN/AlN quantum dots grown on a-plane 6H-SiC

    Energy Technology Data Exchange (ETDEWEB)

    Cros, A.; Budagosky, J.A.; Garcia-Cristobal, A.; Garro, N.; Cantarero, A. [Institut de Ciencia dels Materials, Universitat de Valencia, 46071 Valencia (Spain); Founta, S.; Mariette, H.; Daudin, B. [CEA-CNRS Group ' ' Nanophysique et Semiconducteurs' ' , Departement de Recherche Fondamentale sur la Matiere Condensee, CEA Grenoble, 17 rue des Martyrs, 38054 Grenoble (France)

    2006-06-15

    The strain state of stacks of GaN/AlN quantum dots (QDs) grown on (0001) and (11 anti 20) 6H-SiC has been investigated by means of Raman spectroscopy. Depending on the orientation of the wurtzite axis with respect to the growth direction it is found that the piezoelectric contribution to the electrostatic potential may either reinforce that arising from the spontaneous polarization or oppose it. The experimental results are compared with a theoretical model for the strain and polarization field in QDs of both orientations that allows the calculation of the electrostatic potential in the QDs. Both the experimental results and the theoretical model indicate that the internal electric field and electrostatic potential are strongly reduced in the QDs grown on (11 anti 20) 6H-SiC as compared to those grown along the wurtzite c-axis. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  13. Quantum Mechanics

    Science.gov (United States)

    Mandl, F.

    1992-07-01

    The Manchester Physics Series General Editors: D. J. Sandiford; F. Mandl; A. C. Phillips Department of Physics and Astronomy, University of Manchester Properties of Matter B. H. Flowers and E. Mendoza Optics Second Edition F. G. Smith and J. H. Thomson Statistical Physics Second Edition F. Mandl Electromagnetism Second Edition I. S. Grant and W. R. Phillips Statistics R. J. Barlow Solid State Physics Second Edition J. R. Hook and H. E. Hall Quantum Mechanics F. Mandl Particle Physics Second Edition B. R. Martin and G. Shaw The Physics of Stars Second Edition A. C. Phillips Computing for Scientists R. J. Barlow and A. R. Barnett Quantum Mechanics aims to teach those parts of the subject which every physicist should know. The object is to display the inherent structure of quantum mechanics, concentrating on general principles and on methods of wide applicability without taking them to their full generality. This book will equip students to follow quantum-mechanical arguments in books and scientific papers, and to cope with simple cases. To bring the subject to life, the theory is applied to the all-important field of atomic physics. No prior knowledge of quantum mechanics is assumed. However, it would help most readers to have met some elementary wave mechanics before. Primarily written for students, it should also be of interest to experimental research workers who require a good grasp of quantum mechanics without the full formalism needed by the professional theorist. Quantum Mechanics features: A flow diagram allowing topics to be studied in different orders or omitted altogether. Optional "starred" and highlighted sections containing more advanced and specialized material for the more ambitious reader. Sets of problems at the end of each chapter to help student understanding. Hints and solutions to the problems are given at the end of the book.

  14. Robust quantum memory via quantum control

    OpenAIRE

    Greentree, Andrew D.; Schirmer, S. G.; Solomon, A. I.

    2001-01-01

    A general scheme for building a quantum memory by transferring quantum information to an essentially decoherence-free memory transition using quantum control is presented and illustrated by computer simulations.

  15. Reflected Glory

    Science.gov (United States)

    2011-02-01

    The nebula Messier 78 takes centre stage in this image taken with the Wide Field Imager on the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile, while the stars powering the bright display take a backseat. The brilliant starlight ricochets off dust particles in the nebula, illuminating it with scattered blue light. Igor Chekalin was the overall winner of ESO's Hidden Treasures 2010 astrophotography competition with his image of this stunning object. Messier 78 is a fine example of a reflection nebula. The ultraviolet radiation from the stars that illuminate it is not intense enough to ionise the gas to make it glow - its dust particles simply reflect the starlight that falls on them. Despite this, Messier 78 can easily be observed with a small telescope, being one of the brightest reflection nebulae in the sky. It lies about 1350 light-years away in the constellation of Orion (The Hunter) and can be found northeast of the easternmost star of Orion's belt. This new image of Messier 78 from the MPG/ESO 2.2-metre telescope at the La Silla Observatory is based on data selected by Igor Chekalin in his winning entry to the Hidden Treasures competition [1]. The pale blue tint seen in the nebula in this picture is an accurate representation of its dominant colour. Blue hues are commonly seen in reflection nebulae because of the way the starlight is scattered by the tiny dust particles that they contain: the shorter wavelength of blue light is scattered more efficiently than the longer wavelength red light. This image contains many other striking features apart from the glowing nebula. A thick band of obscuring dust stretches across the image from the upper left to the lower right, blocking the light from background stars. In the bottom right corner, many curious pink structures are also visible, which are created by jets of material being ejected from stars that have recently formed and are still buried deep in dust clouds. Two bright stars, HD 38563A and

  16. Long distance quantum teleportation

    Science.gov (United States)

    Xia, Xiu-Xiu; Sun, Qi-Chao; Zhang, Qiang; Pan, Jian-Wei

    2018-01-01

    Quantum teleportation is a core protocol in quantum information science. Besides revealing the fascinating feature of quantum entanglement, quantum teleportation provides an ultimate way to distribute quantum state over extremely long distance, which is crucial for global quantum communication and future quantum networks. In this review, we focus on the long distance quantum teleportation experiments, especially those employing photonic qubits. From the viewpoint of real-world application, both the technical advantages and disadvantages of these experiments are discussed.

  17. Gaussian Hypothesis Testing and Quantum Illumination.

    Science.gov (United States)

    Wilde, Mark M; Tomamichel, Marco; Lloyd, Seth; Berta, Mario

    2017-09-22

    Quantum hypothesis testing is one of the most basic tasks in quantum information theory and has fundamental links with quantum communication and estimation theory. In this paper, we establish a formula that characterizes the decay rate of the minimal type-II error probability in a quantum hypothesis test of two Gaussian states given a fixed constraint on the type-I error probability. This formula is a direct function of the mean vectors and covariance matrices of the quantum Gaussian states in question. We give an application to quantum illumination, which is the task of determining whether there is a low-reflectivity object embedded in a target region with a bright thermal-noise bath. For the asymmetric-error setting, we find that a quantum illumination transmitter can achieve an error probability exponent stronger than a coherent-state transmitter of the same mean photon number, and furthermore, that it requires far fewer trials to do so. This occurs when the background thermal noise is either low or bright, which means that a quantum advantage is even easier to witness than in the symmetric-error setting because it occurs for a larger range of parameters. Going forward from here, we expect our formula to have applications in settings well beyond those considered in this paper, especially to quantum communication tasks involving quantum Gaussian channels.

  18. Quantum bit commitment protocol without quantum memory

    OpenAIRE

    Ramos, Rubens Viana; Mendonca, Fabio Alencar

    2008-01-01

    Quantum protocols for bit commitment have been proposed and it is largely accepted that unconditionally secure quantum bit commitment is not possible; however, it can be more secure than classical bit commitment. In despite of its usefulness, quantum bit commitment protocols have not been experimentally implemented. The main reason is the fact that all proposed quantum bit commitment protocols require quantum memory. In this work, we show a quantum bit commitment protocol that does not requir...

  19. Globalization as a Driver or Bottleneck for Sustainable Development: Some Empirical, Cross-National Reflections on Basic Issues of International Health Policy and Management

    Science.gov (United States)

    Tausch, Arno

    2013-01-01

    Background: This article looks at the long-term, structural determinants of environmental and public health performance in the world system. Methods: In multiple standard ordinary least squares (OLS) regression models, we tested the effects of 26 standard predictor variables, including the ‘four freedoms’ of goods, capital, labour and services, on the following indicators of sustainable development and public health: avoiding net trade of ecological footprint global hectare (gha) per person; avoiding high carbon emissions per million US dollars GDP; avoiding high CO2 per capita (gha/cap); avoiding high ecological footprint per capita; avoiding becoming victim of natural disasters; a good performance on the Environmental Performance Index (EPI); a good performance on the Happy Life Years (HLYs) scale; and a good performance on the Happy Planet Index (HPI). Results: Our research showed that the apprehensions of quantitative research, critical of neo-liberal globalization, are fully vindicated by the significant negative environmental and public health effects of the foreign savings rate. High foreign savings are indeed a driver of global footprint, and are a blockade against a satisfactory HPI performance. The new international division of labour is one of the prime drivers of high CO2 per capita emissions. Multinational Corporation (MNC) penetration, the master variable of most quantitative dependency theories, blocks EPI and several other socially important processes. Worker remittances have a significant positive effect on the HPI, and HLYs. Conclusion: We re-analysed the solid macro-political and macro-sociological evidence on a global scale, published in the world’s leading peer-reviewed social science, ecological and public health journals, which seem to indicate that there are contradictions between unfettered globalization and unconstrained world economic openness and sustainable development and public health development. We suggest that there seems to

  20. Globalization as a driver or bottleneck for sustainable development: some empirical, cross-national reflections on basic issues of international health policy and management.

