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Author | Mohan, N.; Minaeva, O.; Gol'tsman, G. N.; Nasr, M. B.; Saleh, B. E.; Sergienko, A. V.; Teich, M. C. | ||||
Title | Photon-counting optical coherence-domain reflectometry using superconducting single-photon detectors | Type | Journal Article | ||
Year | 2008 | Publication | Opt. Express | Abbreviated Journal | Opt. Express |
Volume | 16 | Issue | 22 | Pages | 18118-18130 |
Keywords | SSPD, SNSPD | ||||
Abstract | We consider the use of single-photon counting detectors in coherence-domain imaging. Detectors operated in this mode exhibit reduced noise, which leads to increased sensitivity for weak light sources and weakly reflecting samples. In particular, we experimentally demonstrate the possibility of using superconducting single-photon detectors (SSPDs) for optical coherence-domain reflectometry (OCDR). These detectors are sensitive over the full spectral range that is useful for carrying out such imaging in biological samples. With counting rates as high as 100 MHz, SSPDs also offer a high rate of data acquisition if the light flux is sufficient. | ||||
Address | Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA. nm82@bu.edu | ||||
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ISSN | 1094-4087 | ISBN | Medium | ||
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Notes | PMID:18958090 | Approved | no | ||
Call Number | Serial | 1407 | |||
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Author | Finkel, M. I.; Maslennikov, S. N.; Gol'tsman, G. N. | ||||
Title | The concept of the receiving complex for the “Millimetron” space radio telescope | Type | Journal Article | ||
Year | 2007 | Publication | Radiophys. Quant. Electron. | Abbreviated Journal | Radiophys. Quant. Electron. |
Volume | 50 | Issue | 10-11 | Pages | 837-846 |
Keywords | HEB, applications, Millimetron, VLBI | ||||
Abstract | We consider the current status of research in the development of a submillimeter and far-infrared receiving instrument and propose promising solutions for the receivers of the spaceborne telescope “Millimetron,” which allow one to realize comprehensively the opportunities given by this international project administrated by the Astrospace Center of the P. N. Lebedev Physical Institute of the Russian Academy of Sciences. | ||||
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ISSN | 0033-8443 | ISBN | Medium | ||
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Notes | Approved | no | |||
Call Number | Serial | 411 | |||
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Author | Ryzhii, V.; Otsuji, T.; Ryzhii, M.; Leiman, V. G.; Fedorov, G.; Goltzman, G. N.; Gayduchenko, I. A.; Titova, N.; Coquillat, D.; But, D.; Knap, W.; Mitin, V.; Shur, M. S. | ||||
Title | Two-dimensional plasmons in lateral carbon nanotube network structures and their effect on the terahertz radiation detection | Type | Journal Article | ||
Year | 2016 | Publication | J. Appl. Phys. | Abbreviated Journal | J. Appl. Phys. |
Volume | 120 | Issue | 4 | Pages | 044501 (1 to 13) |
Keywords | carbon nanotubes, CNT detectors, plasmons | ||||
Abstract | We consider the carrier transport and plasmonic phenomena in the lateral carbon nanotube (CNT) networks forming the device channel with asymmetric electrodes. One electrode is the Ohmic contact to the CNT network and the other contact is the Schottky contact. These structures can serve as detectors of the terahertz (THz) radiation. We develop the device model for collective response of the lateral CNT networks which comprise a mixture of randomly oriented semiconductor CNTs (s-CNTs) and quasi-metal CNTs (m-CNTs). The proposed model includes the concept of the collective two-dimensional (2D) plasmons in relatively dense networks of randomly oriented CNTs (CNT “felt”) and predicts the detector responsivity spectral characteristics exhibiting sharp resonant peaks at the signal frequencies corresponding to the 2D plasmonic resonances. The detection mechanism is the rectification of the ac current due the nonlinearity of the Schottky contact current-voltage characteristics under the conditions of a strong enhancement of the potential drop at this contact associated with the plasmon excitation. The detector responsivity depends on the fractions of the s- and m-CNTs. The burning of the near-contact regions of the m-CNTs or destruction of these CNTs leads to a marked increase in the responsivity in agreement with our experimental data. The resonant THz detectors with sufficiently dense lateral CNT networks can compete and surpass other THz detectors using plasmonic effects at room temperatures. | ||||
