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Gershenzon, E. M., Gol’tsman, G. N., Dzardanov, A. L., & Zorin, M. A. (1991). Ultrafast superconductive switch. IEEE Trans. Magn., 27(2), 2844–2846.
Abstract: The transition from superconductive to resistive state caused by infrared radiation and bias current pulses was investigated in order to minimize switching time tau and driving power W. Experimental results for Nb microstrips confirm the correctness of calculations based on the model of electron heating. For Nb switches, tau measured directly is 0.3-0.8 ns for radiation pulses and 1-3 ns for bias current pulses at T=4.2 K, while for YBaCuO switches at T=77 K it is expected to be several picoseconds. For an YBaCuO sample with the dimensions of 5*2*0.15 mu m/sup 2/, W was 10 mW, and it can be further reduced to the order of several microwatts by decreasing the volume of the sample.
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Gerecht, E., Musante, C. F., Zhuang, Y., Yngvesson, K. S., Gol’tsman, G. N., Voronov, B. M., et al. (1999). NbN hot electron bolometric mixerss—a new technology for low-noise THz receivers. IEEE Trans. Appl. Supercond., 47(12), 2519–2527.
Abstract: New advances in hot electron bolometer (HEB) mixers have recently resulted in record-low receiver noise temperatures at terahertz frequencies. We have developed quasi-optically coupled NbN HEB mixers and measured noise temperatures up to 2.24 THz, as described in this paper. We project the anticipated future performance of such receivers to have even lower noise temperature and local-oscillator power requirement as well as wider gain and noise bandwidths. We introduce a proposal for integrated focal plane arrays of HEB mixers that will further increase the detection speed of terahertz systems.
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Semenov, A. D., Goghidze, I. G., Gol’tsman, G. N., Sergeev, A. V., Aksaev, E. E., & Gershenzon, E. M. (1993). Non-equilibrium quasiparticle response to radiation and bolometric effect in YBaCuO films. IEEE Trans. Appl. Supercond., 3(1), 2132–2135.
Abstract: The voltage photoresponse of structured current biased YBCO films on different substrates to 20-ps laser pulses of 0.63- mu m and 1.54- mu m wavelengths and to continuously modulated radiation of 2-mm wavelength is measured to temperatures around Tc. Fast picosecond decay of the response to pulsed radiation is followed by slow exponential relaxation with a nanosecond characteristic time depending on the substrate material and film dimensions. The slow component does not depend on wavelength and is attributed to the bolometric effect, while the magnitude of the fast component associated with nonequilibrium response rises with wavelength. More than an order-of-magnitude increase of the nonequilibrium response is seen from near-infrared to millimeter-wave range. This dependence plausibly reflects the low efficiency of multiplication of photoexcited electrons in YBaCuO compared to conventional superconductors.
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Nebosis, R. S., Heusinger, M. A., Schatz, W., Renk, K. F., Gol’tsman, G. N., Karasik, B. S., et al. (1993). Ultrafast photoresponse of a structured YBa2Cu3O7-δ thin film to ultrashort FIR laser pulses. IEEE Trans. Appl. Supercond., 3(1), 2160–2162.
Abstract: The authors have investigated the photoinduced voltage response of a current-carrying structured YBa2Cu3O7-δ thin film to ultrashort far-infrared (FIR) laser pulses in the frequency range from 0.7 THz to 7 THz. The detector has shown an almost constant sensitivity of 1 mV/W and a noise equivalent power of less than 5*10/sup -7/ W/ square root Hz. The temperature dependence of the decay time of the detector signal was studied for temperatures around the transition temperature of the film ( approximately 80 K). For a detector temperature where dR/dT had its maximum, the authors observed bolometric signals with decay times of about 2 ns, and for lower temperatures they observed nonbolometric signals with decay times of approximately 120 ps; the duration of the nonbolometric signals was limited by the time resolution of the electronic registration equipment.
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Xu, Y., Zheng, X., Williams, C., Verevkin, A., Sobolewski, R., Chulkova, G., et al. (2001). Ultrafast superconducting hot-electron single-photon detector. In CLEO (345).
