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| Author | Казаков, А. Ю.; Кардакова, А. И.; Селиверстов, С. В.; Горшков, К. Н.; Дивочий, А. В.; Финкель, М. И.; Корнеев, А. А.; Вахтомин, Ю. Б. | ||||
| Title | Возможность применения сверхпроводниковых материалов в качестве отражающего покрытия холодного зеркала телескопа субмиллиметрового диапазона | Type | Journal Article | ||
| Year | 2012 | Publication | Совр. проб. науки и обр. | Abbreviated Journal | Совр. проб. науки и обр. |
| Volume | Issue | 3 | Pages | 1-5 | |
| Keywords | radio telescope, superconducting coating | ||||
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russian | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 2070-7428 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | УДК 520.272.2 | Approved | no | ||
| Call Number | RPLAB @ sasha @ казаковвозможность | Serial | 1030 | ||
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| Author | Семенов, А. В.; Корнеев, А. А.; Лобанов, Ю. В.; Корнеева, Ю. П.; Рябчун, С. А.; Лаврова, О. С.; Третьяков, И. В.; Флоря, И. Н.; Силаев, М. А.; Кинев, Н. В.; Ковалюк, В. В.; Смирнов, К. В.; Гольцман, Г. Н. | ||||
| Title | Поляризация электромагнитной волны вблизи фокуса зеркала и системы зеркал в субтерагерцовом диапазоне частот | Type | Journal Article | ||
| Year | 2012 | Publication | Современные проблемы науки и образования | Abbreviated Journal | |
| Volume | Issue | 2 | Pages | ||
| Keywords | sub-terahertz radio telescope | ||||
| Abstract | Рассмотрено влияние оптической системы телескопа на поляризацию принимаемого электромагнитного сигнала. Описано изменение поляризации луча при отражении от произвольно ориентированной поверхности зеркала. Учтены искажения поляризации, обусловленные как отклонением лучей от первоначального направления, так и различием в коэффициентах отражения для разных поляризаций в случае неидеального отражения. В рамках метода Френеля получены оценочные формулы, дающие отношение амплитуд поля с исходной поляризацией и с поляризацией, перпендикулярной исходной, вблизи фокальной точки оптической системы. Формулы выведены для нескольких практически важных случаев, в том числе для параболического зеркала и системы двух зеркал. Оценена верхняя граница поляризационных искажений в пределах кружка Эйри. Полученные оценки согласуются с результатами численного расчёта для двухзеркального радиотелескопа субтерагерцового диапазона. | ||||
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Russian | Summary Language | Original Title | ||
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| Notes | 9 страниц; УДК 535-47 | Approved | no | ||
| Call Number | Serial | 1819 | |||
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| Author | Казаков, А. Ю.; Селиверстов, С. В.; Дивочий, А. В.; Смирнов, К. В.; Финкель, М. И.; Вахтомин, Ю. Б. | ||||
| Title | Возможность применения сверхпроводниковых материалов в качестве отражающего покрытия зеркала телескопа, предназначенного для наблюдений анизотропии реликтового излучения | Type | Journal Article | ||
| Year | 2012 | Publication | Преподаватель ХХI век | Abbreviated Journal | |
| Volume | Issue | 3 | Pages | 221-224 | |
| Keywords | submillimeter radio telescope | ||||
| Abstract | В статье исследуется возможность использования сверхпроводящего материала в качестве отражающего слоя зеркала субмиллиметрового телескопа, охлажденного до криогенных температур и предназначенного для наблюдений реликтового излучения. Для нескольких сверхпроводниковых материалов вычислен диапазон частот, в котором флуктуации теплового излучения покрытия меньше флуктуаций источника. Показана перспективность применения покрытия из Nb3Ge. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1820 | |||
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| Author | Семенов, А. В.; Корнеев, А. А.; Лобанов, Ю. В.; Корнеева, Ю. П.; Рябчун, С. А.; Третьяков, И. В.; Флоря, И. Н.; Смирнов, А. В.; Ковалюк, В. В.; Смирнов, К. В.; Гольцман, Г. Н. | ||||
| Title | Оценка поляризационных искажений, вносимых оптической системой радиотелескопа миллиметрового диапазона | Type | Journal Article | ||
| Year | 2012 | Publication | Преподаватель ХХI век | Abbreviated Journal | |
| Volume | Issue | 4 | Pages | 230-236 | |