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ISSN | 0021-8979 | ISBN | Medium | ||
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Notes | Approved | no | |||
Call Number | Serial | 1777 | |||
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Author | Finkel, M. I.; Maslennikov, S. N.; Gol'tsman, G. N. | ||||
Title | Terahertz heterodyne receivers based on superconductive hot-electron bolometer mixers | Type | Journal Article | ||
Year | 2005 | Publication | Radiophys. Quant. Electron. | Abbreviated Journal | Radiophys. Quant. Electron. |
Volume | 48 | Issue | 10-11 | Pages | 859-864 |
Keywords | HEB, applications | ||||
Abstract | We consider recent results in development of hot-electron bolometer mixers. Special attention is paid to optimization of the contacts between the antenna and the active area of a superconducting film. An important result in the study of the parasitic effect of direct detection is obtained during the measurement of the noise temperatures by the hot/cold load method. The latest results of studies of the waveguide hot-electron bolometer mixers and their successful practical applications are considered. Progress in development of high-frequency (over 1.3 THz) heterodyne receivers for several important international projects is discussed and new submillimeter radio astronomy projects ESPRIT and SAFIR are described. | ||||
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ISSN | 0033-8443 | ISBN | Medium | ||
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Notes | Approved | no | |||
Call Number | Serial | 381 | |||
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Author | Чулкова, Г. М.; Семенов, А. В.; Корнеев, А. А.; Кардакова, А. И.; Аверьев, Н. В.; Ан, П. П.; Казаков, А. Ю.; Трифонов, А. В. | ||||
Title | Спектральная чувствительность сверхпроводникового однофотонного детектора | Type | Journal Article | ||
Year | 2011 | Publication | Журнал радиоэлектроники | Abbreviated Journal | Ж. радиоэлектрон. |
Volume | 11 | Issue | Pages | 5 | |
Keywords | SSPD; quantum efficiency; spectral sensitivity | ||||
Abstract | We consider quantum efficiency dependence on photons' energy from hot spot model. Direction of quasiparticles diffusion drive across superconductive film. The maximal quantum efficiency is proportional to a probability of photon absorption. The spectral sensitivity of superconductive single photon detector does not have clearly expressed red limit. Changing regimes of work depends on a wavelength we can get high values of quantum efficiency in visible and infrared range which will be specified by the quality of fabrication of detectors and their consistency with the radiation. Key words: superconducting single-photon detector, SSPD, quantum efficiency, spectral sensitivity. В статье представлена зависимость квантовой эффективности от энергии фотона в рамках модели горячего пятна. Диффузия квазичастиц происходит в основном перпендикулярно направлению тока в областях с максимальной плотностью тока. Максимальная квантовая эффективность детектора пропорциональна вероятности поглощения фотона. Несмотря на квантовый характер работы сверхпроводникового однофотонного детектора, он не имеет четко выраженной красной границы. Изменяя режим работы в зависимости от длины волны можно в видимом и инфракрасном диапазонах получать высокие значения квантовой эффективности, которые будут определяться лишь качеством изготовления детекторов и степенью их согласования с излучением. |
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Call Number | RPLAB @ gujma @ | Serial | 844 | ||
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Author | Tikhonov, V. V.; Polyakova, O. N.; Gol’tsman, G. N.; Dzardanov, A. L.; Boyarskiy, D. A. | ||||
Title | Determination of dielectric properties of ore minerals in the microwave band | Type | Journal Article | ||
Year | 2008 | Publication | Radiophys. Quant. Electron. | Abbreviated Journal | Radiophys. Quant. Electron. |
