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Author | Polyakova, O. N.; Tikhonov, V. V.; Dzardanov, A. L.; Boyarskii, D. A.; Gol’tsman, G. N. | ||||
Title | Dielectric characteristics of ore minerals in a 10–40 GHz frequency range | Type | Journal Article | ||
Year | 2008 | Publication | Tech. Phys. Lett. | Abbreviated Journal | Tech. Phys. Lett. |
Volume | 34 | Issue | 11 | Pages | 967-970 |
Keywords | ore minerals, complex permittivity, sphalerite, magnetite, labradorite | ||||
Abstract | A new approach to investigation of the complex dielectric permittivity of both nonmetallic and ore minerals in the microwave frequency range is proposed. Using this approach, data on the complex permittivity of sphalerite, magnetite, and labradorite in a 10–40 GHz frequency range have been obtained for the first time. A method is proposed for calculating the complex permittivity from experimentally measured frequency dependences of the reflection and transmission coefficients of a plane-parallel plate of a given mineral. Approximate expressions that can be used for calculations of the complex refractive index and permittivity of minerals are presented. | ||||
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ISSN | 1063-7850 | ISBN | Medium | ||
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Notes | Approved | no | |||
Call Number | Serial | 1406 | |||
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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 | 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 | Jukna, A.; Kitaygorsky, J.; Pan, D.; Cross, A.; Perlman, A.; Komissarov, I.; Sobolewski, R.; Okunev, O.; Smirnov, K.; Korneev, A.; Chulkova, G.; Milostnaya, I.; Voronov, B.; Gol'tsman, G. | ||||
Title | Dynamics of hotspot formation in nanostructured superconducting stripes excited with single photons | Type | Journal Article | ||
Year | 2008 | Publication | Acta Physica Polonica A | Abbreviated Journal | Acta Physica Polonica A |
Volume | 113 | Issue | 3 | Pages | 955-958 |
Keywords | SSPD, SNSPD | ||||
Abstract | Dynamics of a resistive hotspot formation by near-infrared-wavelength single photons in nanowire-type superconducting NbN stripes was investigated. Numerical simulations of ultrafast thermalization of photon-excited nonequilibrium quasiparticles, their multiplication and out-diffusion from a site of the photon absorption demonstrate that 1.55 μm wavelength photons create in an ultrathin, two-dimensional superconducting film a resistive hotspot with the diameter which depends on the photon energy, and the nanowire temperature and biasing conditions. Our hotspot model indicates that under the subcritical current bias of the 2D stripe, the electric field penetrates the superconductor at the hotspot boundary, leading to suppression of the stripe superconducting properties and accelerated development of a voltage transient across the stripe. | ||||
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Notes | Approved | no | |||
Call Number | Serial | 1414 | |||
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Author | Chen, J.; Kang, L.; Jin, B. B.; Xu, W. W.; Wu, P. H.; Zhang, W.; Jiang, L.; Li, N.; Shi, S. C.; Gol'tsman, G. N. | ||||
Title | Properties of terahertz superconducting hot electron bolometer mixers | Type | Journal Article | ||
Year | 2008 | Publication | Int. J. Terahertz Sci. Technol. | Abbreviated Journal | Int. J. Terahertz Sci. Technol. |
Volume | 1 | Issue | 1 | Pages | 37-41 |
Keywords | NbN HEB mixers, noise temperature | ||||
Abstract | A quasi-optical superconducting niobium nitride (NbN) hot electron bolometer (HEB) mixer has been fabricated and measured in the terahertz (THz) frequency range of 0.5~2.52 THz. A receiver noise temperature of 2000 K at 2.52 THz has been obtained for the mixer without corrections. Also, the effect of a Parylene C anti-reflection (AR) coating on the silicon (Si) lens has been studied. | ||||
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Notes | Approved | no | |||
Call Number | Serial | 1417 | |||
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Author | Ejrnaes, M.; Cristiano, R.; Quaranta, O.; Pagano, S.; Gaggero, A.; Mattioli, F.; Leoni, R.; Voronov, B.; Gol’tsman, G. | ||||
Title | A cascade switching superconducting single photon detector | Type | Journal Article | ||
Year | 2007 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
Volume | 91 | Issue | 26 | Pages | 262509 (1 to 3) |
Keywords | SSPD, SNSPD, parallel-wire | ||||