    Science.gov (United States)

    Tausch, Arno

    2013-08-01

    This article looks at the long-term, structural determinants of environmental and public health performance in the world system. In multiple standard ordinary least squares (OLS) regression models, we tested the effects of 26 standard predictor variables, including the 'four freedoms' of goods, capital, labour and services, on the following indicators of sustainable development and public health: avoiding net trade of ecological footprint global hectare (gha) per person; avoiding high carbon emissions per million US dollars GDP; avoiding high CO2 per capita (gha/cap); avoiding high ecological footprint per capita; avoiding becoming victim of natural disasters; a good performance on the Environmental Performance Index (EPI); a good performance on the Happy Life Years (HLYs) scale; and a good performance on the Happy Planet Index (HPI). Our research showed that the apprehensions of quantitative research, critical of neo-liberal globalization, are fully vindicated by the significant negative environmental and public health effects of the foreign savings rate. High foreign savings are indeed a driver of global footprint, and are a blockade against a satisfactory HPI performance. The new international division of labour is one of the prime drivers of high CO2 per capita emissions. Multinational Corporation (MNC) penetration, the master variable of most quantitative dependency theories, blocks EPI and several other socially important processes. Worker remittances have a significant positive effect on the HPI, and HLYs. We re-analysed the solid macro-political and macro-sociological evidence on a global scale, published in the world's leading peer-reviewed social science, ecological and public health journals, which seem to indicate that there are contradictions between unfettered globalization and unconstrained world economic openness and sustainable development and public health development. We suggest that there seems to be a strong interaction between 'transnational

  1. Globalization as a Driver or Bottleneck for Sustainable Development: Some Empirical, Cross-National Reflections on Basic Issues of International Health Policy and Management

    Directory of Open Access Journals (Sweden)

    Arno Tausch

    2013-01-01

    Full Text Available BackgroundThis article looks at the long-term, structural determinants of environmental and public health performance in the world system. MethodsIn multiple standard ordinary least squares (OLS regression models, we tested the effects of 26 standard predictor variables, including the ‘four freedoms’ of goods, capital, labour and services, on the following indicators of sustainable development and public health: avoiding net trade of ecological footprint global hectare (gha per person; avoiding high carbon emissions per million US dollars GDP; avoiding high CO2 per capita (gha/cap; avoiding high ecological footprint per capita; avoiding becoming victim of natural disasters; a good performance on the Environmental Performance Index (EPI; a good performance on the Happy Life Years (HLYs scale; and a good performance on the Happy Planet Index (HPI. ResultsOur research showed that the apprehensions of quantitative research, critical of neo-liberal globalization, are fully vindicated by the significant negative environmental and public health effects of the foreign savings rate. High foreign savings are indeed a driver of global footprint, and are a blockade against a satisfactory HPI performance. The new international division of labour is one of the prime drivers of high CO2 per capita emissions. Multinational Corporation (MNC penetration, the master variable of most quantitative dependency theories, blocks EPI and several other socially important processes. Worker remittances have a significant positive effect on the HPI, and HLYs. ConclusionWe re-analysed the solid macro-political and macro-sociological evidence on a global scale, published in the world’s leading peer-reviewed social science, ecological and public health journals, which seem to indicate that there are contradictions between unfettered globalization and unconstrained world economic openness and sustainable development and public health development. We suggest that there

  2. Imaging Hybrid Photon Detectors with a Reflective Photocathode

    CERN Document Server

    Ferenc, D

    2000-01-01

    Modern epitaxially grown photocathodes, like GaAsP, bring a very high inherent quantum efficiency, but are rather expensive due to the complicated manufacturing and mounting process. We argue that such photocathodes could be used in reflective mode, in order to avoid the risky and expensive removal of the epitaxial growth substrate. Besides that the quantum efficiency should increase considerably. In this paper we present results of the development of large imaging Hybrid Photon Detectors (HPDs), particularly designed for such reflective photocathodes.

  3. Quantum cloning

    Energy Technology Data Exchange (ETDEWEB)

    Buzek, Vladimir [Slovak Academy of Sciences (Slovakia); Hillery, Mark [City University of New York (United States)

    2001-11-01

    It is impossible to make perfect copies or 'clones' of unknown quantum states, but approximate copies could still have many uses in quantum computing. A computer is a physical device that consists of components that are all subject to the laws of physics. Since computers deal exclusively in information, there is a close connection between information and physical systems. But what happens if the components inside the computer become so small that they must be described by quantum mechanics rather than classical physics? The seemingly unstoppable decrease in the size of transistors and other components will force the computer industry to confront this question in the near future. However, a small band of far-sighted physicists has been thinking about these problems for almost two decades. Starting with the work of Paul Benioff, Richard Feynman, David Deutsch and Charles Bennett in the mid-1980s, the field of 'quantum information' has grown to become one of the most exciting areas of modern physics. These early pioneers realized that the representation of information by quantum systems, such as single electrons or photons, was an opportunity rather than a problem. (U.K.)

  4. Quantum walk computation

    International Nuclear Information System (INIS)

    Kendon, Viv

    2014-01-01

    Quantum versions of random walks have diverse applications that are motivating experimental implementations as well as theoretical studies. Recent results showing quantum walks are “universal for quantum computation” relate to algorithms, to be run on quantum computers. We consider whether an experimental implementation of a quantum walk could provide useful computation before we have a universal quantum computer

  5. PT-symmetry, indefinite metric, and nonlinear quantum mechanics

    Science.gov (United States)

    Brody, Dorje C.

    2017-12-01

    If a Hamiltonian of a quantum system is symmetric under space-time reflection, then the associated eigenvalues can be real. A conjugation operation for quantum states can then be defined in terms of space-time reflection, but the resulting Hilbert space inner product is not positive definite and gives rise to an interpretational difficulty. One way of resolving this difficulty is to introduce a superselection rule that excludes quantum states having negative norms. It is shown here that a quantum theory arising in this way gives an example of Kibble’s nonlinear quantum mechanics, with the property that the state space has a constant negative curvature. It then follows from the positive curvature theorem that the resulting quantum theory is not physically viable. This conclusion also has implications to other quantum theories obtained from the imposition of analogous superselection rules.

  6. Reconstruction of abstract quantum theory

    International Nuclear Information System (INIS)

    Drieschner, M.; Goernitz, T.; von Weizsaecker, C.F.

    1988-01-01

    Understanding quantum theory as a general theory of prediction, we reconstruct abstract quantum theory. Abstract means the general frame of quantum theory, without reference to a three-dimensional position space, to concepts like particle or field, or to special laws of dynamics. Reconstruction is the attempt to do this by formulating simple and plausible postulates on prediction in order to derive the basic concepts of quantum theory from them. Thereby no law of classical physics is presupposed which would then have to be quantized. We briefly discuss the relationship of theory and interpretation in physics and the fundamental role of time as a basic concept for physics. Then a number of assertions are given, formulated as succinctly as possible in order to make them easily quotable and comparable. The assertations are arranged in four groups: heuristic principles, verbal definitions of some terms, three basic postulates, and consequences. The three postulates of separable alternatives, indeterminism, and kinematics are the central points of this work. These brief assertions are commented upon, and their relationship with the interpretation of quantum theory is discussed. Also given are an outlook on the further development into concrete quantum theory and some philosophical reflections

  7. International Society for Quality of Life Research commentary on the draft European Medicines Agency reflection paper on the use of patient-reported outcome (PRO) measures in oncology studies.

    Science.gov (United States)

    Kyte, Derek; Reeve, Bryce B; Efficace, Fabio; Haywood, Kirstie; Mercieca-Bebber, Rebecca; King, Madeleine T; Norquist, Josephine M; Lenderking, William R; Snyder, Claire; Ring, Lena; Velikova, Galina; Calvert, Melanie

    2016-02-01

    In 2014, the European Medicines Agency (EMA) released for comment a draft reflection paper on the use of patient-reported outcome (PRO) measures in oncology studies. A twelve-member International Society for Quality of Life Research (ISOQOL) taskforce was convened to coordinate the ISOQOL response. Twenty-one ISOQOL members provided detailed comments and suggestions on the paper: 81 % from academia and 19 % from industry. Taskforce members consolidated and further refined these comments and shared the recommendations with the wider ISOQOL membership. A final response was submitted to the EMA in November 2014. The impending publication of the EMA reflection paper presents a valuable opportunity for ISOQOL to comment on the current direction of EMA PRO guidance and strategy. The EMA paper, although focused on cancer, could serve as a model for using PROs in other conditions, as it provides a useful update surrounding some of the design issues common to all trial research including PRO endpoints. However, we believe there are a number of additional areas in need of greater consideration. The purpose of this commentary is therefore to highlight the strengths of this timely and potentially useful document, but also to outline areas that may warrant further discussion.

  8. Quantum weirdness

    CERN Document Server

    Mullin, William J

    2017-01-01

    Quantum mechanics allows a remarkably accurate description of nature and powerful predictive capabilities. The analyses of quantum systems and their interpretation lead to many surprises, for example, the ability to detect the characteristics of an object without ever touching it in any way, via "interaction-free measurement," or the teleportation of an atomic state over large distances. The results can become downright bizarre. Quantum mechanics is a subtle subject that usually involves complicated mathematics -- calculus, partial differential equations, etc., for complete understanding. Most texts for general audiences avoid all mathematics. The result is that the reader misses almost all deep understanding of the subject, much of which can be probed with just high-school level algebra and trigonometry. Thus, readers with that level of mathematics can learn so much more about this fundamental science. The book starts with a discussion of the basic physics of waves (an appendix reviews some necessary class...

  9. Quantum waveguides

    CERN Document Server

    Exner, Pavel

    2015-01-01

    This monograph explains the theory of quantum waveguides, that is, dynamics of quantum particles confined to regions in the form of tubes, layers, networks, etc. The focus is on relations between the confinement geometry on the one hand and the spectral and scattering properties of the corresponding quantum Hamiltonians on the other. Perturbations of such operators, in particular, by external fields are also considered. The volume provides a unique summary of twenty five years of research activity in this area and indicates ways in which the theory can develop further. The book is fairly self-contained. While it requires some broader mathematical physics background, all the basic concepts are properly explained and proofs of most theorems are given in detail, so there is no need for additional sources. Without a parallel in the literature, the monograph by Exner and Kovarik guides the reader through this new and exciting field.

  10. Quantum gravity

    International Nuclear Information System (INIS)

    Isham, C.

    1989-01-01

    Gravitational effects are seen as arising from a curvature in spacetime. This must be reconciled with gravity's apparently passive role in quantum theory to achieve a satisfactory quantum theory of gravity. The development of grand unified theories has spurred the search, with forces being of equal strength at a unification energy of 10 15 - 10 18 GeV, with the ''Plank length'', Lp ≅ 10 -35 m. Fundamental principles of general relativity and quantum mechanics are outlined. Gravitons are shown to have spin-0, as mediators of gravitation force in the classical sense or spin-2 which are related to the quantisation of general relativity. Applying the ideas of supersymmetry to gravitation implies partners for the graviton, especially the massless spin 3/2 fermion called a gravitino. The concept of supersymmetric strings is introduced and discussed. (U.K.)