| Keywords | millimeter radio telescope | ||||
| Abstract | В статье рассмотрена поляризация электромагнитного поля вблизи фокальной точки телескопической системы. Оценена верхняя граница поляризационных искажений, вносимых отражающими поверхностями, в том числе с учетом неидеальности отражения. | ||||
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Russian | Summary Language | Original Title | ||
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| Notes | Approved | no | |||
| Call Number | Serial | 1821 | |||
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| Author | Семенов, А. В.; Корнеев, А. А.; Смирнов, А. В.; Смирнов, К. В.; Ожегов, Р. В.; Окунев, О. В.; Гольцман, Г. Н.; Девятов, И. А. | ||||
| Title | Линейные по мощности поглощаемого излучения поправки к спектральным функциям «грязного» сверхпроводника и отклик сверхпроводниковых детекторов | Type | Journal Article | ||
| Year | 2012 | Publication | Преподаватель ХХI век | Abbreviated Journal | |
| Volume | Issue | 3 | Pages | 216-220 | |
| Keywords | dirty superconductor film | ||||
| Abstract | В статье развит метод расчета малых поправок к спектральным функциям пленки «грязного» сверхпроводника, возникающих под действием поглощаемой мощности электромагнитного излучения. Метод пригоден в случае спектральных функций произвольного вида, что позволяет применять его для расчета отклика сверхпроводниковых детекторов излучения различного типа. | ||||
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Russian | Summary Language | Original Title | ||
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| Notes | Approved | no | |||
| Call Number | Serial | 1822 | |||
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| Author | Корнеева, Ю. П.; Трифонов, А. В.; Вахтомин, Ю. Б.; Смирнов, К. В.; Корнеев, А. А.; Рябчун, С. А.; Третьяков, И. В.; Гольцман, Г. Н. | ||||
| Title | Расчет согласующего оптического резонатора для сверхпроводникового нанополоскового детектора | Type | Journal Article | ||
| Year | 2012 | Publication | Преподаватель ХХI век | Abbreviated Journal | |
| Volume | Issue | 3 | Pages | 225-227 | |
| Keywords | SSPD, SNSPD | ||||
| Abstract | В статье произведен расчет резонатора, предназначенного для согласования сверхпроводникового нанополоскового однофотонного детектора с оптическим сигналом. Показано, что для детектора, выполненного из пленки с типичным сопротивлением квадрата 500 Ом и коэффициентом заполнения 0.5 коэффициент согласования с излучением, поляризованным параллельно полоскам детектора, достигает величины около 60%. | ||||
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Russian | Summary Language | Original Title | ||
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| Notes | Approved | no | |||
| Call Number | Serial | 1823 | |||
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| Author | Semenov, A. V.; Devyatov, I. A.; Korneev, A. A.; Smirnov, K. V.; Goltsman, G. N.; Melnikov, A. P. | ||||
| Title | Derivation of expression for thermodynamic potential of “dirty” superconductor | Type | Journal Article | ||
| Year | 2012 | Publication | Rus. J. Radio Electron. | Abbreviated Journal | Rus. J. Radio Electron. |
| Volume | Issue | 4 | Pages | ||
| Keywords | dirty superconductor, Usadel theory, thermodynamic potential | ||||
| Abstract | We derive a formula for thermodynamic potential of dirty superconductor which express it via isotropic quasiclassical Green functions of Usadel theory. Our result allows unify description of dynamic processes and fluctuations in superconducting nano-electronic devices. | ||||
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Russian | Summary Language | Original Title | ||
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| Notes | 7 pages | Approved | no | ||
| Call Number | Serial | 1824 | |||
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| Author | Смирнов, А. В.; Карманцов, М. С.; Смирнов, К. В.; Вахтомин, Ю. Б.; Мастеров, Д. В.; Тархов, М. А.; Павлов, С. А.; Парафин, А. Е. | ||||
| Title | Терагерцовый отклик болометров на основе тонких пленок YBCO | Type | Journal Article | ||
| Year | 2012 | Publication | ЖТФ | Abbreviated Journal | ЖТФ |
| Volume | 82 | Issue | 12 | Pages | 108-111 |
| Keywords | YBCO HEB NEP | ||||