Volume | 51 | Issue | 12 | Pages | 966-974 |
Keywords | ore complex permittivity, chalcopyrite, magnetite, sphalerite, labradorite | ||||
Abstract | We consider a method for determining the complex dielectric permittivity of ore and nonmetal minerals in the microwave band of electromagnetic radiation. The results of measuring the reflectivity and transmittivity of chalcopyrite, magnetite, sphalerite, and labradorite samples in the frequency range 77–300 GHz are presented. A method for calculation of the complex dielectric permittivity of minerals on the basis of the obtained experimental data is proposed. The approximation formulas for calculation of the complex dielectric permittivity of the studied minerals are given. | ||||
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ISSN | 0033-8443 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1404 | |||
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Author | Seliverstov, S.; Maslennikov, S.; Ryabchun, S.; Finkel, M.; Klapwijk, T. M.; Kaurova, N.; Vachtomin, Yu.; Smirnov, K.; Voronov, B.; Goltsman, G. | ||||
Title | Fast and sensitive terahertz direct detector based on superconducting antenna-coupled hot electron bolometer | Type | Journal Article | ||
Year | 2015 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
Volume | 25 | Issue | 3 | Pages | 2300304 |
Keywords | HEB detector responsivity, HEB model, numerical calculations, numerical model | ||||
Abstract | We characterize superconducting antenna-coupled hot-electron bolometers for direct detection of terahertz radiation operating at a temperature of 9.0 K. The estimated value of responsivity obtained from lumped-element theory is strongly different from the measured one. A numerical calculation of the detector responsivity is developed, using the Euler method, applied to the system of heat balance equations written in recurrent form. This distributed element model takes into account the effect of nonuniform heating of the detector along its length and provides results that are in better agreement with the experiment. At a signal frequency of 2.5 THz, the measured value of the optical detector noise equivalent power is 2.0 × 10-13 W · Hz-0.5. The value of the bolometer time constant is 35 ps. The corresponding energy resolution is about 3 aJ. This detector has a sensitivity similar to that of the state-of-the-art sub-millimeter detectors operating at accessible cryogenic temperatures, but with a response time several orders of magnitude shorter. | ||||
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Notes | Approved | no | |||
Call Number | Serial | 953 | |||
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Author | de Lara, D. Perez; Ejrnaes, M.; Casaburi, A.; Lisitskiy, M.; Cristiano, R.; Pagano, S.; Gaggero, A.; Leoni, R.; Golt’sman, G.; Voronov, B. | ||||
Title | Feasibility investigation of NbN nanowires as detector in time-of-flight mass spectrometers for macromolecules of interest in biology (proteins) | Type | Journal Article | ||
Year | 2008 | Publication | J. Low Temp. Phys. | Abbreviated Journal | J. Low Temp. Phys. |
Volume | 151 | Issue | 3-4 | Pages | 771-776 |
Keywords | NbN SSPD, SNSPD, nanowires | ||||
Abstract | We are investigating the possibility of using NbN nanowires as detectors in time-of-flight mass spectrometers for investigation of macromolecules of interest in biology (proteins). NbN nanowires could overcome the two major drawbacks encountered so far by cryogenic detectors, namely the low working temperature in the mK region and the slow temporal response. In fact, NbN nanowires can work at 5 K and the response time is at least a factor 10–100 better than that of other cryogenic detectors. We present a feasibility study based on a numerical code to calculate the response of a NbN nanowire. The parameter space is investigated at different energies from IR to macromolecules (i.e. from eV to keV) in order to understand if larger value of film thickness and width can be used for the keV energy region. We also present preliminary experimental results of irradiation with X-ray photons of NbN to simulate the effect of macromolecules of the same energy. | ||||
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ISSN | 0022-2291 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1410 | |||