Abstract | We have realized superconducting single photon detectors with reduced inductance and increased signal pulse amplitude. The detectors are based on a parallel connection of ultrathin NbN nanowires with a common bias inductance. When properly biased, an absorbed photon induces a cascade switch of all the parallel wires generating a signal pulse amplitude of 2mV. The parallel wire configuration lowers the detector inductance and reduces the response time well below 1ns. This work was performed in the framework of the EU project “SINPHONIA” NMP4-CT-2005-016433. |
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ISSN | 0003-6951 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1418 | |||
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Author | Bell, M.; Sergeev, A.; Mitin, V.; Bird, J.; Verevkin, A.; Gol’tsman, G. | ||||
Title | One-dimensional resistive states in quasi-two-dimensional superconductors: Experiment and theory | Type | Journal Article | ||
Year | 2007 | Publication | Phys. Rev. B | Abbreviated Journal | Phys. Rev. B |
Volume | 76 | Issue | 9 | Pages | 094521 (1 to 5) |
Keywords | uasi-two-dimensional superconductors, NbN | ||||
Abstract | We investigate competition between one- and two-dimensional topological excitations—phase slips and vortices—in the formation of resistive states in quasi-two-dimensional superconductors in a wide temperature range below the mean-field transition temperature TC0. The widths w=100nm of our ultrathin NbN samples are substantially larger than the Ginzburg-Landau coherence length ξ=4nm, and the fluctuation resistivity above TC0 has a two-dimensional character. However, our data show that the resistivity below TC0 is produced by one-dimensional excitations—thermally activated phase slip strips (PSSs) overlapping the sample cross section. We also determine the scaling phase diagram, which shows that even in wider samples the PSS contribution dominates over vortices in a substantial region of current and/or temperature variations. Measuring the resistivity within 7 orders of magnitude, we find that the quantum phase slips can only be essential below this level. | ||||
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Series Volume | Series Issue | Edition | |||
ISSN | 1098-0121 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1423 | |||
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Author | Gao, J. R.; Hajenius, M.; Tichelaar, F. D.; Klapwijk, T. M.; Voronov, B.; Grishin, E.; Gol’tsman, G.; Zorman, C. A.; Mehregany, M. | ||||
Title | Monocrystalline NbN nanofilms on a 3C-SiC∕Si substrate | Type | Journal Article | ||
Year | 2007 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
Volume | 91 | Issue | 6 | Pages | 062504 (1 to 3) |
Keywords | NbN films, nanofilms | ||||
Abstract | The authors have realized NbN (100) nanofilms on a 3C-SiC (100)/Si(100) substrate by dc reactive magnetron sputtering at 800°C. High-resolution transmission electron microscopy (HRTEM) is used to characterize the films, showing a monocrystalline structure and confirming epitaxial growth on the 3C-SiC layer. A film ranging in thickness from 3.4to4.1nm shows a superconducting transition temperature of 11.8K, which is the highest reported for NbN films of comparable thickness. The NbN nano-films on 3C-SiC offer a promising alternative to improve terahertz detectors. For comparison, NbN nanofilms grown directly on Si substrates are also studied by HRTEM. The authors acknowledge S. V. Svetchnikov at National Centre for HRTEM at Delft, who prepared the specimens for HRTEM inspections. This work was supported by the EU through RadioNet and INTAS. |
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ISSN | 0003-6951 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1425 | |||
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Author | Ryabchun, S.; Tong, C.-Y. E.; Blundell, R.; Kimberk, R.; Gol'tsman, G. | ||||
Title | Study of the effect of microwave radiation on the operation of HEB mixers in the terahertz frequency range | Type | Journal Article | ||
Year | 2007 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
Volume | 17 | Issue | 2 | Pages | 391-394 |
Keywords | NbN HEB mixers | ||||
Abstract | We have investigated the effect of injecting microwave radiation, with a frequency much lower than that corresponding to the energy gap of the superconductor, on the performance of the hot-electron bolometer mixer incorporated into a THz heterodyne receiver. More specifically, we show that exposing the mixer to microwave radiation does not cause a significant rise of the receiver noise temperature and fall of the mixer conversion gain so long as the microwave power is a small fraction of local oscillator power. The injection of a small, but controlled amount of microwave power therefore enables active compensation of local oscillator power and coupling fluctuations which can significantly degrade the gain stability of hot electron bolometer mixer receivers. | ||||