  11. Quantum mechanics

    CERN Document Server

    Ghosh, P K

    2014-01-01

    Quantum mechanics, designed for advanced undergraduate and graduate students of physics, mathematics and chemistry, provides a concise yet self-contained introduction to the formal framework of quantum mechanics, its application to physical problems and the interpretation of the theory. Starting with a review of some of the necessary mathematics, the basic concepts are carefully developed in the text. After building a general formalism, detailed treatment of the standard material - the harmonic oscillator, the hydrogen atom, angular momentum theory, symmetry transformations, approximation methods, identical particle and many-particle systems, and scattering theory - is presented. The concluding chapter discusses the interpretation of quantum mechanics. Some of the important topics discussed in the book are the rigged Hilbert space, deformation quantization, path integrals, coherent states, geometric phases, decoherene, etc. This book is characterized by clarity and coherence of presentation.

  12. Quantum deconvolution

    Science.gov (United States)

    Bény, Cédric

    2018-02-01

    We propose a method for stably removing noise from measurements of a quantum many-body system. The question is cast to a linear inverse problem by using a quantum Fischer information metric as figure of merit. This requires the ability to compute the adjoint of the noise channel with respect to the metric, which can be done analytically when the metric is evaluated at a Gaussian (quasi-free) state. This approach can be applied effectively to n-point functions of a quantum field theory. For translation invariant noise, this yields a stable deconvolution method on the first moments of the field which differs from what one would obtain from a purely classical analysis.

  13. Blind Quantum Signature with Blind Quantum Computation

    Science.gov (United States)

    Li, Wei; Shi, Ronghua; Guo, Ying

    2017-04-01

    Blind quantum computation allows a client without quantum abilities to interact with a quantum server to perform a unconditional secure computing protocol, while protecting client's privacy. Motivated by confidentiality of blind quantum computation, a blind quantum signature scheme is designed with laconic structure. Different from the traditional signature schemes, the signing and verifying operations are performed through measurement-based quantum computation. Inputs of blind quantum computation are securely controlled with multi-qubit entangled states. The unique signature of the transmitted message is generated by the signer without leaking information in imperfect channels. Whereas, the receiver can verify the validity of the signature using the quantum matching algorithm. The security is guaranteed by entanglement of quantum system for blind quantum computation. It provides a potential practical application for e-commerce in the cloud computing and first-generation quantum computation.

  14. Quantum control limited by quantum decoherence

    International Nuclear Information System (INIS)

    Xue, Fei; Sun, C. P.; Yu, S. X.

    2006-01-01

    We describe quantum controllability under the influences of the quantum decoherence induced by the quantum control itself. It is shown that, when the controller is considered as a quantum system, it will entangle with its controlled system and then cause quantum decoherence in the controlled system. In competition with this induced decoherence, the controllability will be limited by some uncertainty relation in a well-armed quantum control process. In association with the phase uncertainty and the standard quantum limit, a general model is studied to demonstrate the possibility of realizing a decoherence-free quantum control with a finite energy within a finite time. It is also shown that if the operations of quantum control are to be determined by the initial state of the controller, then due to the decoherence which results from the quantum control itself, there exists a low bound for quantum controllability

  15. Quantum machine learning for quantum anomaly detection

    Science.gov (United States)

    Liu, Nana; Rebentrost, Patrick

    2018-04-01

    Anomaly detection is used for identifying data that deviate from "normal" data patterns. Its usage on classical data finds diverse applications in many important areas such as finance, fraud detection, medical diagnoses, data cleaning, and surveillance. With the advent of quantum technologies, anomaly detection of quantum data, in the form of quantum states, may become an important component of quantum applications. Machine-learning algorithms are playing pivotal roles in anomaly detection using classical data. Two widely used algorithms are the kernel principal component analysis and the one-class support vector machine. We find corresponding quantum algorithms to detect anomalies in quantum states. We show that these two quantum algorithms can be performed using resources that are logarithmic in the dimensionality of quantum states. For pure quantum states, these resources can also be logarithmic in the number of quantum states used for training the machine-learning algorithm. This makes these algorithms potentially applicable to big quantum data applications.

  16. Quantum mechanics

    CERN Document Server

    Rae, Alastair I M

    2007-01-01

    PREFACESINTRODUCTION The Photoelectric Effect The Compton Effect Line Spectra and Atomic Structure De Broglie Waves Wave-Particle Duality The Rest of This Book THE ONE-DIMENSIONAL SCHRÖDINGER EQUATIONS The Time-Dependent Schrödinger Equation The Time-Independent Schrödinger Equation Boundary ConditionsThe Infinite Square Well The Finite Square Well Quantum Mechanical Tunneling The Harmonic Oscillator THE THREE-DIMENSIONAL SCHRÖDINGER EQUATIONS The Wave Equations Separation in Cartesian Coordinates Separation in Spherical Polar Coordinates The Hydrogenic Atom THE BASIC POSTULATES OF QUANTUM MEC

  17. Quantum mechanics

    CERN Document Server

    Zagoskin, Alexandre

    2015-01-01

    Written by Dr Alexandre Zagoskin, who is a Reader at Loughborough University, Quantum Mechanics: A Complete Introduction is designed to give you everything you need to succeed, all in one place. It covers the key areas that students are expected to be confident in, outlining the basics in clear jargon-free English, and then providing added-value features like summaries of key ideas, and even lists of questions you might be asked in your exam. The book uses a structure that is designed to make quantum physics as accessible as possible - by starting with its similarities to Newtonian physics, ra

  18. Lectures on Quantum Mechanics

    CERN Document Server

    Basdevant, Jean-Louis

    2007-01-01

    Beautifully illustrated and engagingly written, Lectures on Quantum Mechanics presents theoretical physics with a breathtaking array of examples and anecdotes. Basdevant's style is clear and stimulating, in the manner of a brisk classroom lecture that students can follow with ease and enjoyment. Here is a sample of the book's style, from the opening of Chapter 1: "If one were to ask a passer-by to quote a great formula of physics, chances are that the answer would be 'E = mc2'. Nevertheless, the formula 'E=hV' which was written in the same year 1905 by the same Albert Einstein, and which started quantum theory, concerns their daily life considerably more. In fact, of the three watershed years for physics toward the beginning of the 20th century - 1905: the Special Relativity of Einstein, Lorentz and Poincaré; 1915: the General Relativity of Einstein, with its extraordinary reflections on gravitation, space and time; and 1925: the full development of Quantum Mechanics - it is surely the last which has the mos...

  19. Quantum learning without quantum memory.

    Science.gov (United States)

    Sentís, G; Calsamiglia, J; Muñoz-Tapia, R; Bagan, E

    2012-01-01

    A quantum learning machine for binary classification of qubit states that does not require quantum memory is introduced and shown to perform with the minimum error rate allowed by quantum mechanics for any size of the training set. This result is shown to be robust under (an arbitrary amount of) noise and under (statistical) variations in the composition of the training set, provided it is large enough. This machine can be used an arbitrary number of times without retraining. Its required classical memory grows only logarithmically with the number of training qubits, while its excess risk decreases as the inverse of this number, and twice as fast as the excess risk of an "estimate-and-discriminate" machine, which estimates the states of the training qubits and classifies the data qubit with a discrimination protocol tailored to the obtained estimates.

  20. Quantum gravity and quantum cosmology

    CERN Document Server

    Papantonopoulos, Lefteris; Siopsis, George; Tsamis, Nikos

    2013-01-01

    Quantum gravity has developed into a fast-growing subject in physics and it is expected that probing the high-energy and high-curvature regimes of gravitating systems will shed some light on how to eventually achieve an ultraviolet complete quantum theory of gravity. Such a theory would provide the much needed information about fundamental problems of classical gravity, such as the initial big-bang singularity, the cosmological constant problem, Planck scale physics and the early-time inflationary evolution of our Universe.   While in the first part of this book concepts of quantum gravity are introduced and approached from different angles, the second part discusses these theories in connection with cosmological models and observations, thereby exploring which types of signatures of modern and mathematically rigorous frameworks can be detected by experiments. The third and final part briefly reviews the observational status of dark matter and dark energy, and introduces alternative cosmological models.   ...

  1. Quantum biological information theory

    CERN Document Server

    Djordjevic, Ivan B

    2016-01-01

    This book is a self-contained, tutorial-based introduction to quantum information theory and quantum biology. It serves as a single-source reference to the topic for researchers in bioengineering, communications engineering, electrical engineering, applied mathematics, biology, computer science, and physics. The book provides all the essential principles of the quantum biological information theory required to describe the quantum information transfer from DNA to proteins, the sources of genetic noise and genetic errors as well as their effects. Integrates quantum information and quantum biology concepts; Assumes only knowledge of basic concepts of vector algebra at undergraduate level; Provides a thorough introduction to basic concepts of quantum information processing, quantum information theory, and quantum biology; Includes in-depth discussion of the quantum biological channel modelling, quantum biological channel capacity calculation, quantum models of aging, quantum models of evolution, quantum models o...

  2. Quantum abacus

    Science.gov (United States)

    Cheon, Taksu; Tsutsui, Izumi; Fülöp, Tamás

    2004-09-01

    We show that the point interactions on a line can be utilized to provide U(2) family of qubit operations for quantum information processing. Qubits are realized as states localized in either side of the point interaction which represents a controllable gate. The qubit manipulation proceeds in a manner analogous to the operation of an abacus.

  3. Quantum chromodynamics

    International Nuclear Information System (INIS)

    Mosher, A.