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Author | Semenov, A.; Engel, A.; Il'in, K.; Gol'tsman, G.; Siegel, M.; Hübers, H.-W. | ||||
Title | Ultimate performance of a superconducting quantum detector | Type | Journal Article | ||
Year | 2003 | Publication | Eur. Phys. J. Appl. Phys. | Abbreviated Journal | Eur. Phys. J. Appl. Phys. |
Volume | 21 | Issue | 3 | Pages | 171-178 |
Keywords | NbN SSPD, SNSPD | ||||
Abstract | We analyze the ultimate performance of a superconducting quantum detector in order to meet requirements for applications in near-infrared astronomy and X-ray spectroscopy. The detector exploits a combined detection mechanism, in which avalanche quasiparticle multiplication and the supercurrent jointly produce a voltage response to a single absorbed photon via successive formation of a photon-induced and a current-induced normal hotspot in a narrow superconducting strip. The response time of the detector should increase with the photon energy providing energy resolution. Depending on the superconducting material and operation conditions, the cut-off wavelength for the single-photon detection regime varies from infrared waves to visible light. We simulated the performance of the background-limited infrared direct detector and X-ray photon counter utilizing the above mechanism. Low dark count rate and intrinsic low-frequency cut-off allow for realizing a background limited noise equivalent power of 10−20 W Hz−1/2 for a far-infrared direct detector exposed to 4-K background radiation. At low temperatures, the intrinsic response time of the counter is rather determined by diffusion of nonequilibrium electrons than by the rate of energy transfer to phonons. Therefore, thermal fluctuations do not hamper energy resolution of the X-ray photon counter that should be better than 10−3 for 6-keV photons. Comparison of new data obtained with a Nb based detector and previously reported results on NbN quantum detectors support our estimates of ultimate detector performance. | ||||
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ISSN | 1286-0042 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 534 | |||
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Author | Saveskul, N. A.; Titova, N. A.; Baeva, E. M.; Semenov, A. V.; Lubenchenko, A. V.; Saha, S.; Reddy, H.; Bogdanov, S. I.; Marinero, E. E.; Shalaev, V. M.; Boltasseva, A.; Khrapai, V. S.; Kardakova, A. I.; Goltsman, G. N. | ||||
Title | Superconductivity behavior in epitaxial TiN films points to surface magnetic disorder | Type | Journal Article | ||
Year | 2019 | Publication | Phys. Rev. Applied | Abbreviated Journal | Phys. Rev. Applied |
Volume | 12 | Issue | 5 | Pages | 054001 |
Keywords | epitaxial TiN films | ||||
Abstract | We analyze the evolution of the normal and superconducting properties of epitaxial TiN films, characterized by high Ioffe-Regel parameter values, as a function of the film thickness. As the film thickness decreases, we observe an increase of the residual resistivity, that becomes dominated by diffusive surface scattering for d≤20nm. At the same time, a substantial thickness-dependent reduction of the superconducting critical temperature is observed compared to the bulk TiN value. In such high-quality material films, this effect can be explained by a weak magnetic disorder residing in the surface layer with a characteristic magnetic defect density of approximately 1012cm−2. Our results suggest that surface magnetic disorder is generally present in oxidized TiN films. | ||||
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ISSN | 2331-7019 | ISBN | Medium | ||
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Notes | Approved | no | |||
Call Number | Serial | 1166 | |||
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Author | Neroev, V. V.; Iomdina, E. N.; Khandzhyan, A. T.; Khodzhabekyan, N. V.; Sengaeva, M. D.; Ivanova, A. V.; Seliverstov, S. V.; Teplyakova, K. O.; Goltsman, G. N. | ||||
Title | Experimental study of the effect of corneal hydration and its biomechanical properties on the results of photorefractive keratectomy | Type | Journal Article | ||
Year | 2021 | Publication | Vestn. Oftalmol. | Abbreviated Journal | Vestn. Oftalmol. |
Volume | 137 | Issue | 3 | Pages | 68-75 |
