Tretyakov IV, Anfertyev VA, Revin LS, Kaurova NS, Voronov BM, Vaks VL, et al. Sensitivity and resolution of a heterodyne receiver based on the NbN HEB mixer with a quantum-cascade laser as a local oscillator. Radiophys Quant Electron. 2018;60(12):988–92.
Abstract: We present the results of experimental studies of the basic characteristics and operation features of a terahertz heterodyne detector based on the superconducting NbN HEB mixer and a quantum cascade laser as a local oscillator operating at a frequency of 2.02 THz. The measured noise temperature of such a mixer amounted to 1500 K. The spectral resolution of the detector is determined by the width of the local-oscillator spectral line whose measured value does not exceed 1 MHz. The quantum-cascade laser could be linearly tuned with respect to frequency with the coefficient 7.2 MHz/mA within the limits of the current oscillation bandwidth.
|
Smirnov K, Korneev A, Minaeva O, Divochiy A, Tarkhov M, Ryabchun S, et al. Ultrathin NbN film superconducting single-photon detector array. In: J. Phys.: Conf. Ser. Vol 61.; 2007. p. 1081–5.
Abstract: We report on the fabrication process of the 2 × 2 superconducting single-photon detector (SSPD) array. The SSPD array is made from ultrathin NbN film and is operated at liquid helium temperatures. Each detector is a nanowire-based structure patterned by electron beam lithography process. The advances in fabrication technology allowed us to produce highly uniform strips and preserve superconducting properties of the unpatterned film. SSPD exhibit up to 30% quantum efficiency in near infrared and up to 1% at 5-μm wavelength. Due to 120 MHz counting rate and 18 ps jitter, the time-domain multiplexing read-out is proposed for large scale SSPD arrays. Single-pixel SSPD has already found a practical application in non-invasive testing of semiconductor very-large scale integrated circuits. The SSPD significantly outperformed traditional single-photon counting avalanche diodes.
|
Zhang J, Boiadjieva N, Chulkova G, Deslandes H, Gol'tsman GN, Korneev A, et al. Noninvasive CMOS circuit testing with NbN superconducting single-photon detectors. Electron Lett. 2003;39(14):1086–8.
Abstract: The 3.5 nm thick-film, meander-structured NbN superconducting single-photon detectors have been implemented in the CMOS circuit-testing system based on the detection of near-infrared photon emission from switching transistors and have significantly improved the performance of the system. Photon emissions from both p- and n-MOS transistors have been observed.
|
Voronov BM, Gershenzon EM, Gol'tsman GN, Gubkina TO, Semash VD. Superconductive properties of ultrathin NbN films on different substrates. Sverkhprovodimost': Fizika, Khimiya, Tekhnika. 1994;7(6):1097–102.
Abstract: A study was made on dependence of surface resistance, critical temperature and width of superconducting transition on application temperature and thickness of NbN films, which varied within the range of 3-10 nm. Plates of sapphire, fused and monocrystalline quartz, MgO, as well as Si and silicon oxide were used as substrates. NbN films with 160 μθ·cm specific resistance and 16.5 K (Tc) critical temperature were obtained on sapphire substrates. Intensive growth of ΔTc was noted for films, applied on fused quartz, with increase of precipitation temperature. This is explained by occurrence of high tensile stresses in NbN films, caused by sufficient difference of thermal coefficients of expansion of NbN and quartz.
|
Tret’yakov IV, Ryabchun SA, Kaurova NS, Larionov PA, Lobastova AA, Voronov BM, et al. Optimum absorbed heterodyne power for superconducting NbN hot-electron bolometer mixer. Tech Phys Lett. 2010;36(12):1103–5.
Abstract: Absorbed heterodyne power has been measured in a low-noise broadband hot-electron bolometer (HEB) mixer for the terahertz range, operating on the effect of electron heating in the resistive state of an ultrathin superconducting NbN film. It is established that the optimum absorbed heterodyne power for the HEB mixer operating at 2.5 THz is about 100 nW.
|