| Abstract | Представлены первые результаты измерения болометрического отклика высокотемпературных сверхпроводниковых детекторов на основе тонких пленок YBCO на электромагнитное излучение с частотой 2.5 THz. Минимальное значение оптической мощности, эквивалентной шуму созданных детекторов, составило 3.5· 10-9 W/sqrt(Hz)sqrt. Обсуждена возможность дальнейшего увеличения чувствительности исследуемых детекторов. | ||||
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Russian | Summary Language | Original Title | ||
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| Notes | Approved | no | |||
| Call Number | Serial | 1825 | |||
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| Author | Чулкова, Галина Меркурьевна; Семёнов, Александр Владимирович; Тархов, Михаил Александрович; Гольцман, Григорий Наумович; Корнеев, Александр Александрович; Смирнов, Константин Владимирович | ||||
| Title | О возможности использования PNR-SNPD в системах телекоммуникационной связи | Type | Journal Article | ||
| Year | 2012 | Publication | Преподаватель ХХI век | Abbreviated Journal | |
| Volume | Issue | 2 | Pages | 244-246 | |
| Keywords | PNR SSPD, SNSPD, SNPD | ||||
| Abstract | Рассмотрена возможность применения сверхпроводникового нанополоскового детектора, разрешающего число фотонов (Photon-Number Resolving Superconducting Nanowire Photon Detector, PNR-SNPD), в качестве датчика приёмных модулей телекоммуникационных линий. Оценена мощность оптического импульса, необходимая для достижения приемлемо низкой доли ошибочных битов. | ||||
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Russian | Summary Language | Original Title | ||
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| Notes | Approved | no | |||
| Call Number | Serial | 1826 | |||
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| Author | Henrich, D.; Dorner,S.; Hofherr, M.; Il'in, K.; Semenov, A.; Heintze, E.; Scheffler, M.; Dressel, M.; Siegel, M. | ||||
| Title | Broadening of hot-spot response spectrum of superconducting NbN nanowire single-photon detector with reduced nitrogen content | Type | Journal Article | ||
| Year | 2012 | Publication | Abbreviated Journal | J. Appl. Phys. | |
| Volume | 112 | Issue | Pages | ||
| Keywords | SSPD, SNSPD, magnetron sputtering, spectrum, NbN film, nitrogen concentration | ||||
| Abstract | The spectral detection efficiency and the dark count rate of superconducting nanowire single-photon detectors (SNSPD) have been studied systematically on detectors made from thin NbN films with different chemical compositions. Reduction of the nitrogen content in the 4 nm thick NbN films results in a decrease of the dark count rates more than two orders of magnitude and in a red shift of the cut-off wavelength of the hot-spot SNSPD response. The observed phenomena are explained by an improvement of uniformity of NbN films that has been confirmed by a decrease of resistivity and an increase of the ratio of the measured critical current to the depairing current. The latter factor is considered as the most crucial for both the cut-off wavelength and the dark count rates of SNSPD. Based on our results we propose a set of criteria for material properties to optimize SNSPD in the infrared spectral region. VC 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4757625] |
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| Corporate Author | D. Henrich, S. Dorner, M. Hofherr, K. Il'in, A. Semenov, E. Heintze, M. Scheffler, M. Dressel, M. Siegel | Thesis | |||
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English | Summary Language | Original Title | Broadening of hot-spot response spectrum of superconducting NbN nanowire single-photon detector with reduced nitrogen content | |
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| Notes | Approved | no | |||
| Call Number | RPLAB @ seleznev @ | Serial | 877 | ||
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| Author | Sclafani, M.; Marksteiner, M.; Keir, F. M. L.; Divochiy, A.; Korneev, A.; Semenov, A.; Gol'tsman, G.; Arndt, M. | ||||
| Title | Sensitivity of a superconducting nanowire detector for single ions at low energy | Type | Journal Article | ||
| Year | 2012 | Publication | Nanotechnol. | Abbreviated Journal | Nanotechnol. |