    1980-01-01

    The symposium included lectures covering both the elements and the experimental tests of the theory of quantum chromdynamics. A three day topical conference was included which included the first results from PETRA as well as the latest reports from CERN, Fermilab, and SPEAR experiments. Twenty-one items from the symposium were prepared separately for the data base

  4. Quantum Theory

    NARCIS (Netherlands)

    Raedt, Hans De; Binder, K; Ciccotti, G

    1996-01-01

    The purpose of this set of lectures is to introduce the general concepts that are at the basis of the computer simulation algorithms that are used to study the behavior of condensed matter quantum systems. The emphasis is on the underlying concepts rather than on specific applications. Topics

  5. Quantum Biology

    Directory of Open Access Journals (Sweden)

    Alessandro Sergi

    2009-06-01

    Full Text Available A critical assessment of the recent developmentsof molecular biology is presented.The thesis that they do not lead to a conceptualunderstanding of life and biological systems is defended.Maturana and Varela's concept of autopoiesis is briefly sketchedand its logical circularity avoided by postulatingthe existence of underlying living processes,entailing amplification from the microscopic to the macroscopic scale,with increasing complexity in the passage from one scale to the other.Following such a line of thought, the currently accepted model of condensed matter, which is based on electrostatics and short-ranged forces,is criticized. It is suggested that the correct interpretationof quantum dispersion forces (van der Waals, hydrogen bonding, and so onas quantum coherence effects hints at the necessity of includinglong-ranged forces (or mechanisms for them incondensed matter theories of biological processes.Some quantum effects in biology are reviewedand quantum mechanics is acknowledged as conceptually important to biology since withoutit most (if not all of the biological structuresand signalling processes would not even exist. Moreover, it is suggested that long-rangequantum coherent dynamics, including electron polarization,may be invoked to explain signal amplificationprocess in biological systems in general.

  6. Quantum Interferometry

    Science.gov (United States)

    Dowling, Jonathan P.

    2000-01-01

    Recently, several researchers, including yours truly, have been able to demonstrate theoretically that quantum photon entanglement has the potential to also revolutionize the entire field of optical interferometry, by providing many orders of magnitude improvement in interferometer sensitivity. The quantum entangled photon interferometer approach is very general and applies to many types of interferometers. In particular, without nonlocal entanglement, a generic classical interferometer has a statistical-sampling shot-noise limited sensitivity that scales like 1/Sqrt[N], where N is the number of particles (photons, electrons, atoms, neutrons) passing through the interferometer per unit time. However, if carefully prepared quantum correlations are engineered between the particles, then the interferometer sensitivity improves by a factor of Sqrt[N] (square root of N) to scale like 1/N, which is the limit imposed by the Heisenberg Uncertainty Principle. For optical (laser) interferometers operating at milliwatts of optical power, this quantum sensitivity boost corresponds to an eight-order-of-magnitude improvement of signal to noise. Applications are to tests of General Relativity such as ground and orbiting optical interferometers for gravity wave detection, Laser Interferometer Gravity Observatory (LIGO) and the European Laser Interferometer Space Antenna (LISA), respectively.

  7. Quantum logic

    International Nuclear Information System (INIS)

    Mittelstaedt, P.

    1979-01-01

    The subspaces of Hilbert space constitute an orthocomplemented quasimodular lattice Lsub(q) for which neither a two-valued function nor generalized truth function exist. A generalisation of the dialogic method can be used as an interpretation of a lattice Lsub(qi), which may be considered as the intuitionistic part of Lsub(q). Some obvious modifications of the dialogic method are introduced which come from the possible incommensurability of propositions about quantum mechanical systems. With the aid of this generalized dialogic method a propositional calculus Qsub(eff) is derived which is similar to the calculus of effective (intuitionistic) logic, but contains a few restrictions which are based on the incommensurability of quantum mechanical propositions. It can be shown within the framework of the calculus Qsub(eff) that the value-definiteness of the elementary propositions which are proved by quantum mechanical propositions is inherited by all finite compund propositions. In this way one arrives at the calculus Q of full quantum logic which incorporates the principle of excluded middle for all propositions and which is a model for the lattice Lsub(q). (Auth.)

  8. Quantum chaos

    International Nuclear Information System (INIS)

    Seligman, T.H.

    1984-01-01

    Some general points of view on the implication of chaotic behaviour of a classical Hamiltonian system for the corresponding quantum system are discussed. The relevance of spectral statistics emerges. Various results on this subject are reported that tend to support these considerations. Limitations of this point of view are discussed with particular attention to the question of localization

  9. Quantum Metaphotonics

    Science.gov (United States)

    2016-03-24

    FTIR ) spectroscopy. Quantum Well-Antenna Coupled System From our previous grant, and in collaboration with the group of Prof. Martin Wegener, we...Fan, A. P. Vasudev, J. S. White, Z. Yu, W. Cai, J. A. Schuller, S. Fan, and M. L. Brongersma, “Semiconductor nanowire optical antenna solar absorbers

  10. Quantum Computation

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 16; Issue 9. Quantum Computation - Particle and Wave Aspects of Algorithms. Apoorva Patel. General Article Volume 16 Issue 9 September 2011 pp 821-835. Fulltext. Click here to view fulltext PDF. Permanent link:

  11. Quantum Computing

    Indian Academy of Sciences (India)

    To start the quantum algorithm we prepare a super- position of numbers from 0 to M - 1 using the Walsh-. Hadamard transformation on ... Hence, we create a state in which the ampli- tudes have the same period as f. This we do by measur- .... IT Business Incubator. Department of Physics. liT Powai,. Mumbai 400 076, India.

  12. Macroscopic quantum systems and gravitational phenomena

    International Nuclear Information System (INIS)

    Pikovski, I.

    2014-01-01

    Low-energy quantum systems are studied theoretically in light of possible experiments to test the interplay between quantum theory and general relativity. The research focus in this thesis is on quantum systems which can be controlled with very high precision and which allow for tests of quantum theory at novel scales in terms of mass and size. The pulsed regime of opto-mechanics is explored and it is shown how short optical pulses can be used to prepare and characterize quantum states of a massive mechanical resonator, and how some phenomenological models of quantum gravity can be probed. In addition, quantum interferometry with photons and matter-waves in the presence of gravitational time dilation is considered. It is shown that time dilation causes entanglement between internal states and the center-of-mass position and that it leads to decoherence of all composite quantum systems. The results of the thesis show that the interplay between quantum theory and general relativity affects even low-energy quantum systems and that it offers novel phenomena which can be probed in experiments. (author) [de

  13. «Land of Confusion»: Quantum Physic In IR Theory?

    Directory of Open Access Journals (Sweden)

    Tatiana A. Alekseeva

    2016-01-01

    Full Text Available The article deals with the "Quantum mind"hypothesis which has been elaborated in recent works of Alexander Wendt. It is ultimately significant to analyze this hypothesis and to expand on its difficulties and possible inconsistencies given Wendt's credentials in IR theorizing. It allows us to develop a new approach and promising research program on the basis of the hypothesis and its critical reflection. Wendt's quantum physicalism (or holism implies serious philosophical injury and outstanding usage of different science disciplines' apparatus including physics, biology, and psychology. Thought-provoking approach of Wendt boosts researching efforts within the field of political philosophy, world politics and international relations. The main feature of the hypothesis is the idea of quantum nature in social and political processes which appears to be the consequence of epistemological authority of current science. Alexander Wendt proposes several explanations for quantum foundations within the political and social processes including wide-known "agent-structure" dilemma. According to him, invisibility of social structures does not lead to denial of its existence. Firstly, social structures emerge from the space of possibilities and are not directly dependant on material factors. Secondly, invisibility and its acceptance in different areas are parts of science clarification in many areas including quantum physics. The article discuses how quantum physics principles such as particle-wave dualism, superposition and size absoluteness can be useful in social and political studies. This allows us to demonstrate the given hypothesi' potential in research field of social sciences with regard to international relations and world politics.

  14. Quantum cryptography beyond quantum key distribution

    NARCIS (Netherlands)

    A. Broadbent (Anne); C. Schaffner (Christian)

    2016-01-01

    textabstractQuantum cryptography is the art and science of exploiting quantum mechanical effects in order to perform cryptographic tasks. While the most well-known example of this discipline is quantum key distribution (QKD), there exist many other applications such as quantum money, randomness

  15. Quantum cryptography beyond quantum key distribution

    NARCIS (Netherlands)

    Broadbent, A.; Schaffner, C.

    2016-01-01

    Quantum cryptography is the art and science of exploiting quantum mechanical effects in order to perform cryptographic tasks. While the most well-known example of this discipline is quantum key distribution (QKD), there exist many other applications such as quantum money, randomness generation,

  16. Quantum Statistical Mechanics on a Quantum Computer

    NARCIS (Netherlands)

    Raedt, H. De; Hams, A.H.; Michielsen, K.; Miyashita, S.; Saito, K.; Saito, E.

    2000-01-01

    We describe a simulation method for a quantum spin model of a generic, general purpose quantum computer. The use of this quantum computer simulator is illustrated through several implementations of Grover’s database search algorithm. Some preliminary results on the stability of quantum algorithms

  17. Slip in quantum fluids

    International Nuclear Information System (INIS)

    Einzel, D.; Parpia, J.M.