Abstract: Summary form only given. The current most-pressing need is to develop a practical, GHz-range counting single-photon detector, operational at either 1.3-/spl mu/m or 1.55-/spl mu/m radiation wavelength, for novel quantum communication and quantum cryptography systems. The presented solution of the problem is to use an ultrafast hot-electron photodetector, based on superconducting thin-film microstructures. This type of device is very promising, due to the macroscopic quantum nature of superconductors. Very fast response time and the small, (meV range) value of the superconducting energy gap characterize the superconductor, leading to the efficient avalanche process even for infrared photons.
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Rosfjord, K. M., Yang, J. K. W., Dauler, E. A., Anant, V., Berggren, K. K., Kerman, A. J., et al. (2006). Increased detection efficiencies of nanowire single-photon detectors by integration of an optical cavity and anti-reflection coating. In CLEO/QELS (JTuF2 (1 to 2)).
Abstract: We fabricate and test superconducting NbN-nanowire single-photon detectors with an integrated optical cavity and anti-reflection coating. We design the cavity and coating such as to maximize absorption in the NbN film of the detector.
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Svechnikov, S. I., Finkel, M. I., Maslennikov, S. N., Vachtomin, Y. B., Smirnov, K. V., Seleznev, V. A., et al. (2006). Superconducting hot electron bolometer mixer for middle IR range. In Proc. 16th Int. Crimean Microwave and Telecommunication Technology (Vol. 2, pp. 686–687).
Abstract: The developed directly lens coupled hot electron bolometer (HEB) mixer was based on 5 nm superconducting NbN deposited on GaAs substrate. The layout of the structure, including 30x20 mcm^2 active area coupled with a 50 Ohm coplanar line, was patterned by photolithography. The responsivity of the mixer was measured in a direct detection mode in the 25-64 THz frequency range. The noise performance of the mixer and the directivity of the receiver were investigated in a heterodyne mode. A 10.6 mum wavelength CW CO2 laser was utilized as a local oscillator.
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Vachtomin, Y. B., Antipov, S. V., Maslennikov, S. N., Smirnov, K. V., Polyakov, S. L., Zhang, W., et al. (2006). Quasioptical hot electron bolometer mixers based on thin NBN films for terahertz region. In Proc. 16th Int. Crimean Microwave and Telecommunication Technology (Vol. 2, pp. 688–689).
Abstract: Presented in this paper are the performances of HEB mixers based on 2-3.5 nm thick NbN films integrated with log-periodic spiral antenna. Double side-band receiver noise temperature values are 1300 K and 3100 K at 2.5 THz and at 3.8 THz, respectively. Mixer gain bandwidth is 5.2 GHz. Local oscillator power is 1-3 muW for mixers with different active area
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Gol’tsman, G. N. (1994). Terahertz technology in Russia. In 24th European Microwave Conf. (Vol. 1, pp. 113–121).
Abstract: The presentation consider the parameters and operating peculiarities of unique microwave generators of the terahertz range which have been created in Russia – the backward wave oscillators – as well as certain devices based on these generators, such as high resolution. spectrometers and time-resolving spectrometers with picosecond temporal resolution. Most resent BWO-based studies are illustrated by a project devoted to superconductive hot-electron. bolometers which are of great independent value for the terahertz technology as high-sensitive picosecond detectors and low noise broad-band mixers.
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Merkel, H. F., Yagoubov, P. A., Kroug, M., Khosropanah, P., Kollberg, E. L., Gol’tsman, G. N., et al. (1998). Noise temperature and absorbed LO power measurement methods for NbN phonon-cooled hot electron bolometric mixers at terahertz frequencies. In Proc. 28th European Microwave Conf. (Vol. 1, pp. 294–299).
Abstract: In this paper the absorbed LO power requirements and the noise performance of NbN based phonon-cooled hot electron bolometric (HEB) quasioptical mixers are investigated for RF frequencies in the 0.55-1.1 range The minimal measured DSB noise temperatures are about 500 K at 640 GHz, 600 K at 750 GHz, 850 K at 910 GHz and 1250 K at 1.1 THz. The increase in noise temperature at 1.1THz is attributed to water absorption. The absorbed LO power is measured using a calorimetric approach. The results are subsequently corrected for lattice heating. These values are compared to results of a novel one dimensional hot spot mixer models and to a more traditional isotherm method which tends to underestimate the absorbed LO power for small bias powers. Typically a LO power between 50nW and 100nW is needed to pump the device to the optimal operating point.