| Volume | 23 | Issue | 6 | Pages | 065501 (1 to 5) |
| Keywords | NbN SSPD, SNSPD, superconducting single ion detector, SSID, SNSID | ||||
| Abstract | We report on the characterization of a superconducting nanowire detector for ions at low kinetic energies. We measure the absolute single-particle detection efficiency eta and trace its increase with energy up to eta = 100%. We discuss the influence of noble gas adsorbates on the cryogenic surface and analyze their relevance for the detection of slow massive particles. We apply a recent model for the hot-spot formation to the incidence of atomic ions at energies between 0.2 and 1 keV. We suggest how the differences observed for photons and atoms or molecules can be related to the surface condition of the detector and we propose that the restoration of proper surface conditions may open a new avenue for SSPD-based optical spectroscopy on molecules and nanoparticles. | ||||
| Address | Vienna Center for Quantum Science and Technology, Faculty of Physics, University of Vienna, Vienna, Austria | ||||
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English | Summary Language | Original Title | ||
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| ISSN | 0957-4484 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:22248823 | Approved | no | ||
| Call Number | Serial | 1380 | |||
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| Author | Bulaevskii, L. N.; Graf, Matthias J.; Kogan, V. G. | ||||
| Title | Vortex-assisted photon counts and their magnetic field dependence in single-photon superconducting detectors | Type | Journal Article | ||
| Year | 2012 | Publication | Phys. Rev. B | Abbreviated Journal | Phys. Rev. B |
| Volume | 85 | Issue | 1 | Pages | 9 |
| Keywords | SSPD; SNSPD; single-vortex crossing; normal-state belt | ||||
| Abstract | We argue that photon counts in a superconducting nanowire single-photon detector (SNSPD) are caused by the transition from a current-biased metastable superconducting state to the normal state. Such a transition is triggered by vortices crossing the thin and narrow superconducting strip from one edge to another due to the Lorentz force. Detector counts in SNSPDs may be caused by three processes: (a) a single incident photon with sufficient energy to break enough Cooper pairs to create a normal-state belt across the entire width of the strip (direct photon count), (b) thermally induced single-vortex crossing in the absence of photons (dark count), which at high-bias currents releases the energy sufficient to trigger the transition to the normal state in a belt across the whole width of the strip, and (c) a single incident photon of insufficient energy to create a normal-state belt but initiating a subsequent single-vortex crossing, which provides the rest of the energy needed to create the normal-state belt (vortex-assisted single-photon count). We derive the current dependence of the rate of vortex-assisted photon counts. The resulting photon count rate has a plateau at high currents close to the critical current and drops as a power law with high exponent at lower currents. While the magnetic field perpendicular to the film plane does not affect the formation of hot spots by photons, it causes the rate of vortex crossings (with or without photons) to increase. We show that by applying a magnetic field one may characterize the energy barrier for vortex crossings and identify the origin of dark counts and vortex-assisted photon counts. | ||||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ gujma @ | Serial | 733 | ||
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| Author | Knee, George C.; Simmons, Stephanie; Gauger, Erik M.; Morton, John J. L.; Riemann, Helge; Abrosimov, Nikolai V.; Becker, Peter; Pohl, Hans-Joachim; Itoh, Kohei M.; Thewalt, Mike L. W.; Briggs, G. Andrew D.; Benjamin, Simon C. | ||||
| Title | Violation of a Leggett–Garg inequality with ideal non-invasive measurements | Type | Journal Article | ||
| Year | 2012 | Publication | Nature Communications | Abbreviated Journal | Nat. Comm. |
| Volume | 3 | Issue | 606 | Pages | 6 |
| Keywords | fromIPMRAS | ||||