    1997-01-01

    In this review the authors describe theoretical and experimental investigations of general slip phenomena in context with the flow of the quantum liquids 3 He, 4 He and their mixtures at low temperatures. The phenomena of slip is related to a boundary effect. It occurs when sufficiently dilute gases flow along the wall of an experimental cell. A fluid is said to exhibit slip when the fluid velocity at the wall is not equal to the wall's velocity. Such a situation occurs whenever the wall reflects the fluid particles in a specular-like manner, and/or if the fluid is describable in terms of a dilute ordinary gas (classical fluid) or a dilute gas of thermal excitations (quantum fluid). The slip effect in quantum fluids is discussed theoretically on the basis of generalized Landau-Boltzmann transport equations and generalized to apply to a regime of ballistic motion of the quasiparticles in the fluid. The central result is that the transport coefficient of bulk shear viscosity, which typically enters in the Poiseuille flow resistance and the transverse acoustic impedance, has to be replaced by geometry dependent effective viscosity, which depends on the details of the interaction of the fluid particles with the cell walls. The theoretical results are compared with various experimental data obtained in different geometries and for both Bose and Fermi quantum fluids. Good agreement between experiment and theory is found particularly in the case of pure normal and superfluid 3 He, with discrepancies probably arising because of deficiencies in characterization of the experimental surfaces

  18. Quantum Gravity

    International Nuclear Information System (INIS)

    Giribet, G E

    2005-01-01

    Claus Kiefer presents his book, Quantum Gravity, with his hope that '[the] book will convince readers of [the] outstanding problem [of unification and quantum gravity] and encourage them to work on its solution'. With this aim, the author presents a clear exposition of the fundamental concepts of gravity and the steps towards the understanding of its quantum aspects. The main part of the text is dedicated to the analysis of standard topics in the formulation of general relativity. An analysis of the Hamiltonian formulation of general relativity and the canonical quantization of gravity is performed in detail. Chapters four, five and eight provide a pedagogical introduction to the basic concepts of gravitational physics. In particular, aspects such as the quantization of constrained systems, the role played by the quadratic constraint, the ADM decomposition, the Wheeler-de Witt equation and the problem of time are treated in an expert and concise way. Moreover, other specific topics, such as the minisuperspace approach and the feasibility of defining extrinsic times for certain models, are discussed as well. The ninth chapter of the book is dedicated to the quantum gravitational aspects of string theory. Here, a minimalistic but clear introduction to string theory is presented, and this is actually done with emphasis on gravity. It is worth mentioning that no hard (nor explicit) computations are presented, even though the exposition covers the main features of the topic. For instance, black hole statistical physics (within the framework of string theory) is developed in a pedagogical and concise way by means of heuristical arguments. As the author asserts in the epilogue, the hope of the book is to give 'some impressions from progress' made in the study of quantum gravity since its beginning, i.e., since the end of 1920s. In my opinion, Kiefer's book does actually achieve this goal and gives an extensive review of the subject. (book review)

  19. Emergence of quantum mechanics from classical statistics

    International Nuclear Information System (INIS)

    Wetterich, C

    2009-01-01

    The conceptual setting of quantum mechanics is subject to an ongoing debate from its beginnings until now. The consequences of the apparent differences between quantum statistics and classical statistics range from the philosophical interpretations to practical issues as quantum computing. In this note we demonstrate how quantum mechanics can emerge from classical statistical systems. We discuss conditions and circumstances for this to happen. Quantum systems describe isolated subsystems of classical statistical systems with infinitely many states. While infinitely many classical observables 'measure' properties of the subsystem and its environment, the state of the subsystem can be characterized by the expectation values of only a few probabilistic observables. They define a density matrix, and all the usual laws of quantum mechanics follow. No concepts beyond classical statistics are needed for quantum physics - the differences are only apparent and result from the particularities of those classical statistical systems which admit a quantum mechanical description. In particular, we show how the non-commuting properties of quantum operators are associated to the use of conditional probabilities within the classical system, and how a unitary time evolution reflects the isolation of the subsystem.

  20. Quantum optics with single quantum dot devices

    International Nuclear Information System (INIS)

    Zwiller, Valery; Aichele, Thomas; Benson, Oliver

    2004-01-01

    A single radiative transition in a single-quantum emitter results in the emission of a single photon. Single quantum dots are single-quantum emitters with all the requirements to generate single photons at visible and near-infrared wavelengths. It is also possible to generate more than single photons with single quantum dots. In this paper we show that single quantum dots can be used to generate non-classical states of light, from single photons to photon triplets. Advanced solid state structures can be fabricated with single quantum dots as their active region. We also show results obtained on devices based on single quantum dots

  1. Quantum mechanics a paradigms approach

    CERN Document Server

    McIntyre, David H; Tate, Janet

    2012-01-01

    This innovative new text presents quantum mechanics in a manner that directly reflects the methods used in modern physics research—making the material more approachable and preparing students more thoroughly for real research. Most texts in this area start with a bit of history and then move directly to wave-particle problems with accompanying heavy mathematical analysis; Quantum Mechanics provides a foundation in experimental phenomena and uses a more approachable, less intimidating, more powerful mathematical matrix model. Beginning with the Stern-Gerlach experiments and the discussion of spin measurements, and using bra-ket notation, the authors introduce an important notational system that is used throughout quantum mechanics. This non-traditional presentation is designed to enhance students’ understanding and strengthen their intuitive grasp of the subject.

  2. Sterically Shielded Electron Transporting Material with Nearly 100% Internal Quantum Efficiency and Long Lifetime for Thermally Activated Delayed Fluorescent and Phosphorescent OLEDs.

    Science.gov (United States)

    Zhang, Dongdong; Wei, Pengcheng; Zhang, Deqiang; Duan, Lian

    2017-06-07

    A high triplet energy (T 1 ) is usually taken as the prerequisite of the good exciton confinement of electron transporting materials (ETMs); however, there is usually a tradeoff with large mobility and stability. Here, we demonstrated that good exciton confinement can also be realized utilizing a low-T 1 ETM with a sterically shielding low-T 1 unit. Given the short-range interaction of the Dexter energy transfer, the large steric side groups of the low-T 1 ETM can effectively hinder the T 1 of the emitters from being quenched by increasing the intermolecular distance. Based on this concept, a maximum external quantum efficiency (EQE max ) as high as 21.3% was observed in the sky-blue thermally activated delayed fluorescence device using a low-T 1 ETM, with the EQE remaining at 21.2% at 1000 cd/m 2 and 17.8% at 5000 cd/m 2 . Further, an EQE max as high as 25.5%, a low turn-on voltage of 2.3 V, as well as a long T 90 of over 400 h at an initial luminance of 5000 cd/m 2 were achieved for green phosphorescent devices. This work highlights a viable strategy for developing high-performance ETMs, paving their way toward practical applications.

  3. Single Quantum Dot Tracking Reveals that an Individual Multivalent HIV-1 Tat Protein Transduction Domain Can Activate Machinery for Lateral Transport and Endocytosis

    OpenAIRE

    Suzuki, Yasuhiro; Roy, Chandra Nath; Promjunyakul, Warunya; Hatakeyama, Hiroyasu; Gonda, Kohsuke; Imamura, Junji; Vasudevanpillai, Biju; Ohuchi, Noriaki; Kanzaki, Makoto; Higuchi, Hideo; Kaku, Mitsuo

    2013-01-01

    The mechanisms underlying the cellular entry of the HIV-1 Tat protein transduction domain (TatP) and the molecular information necessary to improve the transduction efficiency of TatP remain unclear due to the technical limitations for direct visualization of TatP's behavior in cells. Using confocal microscopy, total internal reflection fluorescence microscopy, and four-dimensional microscopy, we developed a single-molecule tracking assay for TatP labeled with quantum dots (QDs) to examine th...

  4. Efficient quantum walk on a quantum processor.

    Science.gov (United States)

    Qiang, Xiaogang; Loke, Thomas; Montanaro, Ashley; Aungskunsiri, Kanin; Zhou, Xiaoqi; O'Brien, Jeremy L; Wang, Jingbo B; Matthews, Jonathan C F

    2016-05-05

    The random walk formalism is used across a wide range of applications, from modelling share prices to predicting population genetics. Likewise, quantum walks have shown much potential as a framework for developing new quantum algorithms. Here we present explicit efficient quantum circuits for implementing continuous-time quantum walks on the circulant class of graphs. These circuits allow us to sample from the output probability distributions of quantum walks on circulant graphs efficiently. We also show that solving the same sampling problem for arbitrary circulant quantum circuits is intractable for a classical computer, assuming conjectures from computational complexity theory. This is a new link between continuous-time quantum walks and computational complexity theory and it indicates a family of tasks that could ultimately demonstrate quantum supremacy over classical computers. As a proof of principle, we experimentally implement the proposed quantum circuit on an example circulant graph using a two-qubit photonics quantum processor.

  5. Quantum channel construction with circuit quantum electrodynamics

    Science.gov (United States)

    Shen, Chao; Noh, Kyungjoo; Albert, Victor V.; Krastanov, Stefan; Devoret, M. H.; Schoelkopf, R. J.; Girvin, S. M.; Jiang, Liang

    2017-04-01

    Quantum channels can describe all transformations allowed by quantum mechanics. We adapt two existing works [S. Lloyd and L. Viola, Phys. Rev. A 65, 010101 (2001), 10.1103/PhysRevA.65.010101 and E. Andersson and D. K. L. Oi, Phys. Rev. A 77, 052104 (2008), 10.1103/PhysRevA.77.052104] to superconducting circuits, featuring a single qubit ancilla with quantum nondemolition readout and adaptive control. This construction is efficient in both ancilla dimension and circuit depth. We point out various applications of quantum channel construction, including system stabilization and quantum error correction, Markovian and exotic channel simulation, implementation of generalized quantum measurements, and more general quantum instruments. Efficient construction of arbitrary quantum channels opens up exciting new possibilities for quantum control, quantum sensing, and information processing tasks.

  6. Quantum Secure Dialogue with Quantum Encryption

    International Nuclear Information System (INIS)

    Ye Tian-Yu

    2014-01-01

    How to solve the information leakage problem has become the research focus of quantum dialogue. In this paper, in order to overcome the information leakage problem in quantum dialogue, a novel approach for sharing the initial quantum state privately between communicators, i.e., quantum encryption sharing, is proposed by utilizing the idea of quantum encryption. The proposed protocol uses EPR pairs as the private quantum key to encrypt and decrypt the traveling photons, which can be repeatedly used after rotation. Due to quantum encryption sharing, the public announcement on the state of the initial quantum state is omitted, thus the information leakage problem is overcome. The information-theoretical efficiency of the proposed protocol is nearly 100%, much higher than previous information leakage resistant quantum dialogue protocols. Moreover, the proposed protocol only needs single-photon measurements and nearly uses single photons as quantum resource so that it is convenient to implement in practice. (general)

  7. Efficient quantum walk on a quantum processor

    Science.gov (United States)

    Qiang, Xiaogang; Loke, Thomas; Montanaro, Ashley; Aungskunsiri, Kanin; Zhou, Xiaoqi; O'Brien, Jeremy L.; Wang, Jingbo B.; Matthews, Jonathan C. F.