Keywords | THz scanning, cornea, photorefractive keratectomy, medicine | ||||
Abstract | Water content in the cornea may affect the outcome of its excimer laser ablation, especially in presbyopic patients with myopic refraction. This hypothesis can be tested by scanning the cornea in the terahertz (THz) range to determine its hydration level. Purpose: To study the effect of hydration of the cornea determined by non-contact THz scanning and its biomechanical parameters on the results of photorefractive keratectomy (PRK) in an experiment. Material and methods: PRK was performed using the Nidek EC-5000 QUEST excimer laser on 8 rabbit eyes. Corneal hydration was evaluated by determining the reflection coefficient (RC) in the THz electromagnetic radiation range before PRK, after 3-5 days, and after 1, 2, 3, and 4 months. Clinical examination included autorefractometry, assessment of corneal thickness and other anatomical and optical parameters of the anterior eye segment (Galilei G6, Ziemer Ophthalmic Systems AG 6.0.2, Switzerland), measurement of corneal hysteresis (CH) and corneal resistance factor (CRF) using the Ocular Response Analyzer (ORA; Reichert, USA), as well as tear production (Schirmer test). Results: The initial water content in the cornea has a significant effect on the thickness of the removed layer, i.e. on the PRK effect, with correlation coefficient of Rs= -0.976 (p<0.01). The correlation between CH and the ablation depth is less pronounced (Rs=0.643), and CRF had no correlation with it (Rs= -0.089). Biomechanical indicators of the cornea depend on its hydration: changes in CH and CRF after excimer laser ablation qualitatively coincide with changes in RC, the correlation coefficient between RC and the initial value of CH is R= -0.619 (moderate negative correlation). Conclusion: THz scanning is an effective non-contact technology for monitoring corneal hydration level. The mismatch of the hypoeffect of keratorefractive excimer laser intervention planned for patients with presbyopia with the actual outcome can be caused by individual decrease in the initial water content in the cornea. |
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Language | Russian | Summary Language | Original Title | ||
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Notes | Approved | no | |||
Call Number | Serial | 1794 | |||
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Author | Semenov, A. D.; Heusinger, M. A.; Renk, K. F.; Menschikov, E.; Sergeev, A. V.; Elant'ev, A. I.; Goghidze, I. G.; Gol'tsman, G. N. | ||||
Title | Influence of phonon trapping on the performance of NbN kinetic inductance detectors | Type | Journal Article | ||
Year | 1997 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
Volume | 7 | Issue | 2 | Pages | 3083-3086 |
Keywords | NbN KID | ||||
Abstract | Voltage and microwave photoresponse of NbN thin films to modulated and pulsed optical radiation reveals, far below the superconducting transition, a response time consistent with the lifetime of nonequilibrium quasiparticles. We show that even in 5 nm thick films at 4.2 K the phonon trapping is significant resulting in a quasiparticle lifetime of a few nanoseconds that is an order of magnitude larger than the recombination time. Values and temperature dependence of the quasiparticle lifetime obey the Bardeen-Cooper-Schrieffer theory and are in quantitative agreement with the electron-phonon relaxation rate determined from the resistive response near the superconducting transition. We discuss a positive effect of the phonon trapping on the performance of kinetic inductance detectors. | ||||
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ISSN | 1051-8223 | ISBN | Medium | ||
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Notes | Approved | no | |||
Call Number | Serial | 1598 | |||
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Author | Fedorov, G. E.; Stepanova, T. S.; Gazaliev, A. S.; Gaiduchenko, I. A.; Kaurova, N. S.; Voronov, B. M.; Goltzman, G. N. | ||||
Title | Asymmetric devices based on carbon nanotubes for terahertz-range radiation detection | Type | Journal Article | ||
Year | 2016 | Publication | Semicond. | Abbreviated Journal | Semicond. |
Volume | 50 | Issue | 12 | Pages | 1600-1603 |
Keywords | carbon nanotubes, CNT detectors | ||||
