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Gol’tsman, G., Okunev, O., Chulkova, G., Lipatov, A., Dzardanov, A., Smirnov, K., et al. (2001). Fabrication and properties of an ultrafast NbN hot-electron single-photon detector. IEEE Trans. Appl. Supercond., 11(1), 574–577.
Abstract: A new type of ultra-high-speed single-photon counter for visible and near-infrared wavebands based on an ultrathin NbN hot-electron photodetector (HEP) has been developed. The detector consists of a very narrow superconducting stripe, biased close to its critical current. An incoming photon absorbed by the stripe produces a resistive hotspot and causes an increase in the film’s supercurrent density above the critical value, leading to temporary formation of a resistive barrier across the device and an easily measurable voltage pulse. Our NbN HEP is an ultrafast (estimated response time is 30 ps; registered time, due to apparatus limitations, is 150 ps), frequency unselective device with very large intrinsic gain and negligible dark counts. We have observed sequences of output pulses, interpreted as single-photon events for very weak laser beams with wavelengths ranging from 0.5 /spl mu/m to 2.1 /spl mu/m and the signal-to-noise ratio of about 30 dB.
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Gousev, Y. P., Gol'tsman, G. N., Karasik, B. S., Gershenzon, E. M., Semenov, A. D., Barowski, H. S., et al. (1996). Quasioptical superconducting hot electron bolometer for submillmeter waves. Int. J. of Infrared and Millimeter Waves, 17(2), 317–331.
Abstract: We report on a superconducting hot electron bolometer coupled to radiation via a broadband antenna. The bolometer, a structured NbN film, was patterned on a thin dielectric membrane between terminals of a gold slotline antenna. We investigated the response to submillimeter radiation (wave-lengths ∼ 0.1 mm to 0.7 mm) in the fundamental Gaussian mode. We found that the directivity of the antenna was constant within a factor of 2.5 through the whole experimental range. The noise equivalent power of the bolometer at 119 µm was ∼ 3 · 10−13 W/Hz1/2; a time constant of ∼ 160 ps was estimated.
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Gousev, Y. P., Semenov, A. D., Goghidze, I. G., Pechen, E. V., Varlashkin, A. V., Gol'tsman, G. N., et al. (1997). Current dependent noise in a YBa2Cu3O7-δ hot-electron bolometer. IEEE Trans. Appl. Supercond., 7(2), 3556–3559.
Abstract: We investigated the output noise of a YBa2Cu3O7-δ (YBCO) superconducting hot-electron bolometer (HEB) in a large frequency range (10 kHz to 8 GHz); the bolometer either consisted of a structured 50 nm thick YBCO film on LaAlO/sub 3/ or a 30 nm thick film on a MgO substrate. We found that flicker noise dominated at low frequencies (below 1 MHz), while at higher frequencies Johnson noise and a current dependent noise were the main noise sources.
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Gousev, Y. P., Semenov, A. D., Gol'tsman, G. N., Sergeev, A. V., & Gershenzon, E. M. (1994). Electron-phonon interaction in disordered NbN films. Phys. B Condens. Mat., 194-196, 1355–1356.
Abstract: Electron-phonon interaction time has been investigated in disordered films of NbN. A temperatures below 5.5 K tau_eph ~ T -1"6 which is attributed to the renormalisation of phonon spectrum in thin films.
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Gousev, Y. P., Gol'tsman, G. N., Semenov, A. D., Gershenzon, E. M., Nebosis, R. S., Heusinger, M. A., et al. (1994). Broadband ultrafast superconducting NbN detector for electromagnetic radiation. J. Appl. Phys., 75(7), 3695–3697.
Abstract: An ultrafast detector that is sensitive to radiation in a broad spectral range from submillimeter waves to visible light is reported. It consists of a structured NbN thin film cooled to a temperature below Tc (∼11 K). Using 20 ps pulses of a GaAs laser, we observed signal pulses with both rise and decay time of about 50 ps. From the analysis of a mixing experiment with submillimeter radiation we estimate an intrinsic response time of the detector of ∼12 ps. The sensitivity was found to be similar for the near‐infrared and submillimeter radiation. Broadband sensitivity and short response time are attributed to a quasiparticle heating effect.