    2016-01-01

    The random walk formalism is used across a wide range of applications, from modelling share prices to predicting population genetics. Likewise, quantum walks have shown much potential as a framework for developing new quantum algorithms. Here we present explicit efficient quantum circuits for implementing continuous-time quantum walks on the circulant class of graphs. These circuits allow us to sample from the output probability distributions of quantum walks on circulant graphs efficiently. We also show that solving the same sampling problem for arbitrary circulant quantum circuits is intractable for a classical computer, assuming conjectures from computational complexity theory. This is a new link between continuous-time quantum walks and computational complexity theory and it indicates a family of tasks that could ultimately demonstrate quantum supremacy over classical computers. As a proof of principle, we experimentally implement the proposed quantum circuit on an example circulant graph using a two-qubit photonics quantum processor. PMID:27146471

  8. A Reflective Look at Reflecting Teams

    Science.gov (United States)

    Pender, Rebecca L.; Stinchfield, Tracy

    2012-01-01

    This article reviewed existing literature and research on the reflecting team process. There is a dearth of empirical research that explores the reflecting team process and the outcome of counseling that uses reflecting teams. Implications of using reflecting teams for counselors, counselor educators, and clients will be discussed. A call for…

  9. Quantum computation by measurement and quantum memory

    International Nuclear Information System (INIS)

    Nielsen, Michael A.

    2003-01-01

    What resources are universal for quantum computation? In the standard model of a quantum computer, a computation consists of a sequence of unitary gates acting coherently on the qubits making up the computer. This requirement for coherent unitary dynamical operations is widely believed to be the critical element of quantum computation. Here we show that a very different model involving only projective measurements and quantum memory is also universal for quantum computation. In particular, no coherent unitary dynamics are involved in the computation

  10. Uncertainty and complementarity in axiomatic quantum mechanics

    International Nuclear Information System (INIS)

    Lahti, P.J.

    1980-01-01

    An investigation of the uncertainty principle and the complementarity principle is carried through. The physical content of these principles and their representation in the conventional Hilbert space formulation of quantum mechanics forms a natural starting point. Thereafter is presented more general axiomatic framework for quantum mechanics, namely, a probability function formulation of the theory. Two extra axioms are stated, reflecting the ideas of the uncertainty principle and the complementarity principle, respectively. The quantal features of these axioms are explicated. (author)

  11. Experimental status of quaternionic quantum mechanics

    International Nuclear Information System (INIS)

    Brumby, S.P.; Joshi, G.C.

    1995-01-01

    Analysis of the logical foundations of quantum mechanics indicates the possibility of constructing a theory using quaternionic Hilbert spaces. Whether this mathematical structure reflects reality is a matter for experiment to decide. The only direct search for quaternionic quantum mechanics yet carried out is reviewed and is proposed to look for quaternionic effects in correlated multi-particle systems. It is also discussed how such experiments might distinguish between the several quaternionic models proposed in the literature. 21 refs

  12. Quantum groups and quantum spaces

    Energy Technology Data Exchange (ETDEWEB)

    Wess, Julius [Max-Planck Institut fuer Physik, Werner-Heisenberg Institut, Muenchen (Germany)]|[Muenchen Univ. (Germany). Sektion Physik

    1996-07-01

    The lecture presents quantum groups and spaces, conjugation and SL{sub q}(2,C), q-Euclidean and q-Minkowski spaces. The concept of the quantum group SL{sub q}(2,C) prior developed is generalized to allow a conjugation, which is essential for physics. We have seen that quantum groups lead in a natural way to non-commutative spaces, a concept we feel should be exploited for physics, These non-commutative spaces have a well-defined mathematical structure, inherited from quantum group symmetries. As a first example, we have seen the q-deformed spinor space, the Manin plane. Spinors are the space of the fundamental representation of SU(2), and all other finite dimensional representations can be obtained by products of this representation. Spinors and their conjugates play the same role for S L(2,C). In this lecture we shall start from the Manin plane and discuss q-bi spinors, objects that span the q-Euclidean space for SU{sub q}(2) or the q-Minkowski space for SL{sub q}(2,C)

  13. Signatures of bifurcation on quantum correlations: Case of the quantum kicked top.

    Science.gov (United States)

    Bhosale, Udaysinh T; Santhanam, M S

    2017-01-01

    Quantum correlations reflect the quantumness of a system and are useful resources for quantum information and computational processes. Measures of quantum correlations do not have a classical analog and yet are influenced by classical dynamics. In this work, by modeling the quantum kicked top as a multiqubit system, the effect of classical bifurcations on measures of quantum correlations such as the quantum discord, geometric discord, and Meyer and Wallach Q measure is studied. The quantum correlation measures change rapidly in the vicinity of a classical bifurcation point. If the classical system is largely chaotic, time averages of the correlation measures are in good agreement with the values obtained by considering the appropriate random matrix ensembles. The quantum correlations scale with the total spin of the system, representing its semiclassical limit. In the vicinity of trivial fixed points of the kicked top, the scaling function decays as a power law. In the chaotic limit, for large total spin, quantum correlations saturate to a constant, which we obtain analytically, based on random matrix theory, for the Q measure. We also suggest that it can have experimental consequences.

  14. Flower-Like Internal Emission Distribution of LEDs with Monolithic Integration of InGaN-based Quantum Wells Emitting Narrow Blue, Green, and Red Spectra.

    Science.gov (United States)

    Lee, Kwanjae; Choi, Ilgyu; Lee, Cheul-Ro; Chung, Tae-Hoon; Kim, Yoon Seok; Jeong, Kwang-Un; Chung, Dong Chul; Kim, Jin Soo

    2017-08-02

    We report a phosphor-free white light-emitting diodes (LED) realized by the monolithic integration of In 0.18 Ga 0.82 N/GaN (438 nm, blue), In 0.26 Ga 0.74 N/GaN (513 nm, green), and In 0.45 Ga 0.55 N/In 0.13 Ga 0.87 N (602 nm, red) quantum wells (QWs) as an active medium. The QWs corresponding to blue and green light were grown using a conventional growth mode. For the red spectral emission, five-stacked In 0.45 Ga 0.55 N/In 0.13 Ga 0.87 N QWs were realized by the so-called Ga-flow-interruption (Ga-FI) technique, wherein the Ga supply was periodically interrupted during the deposition of In 0.3 Ga 0.7 N to form an In 0.45 Ga 0.55 N well. The vertical and lateral distributions of the three different light emissions were investigated by fluorescence microscope (FM) images. The FM image measured at a focal point in the middle of the n-GaN cladding layer for the red-emitting LED shows that light emissions with flower-like patterns with six petals are periodically observed. The chromaticity coordinates of the electroluminescence spectrum for the white LEDs at an injection current of 80 mA are measured to be (0.316, 0.312), which is close to ideal white light. In contrast with phosphor-free white-light-emitting devices based on nanostructures, our white light device exhibits a mixture of three independent wavelengths by monolithically grown InGaN-based QWs, thus demonstrating a more facile technique to obtain white LEDs.

  15. International Cooperation Programs Of The Department Of Nuclear And Quantum Engineering (NQe) At KAIST For Nuclear Program Developing Countries In Asia

    International Nuclear Information System (INIS)

    Poong Huyn Seong; Ki SoonYum

    2008-01-01

    NQe of KAIST has developed and conducted a few international cooperation programs for Asian countries which are actively developing their nuclear programs. These include inviting several students from these countries annually for short term period such as one semester and have them experience nuclear education programs at KAIST by taking NQe courses, attending Korean Nuclear Society (KNS) meeting, and visiting some nuclear related organizations such as nuclear power plants and Doosan Heavy Industry Machine shops in Korea. These also include visiting lectures conducted by KAIST NQe professors at some universities in the nuclear program developing countries. Both of above two programs have been performed mainly for Vietnam so far but now are becoming expanded. The last program of these international cooperation activities at NQe for Nuclear Program Developing countries in Asia is the RCA/KAIST master degree program which is open to all 17 RCA countries. Thus far, we have had about 18 students from 9 different countries. NQe is looking for some more international cooperation programs which are beneficial both for Korea and for other countries right now. NQe is starting a joint summer school program between KAIST and Shanghai Jiatong University in this sense. Also, some kind of cooperation between NQe at KAIST and Department of Engineering Physics at Tsinghua University in China is also being sought now. (author)

  16. Physics of quantum computation

    International Nuclear Information System (INIS)

    Belokurov, V.V.; Khrustalev, O.A.; Sadovnichij, V.A.; Timofeevskaya, O.D.

    2003-01-01

    In the paper, the modern status of the theory of quantum computation is considered. The fundamental principles of quantum computers and their basic notions such as quantum processors and computational basis states of the quantum Turing machine as well as the quantum Fourier transform are discussed. Some possible experimental realizations on the basis of NMR methods are given

  17. Spin network quantum simulator

    OpenAIRE

    Marzuoli, Annalisa; Rasetti, Mario

    2002-01-01

    We propose a general setting for a universal representation of the quantum structure on which quantum information stands, whose dynamical evolution (information manipulation) is based on angular momentum recoupling theory. Such scheme complies with the notion of 'quantum simulator' in the sense of Feynmann, and is shown to be related with the topological quantum field theory approach to quantum computation.