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Series Volume | Series Issue | Edition | |||
ISSN | 1051-8223 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1427 | |||
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Author | Dauler, E. A.; Robinson, B. S.; Kerman, A. J.; Yang, J. K. W.; Rosfjord, E. K. M.; Anant, V.; Voronov, B.; Gol'tsman, G.; Berggren, K. K. | ||||
Title | Multi-element superconducting nanowire single-photon detector | Type | Journal Article | ||
Year | 2007 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
Volume | 17 | Issue | 2 | Pages | 279-284 |
Keywords | SSPD, SNSPD | ||||
Abstract | A multi-element superconducting nanowire single photon detector (MESNSPD) is presented that consists of multiple independently-biased superconducting nanowire single photon detector (SNSPD) elements that form a continuous active area. A two-element SNSPD has been fabricated and tested, showing no measurable crosstalk between the elements, sub-50-ps relative timing jitter, and four times the maximum counting rate of a single SNSPD with the same active area. The MESNSPD can have a larger active area and higher speed than a single-element SNSPD and the input optics can be designed so that the detector provides spatial, spectral or photon number resolution. | ||||
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ISSN | 1051-8223 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1428 | |||
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Author | Jiang, L.; Antipov, S. V.; Voronov, B. M.; Gol'tsman, G. N.; Zhang, W.; Li, N.; Lin, Z. H.; Yao, Q. J.; Miao, W.; Shi, S. C.; Svechnikov, S. I.; Vakhtomin, Y. B. | ||||
Title | Characterization of the performance of a quasi-optical NbN superconducting HEB mixer | Type | Journal Article | ||
Year | 2007 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
Volume | 17 | Issue | 2 | Pages | 395-398 |
Keywords | NbN HEB mixers, noise temperature | ||||
Abstract | In this paper we focus mainly on the investigation of the performance of a quasi-optical (planar log-spiral antenna) phonon-cooled NbN superconducting hot electron bolometer (HEB) mixer, which is cryogenically cooled by a close-cycled 4-K cryocooler, at 500 and 850 GHz frequency bands. The mixer's noise performance, stability of IF output power, and local oscillator (LO) power requirement are characterized for three NbN superconducting HEB devices of different sizes. The transmission characteristics of Mylar and Zitex films with incidence waves of an elliptical polarization are also examined by measuring the mixer's noise temperature. The lowest receiver noise temperatures (with no corrections) of 750 and 1100 K are measured at 500 and 850 GHz, respectively. Experimental results also demonstrate that the bigger the HEB device is, the higher the stability of IF output power becomes. | ||||
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ISSN | 1051-8223 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1429 | |||
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Author | Zhang, Wen; Li, Ning; Jiang, Ling; Miao, Wei; Lin, Zhen-Hui; Yao, Qi-Jun; Shi, Sheng-Cai; Chen, Jian; Wu, Pei-Heng; Svechnikov, S. I.; Vachtomin, Y. B.; Antipov, S. V.; Voronov, B. M.; Gol'tsman, G. N. | ||||
Title | Noise behaviour of a THz superconducting hot-electron bolometer mixer | Type | Journal Article | ||
Year | 2007 | Publication | Chinese Phys. Lett. | Abbreviated Journal | Chinese Phys. Lett. |
Volume | 24 | Issue | 6 | Pages | 1778-1781 |
Keywords | NbN HEB mixers | ||||
Abstract | A quasi-optical superconducting NbN hot-electron bolometer (HEB) mixer is measured in the frequency range of 0.5–2.5 THz for understanding of the frequency dependence of noise temperature of THz coherent detectors. It has been found that noise temperature increasing with frequency is mainly due to the coupling loss between the quasi-optical planar antenna and the superconducting HEB bridge when taking account of non-uniform distribution of high-frequency current. With the coupling loss corrected, the superconducting HEB mixer demonstrates a noise temperature nearly independent of frequency. | ||||
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ISSN | 0256-307X | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1430 | |||
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Author | Kerman, A. J.; Dauler, E. A.; Yang, J. K. W.; Rosfjord, K. M.; Anant, V.; Berggren, K. K.; Gol’tsman, G. N.; Voronov, B. M. | ||||
Title | Constriction-limited detection efficiency of superconducting nanowire single-photon detectors | Type | Journal Article | ||