| Abstract | The quantum superposition principle states that an entity can exist in two different states simultaneously, counter to our 'classical' intuition. Is it possible to understand a given system's behaviour without such a concept? A test designed by Leggett and Garg can rule out this possibility. The test, originally intended for macroscopic objects, has been implemented in various systems. However to date no experiment has employed the 'ideal negative result' measurements that are required for the most robust test. Here we introduce a general protocol for these special measurements using an ancillary system, which acts as a local measuring device but which need not be perfectly prepared. We report an experimental realization using spin-bearing phosphorus impurities in silicon. The results demonstrate the necessity of a non-classical picture for this class of microscopic system. Our procedure can be applied to systems of any size, whether individually controlled or in a spatial ensemble. | ||||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ gujma @ | Serial | 767 | ||
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| Author | Smith, Devin H.; Gillett, Geoff; de Almeida, Marcelo P.; Branciard, Cyril; Fedrizzi, Alessandro; Weinhold, Till J.; Lita, Adriana; Calkins, Brice; Gerrits, Thomas; Wiseman, Howard M.; Nam, Sae Woo; White, Andrew G. | ||||
| Title | Conclusive quantum steering with superconducting transition-edge sensors | Type | Journal Article | ||
| Year | 2012 | Publication | Nature Communications | Abbreviated Journal | Nat. Comm. |
| Volume | 3 | Issue | 625 | Pages | 6 |
| Keywords | fromIPMRAS | ||||
| Abstract | Quantum steering allows two parties to verify shared entanglement even if one measurement device is untrusted. A conclusive demonstration of steering through the violation of a steering inequality is of considerable fundamental interest and opens up applications in quantum communication. To date, all experimental tests with single-photon states have relied on post selection, allowing untrusted devices to cheat by hiding unfavourable events in losses. Here we close this 'detection loophole' by combining a highly efficient source of entangled photon pairs with superconducting transition-edge sensors. We achieve an unprecedented ~62% conditional detection efficiency of entangled photons and violate a steering inequality with the minimal number of measurement settings by 48 s.d.s. Our results provide a clear path to practical applications of steering and to a photonic loophole-free Bell test. | ||||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ gujma @ | Serial | 768 | ||
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| Author | Ghali, Mohsen; Ohtani1, Keita; Ohno, Yuzo; Ohno, Hideo | ||||
| Title | Generation and control of polarization-entangled photons from GaAs island quantum dots by an electric field | Type | Journal Article | ||
| Year | 2012 | Publication | Nature Communications | Abbreviated Journal | Nat. Comm. |
| Volume | 3 | Issue | 661 | Pages | 6 |
| Keywords | fromIPMRAS | ||||
| Abstract | Semiconductor quantum dots are potential sources for generating polarization-entangled photons efficiently. The main prerequisite for such generation based on biexciton-exciton cascaded emission is to control the exciton fine-structure splitting. Among various techniques investigated for this purpose, an electric field is a promising means to facilitate the integration into optoelectronic devices. Here we demonstrate the generation of polarization-entangled photons from single GaAs quantum dots by an electric field. In contrast to previous studies, which were limited to In(Ga)As quantum dots, GaAs island quantum dots formed by a thickness fluctuation were used because they exhibit a larger oscillator strength and emit light with a shorter wavelength. A forward voltage was applied to a Schottky diode to control the fine-structure splitting. We observed a decrease and suppression in the fine-structure splitting of the studied single quantum dot with the field, which enabled us to generate polarization-entangled photons with a high fidelity of 0.72 ± 0.05. | ||||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ gujma @ | Serial | 769 | ||
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