  18. Quantum Information Science

    Science.gov (United States)

    2012-02-01

    create simple single photon quantum optical gates. In the standard quantum circuit model ( QCM ) paradigm, quantum computations are executed by...substantially reduce the resource overhead in the standard QCM to photon-based quantum computation. Experimental: Photons are particularly desirable...sequence of reversible unitary gates in the usual quantum circuit model ( QCM ). The initial entanglement resources of the OWQC are called graph

  19. Quantum Cosmology

    Science.gov (United States)

    Bojowald, Martin

    The universe, ultimately, is to be described by quantum theory. Quantum aspects of all there is, including space and time, may not be significant for many purposes, but are crucial for some. And so a quantum description of cosmology is required for a complete and consistent worldview. At any rate, even if we were not directly interested in regimes where quantum cosmology plays a role, a complete physical description could not stop at a stage before the whole universe is reached. Quantum theory is essential in the microphysics of particles, atoms, molecules, solids, white dwarfs and neutron stars. Why should one expect this ladder of scales to end at a certain size? If regimes are sufficiently violent and energetic, quantum effects are non-negligible even on scales of the whole cosmos; this is realized at least once in the history of the universe: at the big bang where the classical theory of general relativity would make energy densities diverge. 1.Lachieze-Rey, M., Luminet, J.P.: Phys. Rept. 254,135 (1995), gr-qc/9605010 2.BSDeWitt1967Phys. Rev.160511131967PhRv..160.1113D0158.4650410.1103/PhysRev.160.1113DeWitt, B.S.: Phys. Rev. 160(5), 1113 (1967) 3.Wiltshire, D.L.: In: Robson B., Visvanathan N., Woolcock W.S. (eds.) Cosmology: The Physics of the Universe, pp. 473-531. World Scientific, Singapore (1996). gr-qc/0101003 4.Isham C.J.: In: DeWitt, B.S., Stora, R. (eds.) Relativity, Groups and Topology II. Lectures Given at the 1983 Les Houches Summer School on Relativity, Groups and Topology, Elsevier Science Publishing Company (1986) 5.Klauder, J.: Int. J. Mod. Phys. D 12, 1769 (2003), gr-qc/0305067 6.Klauder, J.: Int. J. Geom. Meth. Mod. Phys. 3, 81 (2006), gr-qc/0507113 7.DGiulini1995Phys. Rev. D5110563013381161995PhRvD..51.5630G10.1103/PhysRevD.51.5630Giulini, D.: Phys. Rev. D 51(10), 5630 (1995) 8.Kiefer, C., Zeh, H.D.: Phys. Rev. D 51, 4145 (1995), gr-qc/9402036 9.WFBlythCJIsham1975Phys. Rev. D117684086991975PhRvD..11..768B10.1103/PhysRevD.11.768Blyth, W

  20. Metrology of electrical quantum

    International Nuclear Information System (INIS)

    Camon, A.

    1996-01-01

    Since 1989 the electrical metrology laboratory of TPYCEA and the low temperature physics department of ICMA have been collaborating in the development of electrical quantum metrology. ICMA has been mainly dedicated to implement the state of the art quantum standards for which its experience on cryogenics, superconductivity and low noise instrumentation was essential. On the other hand TPYCEA concentrated its efforts on the metrological aspects, in which it has great experience. The complimentary knowledge of both laboratories, as well as the advice obtained from several prestigious metrology institutes was the key to successful completion of the two projects so far developed: i) The Josephson voltage standard (1989-1991) ii) The quantum Hall resistance standard (1991-1996) This report contains a description of both projects. Even though we can consider that the two projects are finished from the instrumental and metrological point of view, there is still a strong cooperation between ICMA and TPYCEA on the improvement of these standards, as well as on their international validation

  1. Quantum psyche

    CERN Document Server

    Baaquie, Belal E; Demongeot, J; Galli-Carminati, Giuliana; Martin, F; Teodorani, Massimo

    2015-01-01

    At the end of the 19th century Sigmund Freud discovered that our acts and choices are not only decisions of our consciousness, but that they are also deeply determined by our unconscious (the so-called "Freudian unconscious"). During a long correspondence between them (1932-1958) Wolfgang Pauli and Carl Gustav Jung speculated that the unconscious could be a quantum system. This book is addressed both to all those interested in the new developments of the age-old enquiry in the relations between mind and matter, and also to the experts in quantum physics that are interested in a formalisation of this new approach. The description of the "Bilbao experiment" adds a very interesting experimental inquiry into the synchronicity effect in a group situation, linking theory to a quantifiable verification of these subtle effects. Cover design: "Entangled Minds". Riccardo Carminati Galli, 2014.

  2. Quantum quandaries

    CERN Document Server

    Weber, Timothy

    1995-01-01

    For extra credit or just for the fun of it-why not try a brainteaser? This collection brings together the first 100 brainteasers from Quantum magazine, published by the National Science Teachers Association in collaboration with the Russian magazine Kvant. Through its pages, you'll find number rebuses, geometry ticklers, logic puzzles, and quirky questions with a physics twist. Students and teachers alike will enjoy these fun quandaries.

  3. Quantum hadrodynamics

    International Nuclear Information System (INIS)

    Serot, B.D.

    1992-01-01

    It is therefore essential to develop reliable nuclear models that go beyond the traditional non-relativistic many-body framework. The arguments for renormalizable models based on hadronic degrees of freedom (quantum hadrodynamics) are presented, and the assumptions underlying this framework are discussed. The Walecka model, which contains neutrons, protons, and neutral scalar and vector mesons, is considered first as a simple example. The development is based on the relativistic mean-field and Hartree approximations, and their application to infinite matter and atomic nuclei. Some successes of this model are discussed, such as the nuclear equation of state, the derivation of the shell model, the prediction of nuclear properties throughout the periodic table, and the inclusion of zero-point vacuum corrections. The important concepts of Lorentz covariance and self-consistency are emphasized and the new dynamical features that arise in a relativistic many-body framework are highlighted. The computation of isoscalar magnetic moments is presented as an illustrative example. Calculations beyond the relativistic mean-field and Hartree approximations (for example, Dirac-Hartree-Fock and Dirac-Brueckner) are considered next, as well as recent efforts to incorporate the full role of the quantum vacuum in a consistent fashion. An extended model containing isovector pi and rho mesons is then developed; the dynamics is based on the chirally invariant linear sigma model. The difficulties in constructing realistic chiral descriptions of nuclear matter and nuclei are analysed, and the connection between the sigma model and the Walecka model is established. Finally, the relationship between quantum hadrodynamics and quantum chromodynamics is briefly addressed. (Author)

  4. Quantum profiles

    National Research Council Canada - National Science Library

    Bernstein, Jeremy

    1991-01-01

    ... excitement- that goes on in the advanced fields of physics.'' Neither Rabi nor I had any idea how rapidly this would change. We are now awash in public excitement about the ''advanced fields of physics'' and, above all, about quantum mechanics. One sometimes has the feeling that much of the general public, ranging from New Age gurus to playwrights, from litera...

  5. Philosophic foundations of quantum mechanics

    CERN Document Server

    Reichenbach, Hans

    1998-01-01

    Physics concerns direct analysis of the physical world, while philosophy analyzes knowledge about the physical world. This volume combines both disciplines for a philosophical interpretation of quantum physics - an interpretation free from the imprecision of metaphysics, offering a view of the atomic world and its quantum mechanical results as concrete as the visible everyday world.Written by an internationally renowned philosopher who specialized in symbolic logic and the theory of relativity, this approach consists of three parts. The first section, which requires no background in math or p

  6. Symmetry of intramolecular quantum dynamics

    CERN Document Server

    Burenin, Alexander V

    2012-01-01

    The main goal of this book is to give a systematic description of intramolecular quantum dynamics on the basis of only the symmetry principles. In this respect, the book has no analogs in the world literature. The obtained models lead to a simple, purely algebraic, scheme of calculation and are rigorous in the sense that their correctness is limited only to the correct choice of symmetry of the internal dynamics. The book is basically intended for scientists working in the field of molecular spectroscopy, quantum and structural chemistry.

  7. Quantum interaction. Revised selected papers

    International Nuclear Information System (INIS)

    Song, Dawei; Zhang, Peng; Wang, Lei; Arafat, Sachi

    2011-01-01

    This book constitutes the thoroughly refereed post-conference proceedings of the 5th International Symposium on Quantum Interaction, QI 2011, held in Aberdeen, UK, in June 2011. The 26 revised full papers and 6 revised poster papers, presented together with 1 tutorial and 1 invited talk were carefully reviewed and selected from numerous submissions during two rounds of reviewing and improvement. The papers show the cross-disciplinary nature of quantum interaction covering topics such as computation, cognition, mechanics, social interaction, semantic space and information representation and retrieval. (orig.)

  8. Photovoltaic module with light reflecting backskin

    Science.gov (United States)

    Gonsiorawski, Ronald C.

    2007-07-03

    A photovoltaic module comprises electrically interconnected and mutually spaced photovoltaic cells that are encapsulated by a light-transmitting encapsulant between a light-transparent front cover and a back cover, with the back cover sheet being an ionomer/nylon alloy embossed with V-shaped grooves running in at least two directions and coated with a light reflecting medium so as to provide light-reflecting facets that are aligned with the spaces between adjacent cells and oriented so as to reflect light falling in those spaces back toward said transparent front cover for further internal reflection onto the solar cells, whereby substantially all of the reflected light will be internally reflected from said cover sheet back to the photovoltaic cells, thereby increasing the current output of the module. The internal reflector improves power output by as much as 67%.

  9. Quantum Secure Direct Communication with Quantum Memory

    Science.gov (United States)

    Zhang, Wei; Ding, Dong-Sheng; Sheng, Yu-Bo; Zhou, Lan; Shi, Bao-Sen; Guo, Guang-Can

    2017-06-01

    Quantum communication provides an absolute security advantage, and it has been widely developed over the past 30 years. As an important branch of quantum communication, quantum secure direct communication (QSDC) promotes high security and instantaneousness in communication through directly transmitting messages over a quantum channel. The full implementation of a quantum protocol always requires the ability to control the transfer of a message effectively in the time domain; thus, it is essential to combine QSDC with quantum memory to accomplish the communication task. In this Letter, we report the experimental demonstration of QSDC with state-of-the-art atomic quantum memory for the first time in principle. We use the polarization degrees of freedom of photons as the information carrier, and the fidelity of entanglement decoding is verified as approximately 90%. Our work completes a fundamental step toward practical QSDC and demonstrates a potential application for long-distance quantum communication in a quantum network.