Abstract | Various asymmetric detecting devices based on carbon nanotubes (CNTs) are studied. The asymmetry is understood as inhomogeneous properties along the conducting channel. In the first type of devices, an inhomogeneous morphology of the CNT grid is used. In the second type of devices, metals with highly varying work functions are used as the contact material. The relation between the sensitivity and detector configuration is analyzed. Based on the data obtained, approaches to the development of an efficient detector of terahertz radiation, based on carbon nanotubes are proposed. | ||||
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ISSN | 1063-7826 | ISBN | Medium | ||
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Notes | Approved | no | |||
Call Number | Serial | 1776 | |||
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Author | Galin, M. A.; Klushin, A. M.; Kurin, V. V.; Seliverstov, S. V.; Finkel, M. I.; Goltsman, G. N.; Müller, F.; Scheller, T.; Semenov, A. D. | ||||
Title | Towards local oscillators based on arrays of niobium Josephson junctions | Type | Journal Article | ||
Year | 2015 | Publication | Supercond. Sci. Technol. | Abbreviated Journal | Supercond. Sci. Technol. |
Volume | 28 | Issue | 5 | Pages | 055002 (1 to 7) |
Keywords | Josephson junction local oscillators, JJ LO | ||||
Abstract | Various applications in the field of terahertz technology are in urgent need of compact, wide-tunable solid-state continuous wave radiation sources with a moderate power. However, satisfactory solutions for the THz frequency range are scarce yet. Here we report on coherent radiation from a large planar array of Josephson junctions (JJs) in the frequency range between 0.1 and 0.3 THz. The external resonator providing the synchronization of JJ array is identified as a straight fragment of a single-strip-line containing the junctions themselves. We demonstrate a prototype of the quasioptical heterodyne receiver with the JJ array as a local oscillator and a hot-electron bolometer mixer. | ||||
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ISSN | 0953-2048 | ISBN | Medium | ||
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Notes | Approved | no | |||
Call Number | Serial | 1347 | |||
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Author | Yang, Y.; Fedorov, G.; Shafranjuk, S. E.; Klapwijk, T. M.; Cooper, B. K.; Lewis, R. M.; Lobb, C. J.; Barbara, P. | ||||
Title | Electronic transport and possible superconductivity at Van Hove singularities in carbon nanotubes | Type | Journal Article | ||
Year | 2015 | Publication | Nano Lett. | Abbreviated Journal | Nano Lett. |
Volume | 15 | Issue | 12 | Pages | 7859-7866 |
Keywords | carbon nanotubes, CNT, tunable superconductivity, van Hove singularities | ||||
Abstract | Van Hove singularities (VHSs) are a hallmark of reduced dimensionality, leading to a divergent density of states in one and two dimensions and predictions of new electronic properties when the Fermi energy is close to these divergences. In carbon nanotubes, VHSs mark the onset of new subbands. They are elusive in standard electronic transport characterization measurements because they do not typically appear as notable features and therefore their effect on the nanotube conductance is largely unexplored. Here we report conductance measurements of carbon nanotubes where VHSs are clearly revealed by interference patterns of the electronic wave functions, showing both a sharp increase of quantum capacitance, and a sharp reduction of energy level spacing, consistent with an upsurge of density of states. At VHSs, we also measure an anomalous increase of conductance below a temperature of about 30 K. We argue that this transport feature is consistent with the formation of Cooper pairs in the nanotube. | ||||
Address | Department of Physics, Georgetown University , Washington, District of Columbia 20057, United States | ||||
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ISSN | 1530-6984 | ISBN | Medium | ||
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Notes | PMID:26506109; Suuplementary info (attached to pdf) DOI: 10.1021/acs.nanolett.5b02564 | Approved | no | ||
Call Number | Serial | 1782 | |||
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