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Gousev, Y. P., Semenov, A. D., Pechen, E. V., Varlashkin, A. V., Nebosis, R. S., & Renk K. F. (1996). Coupling of terahertz radiation to a high-Т(с) superconducting hot electron bolometer mixer. Appl. Phys. Lett.,, 69, 691–693.
Abstract: We report on efficient coupling of THz radiation to a high-T(c) superconducting hot electron bolometer that is suitable for heterodyne detection. Our quasioptical system consisted of a planar self-complementary spiral antenna on a dielectric substrate clamped to an extended hyperhemispherical lens. The antenna was integrated into a co-planar line for broadband intermediate frequency matching. Measurements in the homodyne regime at a frequency of 2.5 THz showed a radiation pattern with a beam width of 1° and a coupling efficiency of 0.1. We measured, at an intermediate frequency of 1.5 GHz, an output noise temperature of'160 K and estimated for the device, operated in the heterodyne regime, a system noise temperature of 30 000 K. We also discuss possibilities of significant improvement of the sensitivity.
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Henrich, D., Dorner, S., Hofherr, M., Il'in, K., Semenov, A., Heintze, E., et al. (2012). Broadening of hot-spot response spectrum of superconducting NbN nanowire single-photon detector with reduced nitrogen content. J. Appl. Phys., 112.
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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Heusinger, M. A., Nebosis, R. S., Schatz, W., Renk, K. F., Gol’tsman, G. N., Karasik, B. S., et al. (1993). Temperature dependence of bolometric and non-bolometric photoresponse of a structured YBa2Cu3O7-δ thin film. In M. Meissner, & R. O. Pohl (Eds.), Phonon Scattering in Condensed Matter VII. Springer Series in Solid-State Sciences (Vol. 112, pp. 193–195).
Abstract: We investigated the temperature dependence of the transient voltage photoresponse of a current biased structured YBa2Cu3O7−δ thin film in its transition temperature region, around 79 K. Both, picosecond nonbolometric and nanosecond bolometric response to ultrashort far-infrared laser pulses were found for frequencies between 25 cm−1 and 215 cm−1. We will discuss optimum conditions for radiation detection and present an analysis of the dynamical behaviour of excited high T c thin films.
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Hoogeveen, R. W. M., Yagoubov, P. A., Maurellis, A., Koshelets, V. P., Shitov, S. V., Mair, U., et al. (2003). New cryogenic heterodyne techniques applied in TELIS: the balloonborne THz and submillimeter limb sounder for atmospheric research. In M. Strojnik (Ed.), Proc. SPIE (Vol. 5152, pp. 347–355). SPIE.
Abstract: We present a design concept for a new state-of-the-art balloon borne atmospheric monitor that will allow enhanced limb sounding of the Earth’s atmosphere within the submillimeter and far-infrared wavelength spectral range: TELIS, TErahertz and submm LImb Sounder. The instrument is being developed by a consortium of major European institutes that includes the Space Research Organization of the Netherlands (SRON), the Rutherford Appleton Laboratory (RAL) will utilize state-of-the-art superconducting heterodyne technology and is designed to be a compact, lightweight instrument cpaable of providing broad spectral coverage, high spectral resolution and long flight duration ( 24 hours duration during a single flight campaign). The combination of high sensitivity and extensive flight duration will allow evaluation of the diurnal variation of key atmospheric constitutenets sucyh as OH, HO2, ClO, BrO togehter will onger lived constituents such as O3, HCL and N2O. Furthermore, TELIS will share a common balloon platform to that of the MIPAS-B Fourier Transform Spectrometer, developed by the Institute of Meteorology and Climate research of the over an extended spectral range. The combination of the TELIS and MIPAS instruments will provide atmospheric scientists with a very powerful observational tool. TELIS will serve as a testbed for new cryogenic heterodyne detection techniques, and as such it will act as a prelude to future spaceborne instruments planned by the European Space Agency (ESA).
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Hübers, H. W., Pavlov, S. G., Semenov, A. D., Tredicucci, A., Köhler, R., Mahler, L., et al. (2005). Investigation of a 2.5 THz quantum cascade laser as local oscillator. In Proc. 16th Int. Symp. Space Terahertz Technol. (18). Göteborg, Sweden.
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