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Pentin, I. V., Smirnov, A. V., Ryabchun, S. A., Gol’tsman, G. N., Vaks, V. L., Pripolzin, S. I., et al. (2011). Heterodyne source of THz range based on semiconductor superlattice multiplier. In IRMMW-THz (pp. 1–2).
Abstract: We present the results of our studies of the possibility of developing a heterodyne receiver incorporating a hot-electron bolometer mixer as the detector and a semiconductor superlattice multiplier driven by a reference synthesizer as the local oscillator. We observe that such a local oscillator offers enough power in the terahertz range to pump the HEB into the operating state.
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Zhang, J., Pearlman, A., Slysz, W., Verevkin, A., Sobolewski, R., Wilsher, K., et al. (2003). A superconducting single-photon detector for CMOS IC probing. In Proc. 16-th LEOS (Vol. 2, pp. 602–603).
Abstract: In this paper, a novel, time-resolved, NbN-based, superconducting single-photon detector (SSPD) has been developed for probing CMOS integrated circuits (ICs) using photon emission timing analysis (PETA).
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Maslennikov, S. N., Morozov, D. V., Ozhegov, R. V., Smirnov, K. V., Okunev, O. V., & Gol’tsman, G. N. (2004). Imaging system for submillimeter wave range based on AlGaAs/GaAs hot electron bolometer mixers. In Proc. 5-th MSMW (Vol. 2, pp. 558–560).
Abstract: Electromagnetic radiation of the submillimeter (SMM) range is dispersed and absorbed significantly less than infrared (IR) radiation when passing through different objects. That is the reason for the development of an SMM imaging system. In this paper, we discuss the design of an SMM heterodyne imager, based on a matrix of AlGaAs/GaAs heterostructure hot electron bolometer mixers (HEB) with relatively high (about 77 K) operating temperature. The predicted double side band (DSB) noise temperature is about 1000 K and optimal local oscillator (LO) power is about 1 /spl mu/W for such mixers, which seems to be quite prospective for an SMM heterodyne imager.
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Gol’tsman, G. N., Smirnov, K., Kouminov, P., Voronov, B., Kaurova, N., Drakinsky, V., et al. (2003). Fabrication of nanostructured superconducting single-photon detectors. IEEE Trans. Appl. Supercond., 13(2), 192–195.
Abstract: Fabrication of NbN superconducting single-photon detectors, based on the hotspot effect is presented. The hotspot formation arises in an ultrathin and submicrometer-width superconductor stripe and, together with the supercurrent redistribution, leads to the resistive detector response upon absorption of a photon. The detector has a meander structure to maximally increase its active area and reach the highest detection efficiency. Main processing steps, leading to efficient devices, sensitive in 0.4-5 /spl mu/m wavelength range, are presented. The impact of various processing steps on the performance and operational parameters of our detectors is discussed.
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Blundell, R., Kawamura, J. H., Tong, C. E., Papa, D. C., Hunter, T. R., Gol’tsman, G. N., et al. (1998). A hot-electron bolometer mixer receiver for the 680-830 GHz frequency range. In Proc. 6-th Int. Conf. Terahertz Electron. (pp. 18–20). IEEE.
Abstract: We describe a heterodyne receiver designed to operate in the partially transparent atmospheric windows centered on 680 and 830 GHz. The receiver incorporates a niobium nitride thin film, cooled to 4.2 K, as the phonon-cooled hot-electron mixer element. The double sideband receiver noise, measured over the frequency range 680-830 GHz, is typically 700-1300 K. The instantaneous output bandwidth of the receiver is 600 MHz. This receiver has recently been used at the SubMillimeter Telescope, jointly operated by the Steward Observatory and the Max Planck Institute for Radioastronomy, for observations of the neutral carbon and CO spectral lines at 810 GHz and at 806 and 691 GHz respectively. Laboratory measurements on a second mixer in the same test receiver have yielded extended high frequency performance to 1 THz.
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