  10. Quantum Secure Direct Communication with Quantum Memory.

    Science.gov (United States)

    Zhang, Wei; Ding, Dong-Sheng; Sheng, Yu-Bo; Zhou, Lan; Shi, Bao-Sen; Guo, Guang-Can

    2017-06-02

    Quantum communication provides an absolute security advantage, and it has been widely developed over the past 30 years. As an important branch of quantum communication, quantum secure direct communication (QSDC) promotes high security and instantaneousness in communication through directly transmitting messages over a quantum channel. The full implementation of a quantum protocol always requires the ability to control the transfer of a message effectively in the time domain; thus, it is essential to combine QSDC with quantum memory to accomplish the communication task. In this Letter, we report the experimental demonstration of QSDC with state-of-the-art atomic quantum memory for the first time in principle. We use the polarization degrees of freedom of photons as the information carrier, and the fidelity of entanglement decoding is verified as approximately 90%. Our work completes a fundamental step toward practical QSDC and demonstrates a potential application for long-distance quantum communication in a quantum network.

  11. Experimental quantum forgery of quantum optical money

    Science.gov (United States)

    Bartkiewicz, Karol; Černoch, Antonín; Chimczak, Grzegorz; Lemr, Karel; Miranowicz, Adam; Nori, Franco

    2017-03-01

    Unknown quantum information cannot be perfectly copied (cloned). This statement is the bedrock of quantum technologies and quantum cryptography, including the seminal scheme of Wiesner's quantum money, which was the first quantum-cryptographic proposal. Surprisingly, to our knowledge, quantum money has not been tested experimentally yet. Here, we experimentally revisit the Wiesner idea, assuming a banknote to be an image encoded in the polarization states of single photons. We demonstrate that it is possible to use quantum states to prepare a banknote that cannot be ideally copied without making the owner aware of only unauthorized actions. We provide the security conditions for quantum money by investigating the physically-achievable limits on the fidelity of 1-to-2 copying of arbitrary sequences of qubits. These results can be applied as a security measure in quantum digital right management.

  12. Ethical reflection and psychotherapy.

    Science.gov (United States)

    Vyskocilová, Jana; Prasko, Jan

    2013-01-01

    Theories of ethics and ethical reflection may be applied to both theory and practice in psychotherapy. There is a natural affinity between ethics and psychotherapy. Psychotherapy practice is concerned with human problems, dilemmas and emotions related to both one's own and other people's values. Ethics is also concerned with dilemmas in human thinking and with how these dilemmas reflect other individuals' values. Philosophical reflection itself is not a sufficient basis for the ethics of psychotherapy but it may aid in exploring attitudes related to psychotherapy, psychiatry and health care. PubMed, Web of Science and Scopus databases were searched for articles containing the keywords "psychotherapy", "ethics", "therapeutic relationship" and "supervision". The search was conducted by repeating the terms in various combinations without language or time restrictions. Also included were data from monographs cited in reviews. The resulting text is a review with conclusions concerning ethical aspects of psychotherapy. The ability to behave altruistically, sense for justice and reciprocity and mutual help are likely to be genetically determined as dispositions to be later developed by upbringing or to be formed or deformed by upbringing. Early experiences lead to formation of ethical attitudes which are internalized and then applied to both one's own and other people's behavior. Altruistic behavior has a strong impact on an individual's health and its acceptance may positively influence the pathophysiological mechanisms underlying numerous diseases. Ethical theory and reflection, however, may be applied to both theory and practice of psychotherapy in a conscious, targeted and thoughtful manner. In everyday practice, psychotherapists and organizations must necessarily deal with conscious conflicts between therapeutic possibilities, clients' wishes, their own as well as clients' ideas and the real world. Understanding one's own motives in therapy is one of the aims of a

  13. Solvable Quantum Macroscopic Motions and Decoherence Mechanisms in Quantum Mechanics on Nonstandard Space

    Science.gov (United States)

    Kobayashi, Tsunehiro

    1996-01-01

    Quantum macroscopic motions are investigated in the scheme consisting of N-number of harmonic oscillators in terms of ultra-power representations of nonstandard analysis. Decoherence is derived from the large internal degrees of freedom of macroscopic matters.

  14. News Education: Physics Education Networks meeting has global scale Competition: Competition seeks the next Brian Cox Experiment: New measurement of neutrino time-of-flight consistent with the speed of light Event: A day for all those who teach physics Conference: Students attend first Anglo-Japanese international science conference Celebration: Will 2015 be the 'Year of Light'? Teachers: Challenging our intuition in spectacular fashion: the fascinating world of quantum physics awaits Research: Science sharpens up sport Learning: Kittinger and Baumgartner: on a mission to the edge of space International: London International Youth Science Forum calls for leading young scientists Competition: Physics paralympian challenge needs inquisitive, analytical, artistic and eloquent pupils Forthcoming events

    Science.gov (United States)

    2012-05-01

    Education: Physics Education Networks meeting has global scale Competition: Competition seeks the next Brian Cox Experiment: New measurement of neutrino time-of-flight consistent with the speed of light Event: A day for all those who teach physics Conference: Students attend first Anglo-Japanese international science conference Celebration: Will 2015 be the 'Year of Light'? Teachers: Challenging our intuition in spectacular fashion: the fascinating world of quantum physics awaits Research: Science sharpens up sport Learning: Kittinger and Baumgartner: on a mission to the edge of space International: London International Youth Science Forum calls for leading young scientists Competition: Physics paralympian challenge needs inquisitive, analytical, artistic and eloquent pupils Forthcoming events

  15. Gamma camera with reflectivity mask

    International Nuclear Information System (INIS)

    Stout, K.J.

    1980-01-01

    In accordance with the present invention there is provided a radiographic camera comprising: a scintillator; a plurality of photodectors positioned to face said scintillator; a plurality of masked regions formed upon a face of said scintillator opposite said photdetectors and positioned coaxially with respective ones of said photodetectors for decreasing the amount of internal reflection of optical photons generated within said scintillator. (auth)

  16. Fractional Quantum Hall States in a Ge Quantum Well.

    Science.gov (United States)

    Mironov, O A; d'Ambrumenil, N; Dobbie, A; Leadley, D R; Suslov, A V; Green, E

    2016-04-29

    Measurements of the Hall and dissipative conductivity of a strained Ge quantum well on a SiGe/(001)Si substrate in the quantum Hall regime are reported. We analyze the results in terms of thermally activated quantum tunneling of carriers from one internal edge state to another across saddle points in the long-range impurity potential. This shows that the gaps for different filling fractions closely follow the dependence predicted by theory. We also find that the estimates of the separation of the edge states at the saddle are in line with the expectations of an electrostatic model in the lowest spin-polarized Landau level (LL), but not in the spin-reversed LL where the density of quasiparticle states is not high enough to accommodate the carriers required.

  17. Quantum Locality?

    Energy Technology Data Exchange (ETDEWEB)

    Stapp, Henry

    2011-11-10

    Robert Griffiths has recently addressed, within the framework of a ‘consistent quantum theory’ (CQT) that he has developed, the issue of whether, as is often claimed, quantum mechanics entails a need for faster-than-light transfers of information over long distances. He argues, on the basis of his examination of certain arguments that claim to demonstrate the existence of such nonlocal influences, that such influences do not exist. However, his examination was restricted mainly to hidden-variable-based arguments that include in their premises some essentially classical-physics-type assumptions that are fundamentally incompatible with the precepts of quantum physics. One cannot logically prove properties of a system by attributing to the system properties alien to that system. Hence Griffiths’ rejection of hidden-variable-based proofs is logically warranted. Griffiths mentions the existence of a certain alternative proof that does not involve hidden variables, and that uses only macroscopically described observable properties. He notes that he had examined in his book proofs of this general kind, and concluded that they provide no evidence for nonlocal influences. But he did not examine the particular proof that he cites. An examination of that particular proof by the method specified by his ‘consistent quantum theory’ shows that the cited proof is valid within that restrictive framework. This necessary existence, within the ‘consistent’ framework, of long range essentially instantaneous influences refutes the claim made by Griffiths that his ‘consistent’ framework is superior to the orthodox quantum theory of von Neumann because it does not entail instantaneous influences. An added section responds to Griffiths’ reply, which cites a litany of ambiguities that seem to restrict, devastatingly, the scope of his CQT formalism, apparently to buttress his claim that my use of that formalism to validate the nonlocality theorem is flawed. But the

  18. Elementary quantum chemistry

    CERN Document Server

    Pilar, Frank L

    2003-01-01

    Useful introductory course and reference covers origins of quantum theory, Schrödinger wave equation, quantum mechanics of simple systems, electron spin, quantum states of atoms, Hartree-Fock self-consistent field method, more. 1990 edition.

  19. Optical quantum memory

    Science.gov (United States)

    Lvovsky, Alexander I.; Sanders, Barry C.; Tittel, Wolfgang

    2009-12-01

    Quantum memory is essential for the development of many devices in quantum information processing, including a synchronization tool that matches various processes within a quantum computer, an identity quantum gate that leaves any state unchanged, and a mechanism to convert heralded photons to on-demand photons. In addition to quantum computing, quantum memory will be instrumental for implementing long-distance quantum communication using quantum repeaters. The importance of this basic quantum gate is exemplified by the multitude of optical quantum memory mechanisms being studied, such as optical delay lines, cavities and electromagnetically induced transparency, as well as schemes that rely on photon echoes and the off-resonant Faraday interaction. Here, we report on state-of-the-art developments in the field of optical quantum memory, establish criteria for successful quantum memory and detail current performance levels.

  20. Indirect absorption spectroscopy using quantum cascade lasers: mid-infrared refractometry and photothermal spectroscopy.

    Science.gov (United States)

    Pfeifer, Marcel; Ruf, Alexander; Fischer, Peer

    2013-11-04

    We record vibrational spectra with two indirect schemes that depend on the real part of the index of refraction: mid-infrared refractometry and photothermal spectroscopy. In the former, a quantum cascade laser (QCL) spot is imaged to determine the angles of total internal reflection, which yields the absorption line via a beam profile analysis. In the photothermal measurements, a tunable QCL excites vibrational resonances of a molecular monolayer, which heats the surrounding medium and changes its refractive index. This is observed with a probe laser in the visible. Sub-monolayer sensitivities are demonstrated.