Year | 2007 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
Volume | 90 | Issue | 10 | Pages | 101110 (1 to 3) |
Keywords | SSPD, SNSPD | ||||
Abstract | We investigate the source of the large variations in the observed detection efficiencies of superconducting nanowire single-photon detectors between many nominally identical devices. Through both electrical and optical measurements, we infer that these variations arise from “constrictions:” highly localized regions of the nanowires where the effective cross-sectional area for superconducting current is reduced. These constrictions limit the bias-current density to well below its critical value over the remainder of the wire, and thus prevent the detection efficiency from reaching the high values that occur in these devices when they are biased near the critical current density. This work is sponsored by the United States Air Force under Contract No. FA8721-05-C-0002. |
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ISSN | 0003-6951 | ISBN | Medium | ||
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Notes | Approved | no | |||
Call Number | Serial | 1433 | |||
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Author | Słysz, W.; Wegrzecki, M.; Bar, J.; Grabiec, P.; Górska, M.; Zwiller, V.; Latta, C.; Böhi, P.; Pearlman, A.J.; Cross, A.S.; Pan, D.; Kitaygorsky, J.; Komissarov, I.; Verevkin, A.; Milostnaya, I.; Korneev, A.; Minayeva, O.; Chulkova, G.; Smirnov, K.; Voronov, B.; Gol’tsman, G.N.; Sobolewski, R. | ||||
Title | Fibre-coupled, single photon detector based on NbN superconducting nanostructures for quantum communications | Type | Journal Article | ||
Year | 2007 | Publication | J. Modern Opt. | Abbreviated Journal | J. Modern Opt. |
Volume | 54 | Issue | 2-3 | Pages | 315-326 |
Keywords | NbN SSPD, SNSPD | ||||
Abstract | We present a novel, two-channel, single photon receiver based on two fibre-coupled, NbN, superconducting, single photon detectors (SSPDs). The SSPDs are nanostructured superconducting meanders and are known for ultrafast and efficient detection of visible-to-infrared photons. Coupling between the NbN detector and optical fibre was achieved using a micromechanical photoresist ring placed directly over the SSPD, holding the fibre in place. With this arrangement, we obtained coupling efficiencies up to ∼30%. Our experimental results showed that the best receiver had a near-infrared system quantum efficiency of 0.33% at 4.2 K. The quantum efficiency increased exponentially with the photon energy increase, reaching a few percent level for visible-light photons. The photoresponse pulses of our devices were limited by the meander high kinetic inductance and had the rise and fall times of approximately 250 ps and 5 ns, respectively. The receiver's timing jitter was in the 37 to 58 ps range, approximately 2 to 3 times larger than in our older free-space-coupled SSPDs. We stipulate that this timing jitter is in part due to optical fibre properties. Besides quantum communications, the two-detector arrangement should also find applications in quantum correlation experiments. | ||||
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Series Volume | Series Issue | Edition | |||
ISSN | 0950-0340 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1434 | |||
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Author | Baselmans, J. J. A.; Baryshev, A.; Reker, S. F.; Hajenius, M.; Gao, J. R.; Klapwijk, T. M.; Voronov, B.; Gol’tsman, G. | ||||
Title | Influence of the direct response on the heterodyne sensitivity of hot electron bolometer mixers | Type | Journal Article | ||
Year | 2006 | Publication | J. Appl. Phys. | Abbreviated Journal | J. Appl. Phys. |
Volume | 100 | Issue | 8 | Pages | 084510 (1 to 7) |
Keywords | NbN HEB mixers | ||||
Abstract | We present a detailed experimental study of the direct detection effect in a small volume (0.15μm×1μm×3.5nm) quasioptical NbN phonon cooled hot electron bolometer mixer at 673GHz. We find that the small signal noise temperature, relevant for an astronomical observation, is 20% lower than the noise temperature obtained using 300 and 77K calibration loads. In a separate set of experiments we show that the direct detection effect is caused by a combination of bias current reduction when switching from the 77 to the 300K load in combination with the bias current dependence of the receiver gain. The bias current dependence of the receiver gain is shown to be mainly caused by the current dependence of the mixer gain. |
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ISSN | 0021-8979 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1442 | |||
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