Bell, M., Sergeev, A., Mitin, V., Bird, J., Verevkin, A., & Gol'tsman, G. (2007). One-dimensional resistive states in quasi-two-dimensional superconductors. arXiv:0709.0709v1 [cond-mat.supr-con], , 1–11.
Abstract: We investigate competition between one- and two-dimensional topological excitations – phase slips and vortices – in formation of resistive states in quasi-two-dimensional superconductors in a wide temperature range below the mean-field transition temperature T(C0). The widths w = 100 nm of our ultrathin NbN samples is substantially larger than the Ginzburg-Landau coherence length ξ = 4nm and the fluctuation resistivity above T(C0) has a two-dimensional character. However, our data shows that the resistivity below T(C0) 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/temperature variations. Measuring the resistivity within seven orders of magnitude, we find that the quantum phase slips can only be essential below this level.
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Shurakov, A., Tong, C. -yu E., Grimes, P., Blundell, R., & Golt'sman, G. (2015). A microwave reflection readout scheme for hot electron bolometric direct detector. IEEE Trans. THz Sci. Technol., 5, 81–84.
Abstract: In this paper, we propose and present data from a fast THz detector based on the repurpose of hot electron bolometer mixers (HEB) fabricated from superconducting NbN thinfilm. This detector is essentially a traditional NbN bolometer element that operates under the influence of a microwave pump. The in-jected microwave power serves the dual purpose of enhancing the detector sensitivity and reading out the impedance changes of the device in response to incidentTHz radiation. We have measured an optical Noise Equivalent Power of 4 pW/ Hz for our detector at a bath temperature of 4.2 K. The measurement frequency was 0.83 THz and the modulation frequency was 1.48 kHz. The readout
scheme is versatile and facilitates both high-speed operation as well as multi-pixel applications.
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Корнеева, Ю. П., Флоря, И. Н., Корнеев, А. А., & Гольцман, Г. Н. (2010). Cверхпроводящий однофотонный детектор для дальнего ИК диапазона длин волн. In Науч. сессия НИЯУ МИФИ (pp. 46–47).
Abstract: Мы представляем быстродействующий сверхпроводниковый однофотонный детектор (SSPD) для дальнего инфракрасного диапазона на основе ультратонкой монокристаллической пленки NbN толщиной 3 нм, состоящий из параллельных полосок. QE на длине волны 1,5.μм и 1,3 μм для предложенного SSPD практически одинаковы. SSPD показывает отклик длительностью 200 пс, что открывает путь к детекторам, обладающим скоростью счета свыше 1 ГГц.
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Gershenzon, E. M., Il'in, V. A., Litvak-Gorskaya, L. B., & Filonovich, S. R. (1979). Character of submillimeter photoconductivity in n-lnSb. Sov. Phys. JETP, 49(1), 121–128.
Abstract: A comprehensive investigation was made of the submillimeter photoconductivity of n -1nSb in the range of wavelengths L = 0.6-8 mm, magnetic fields H = 0-30 kOe, electric fields E = 0.01-0.5 V/cm, and temperatures T = 1.3-30 K. The kinetics of the photoconductivity processes as a function of T, E; and H is investigated. It is shown that impurity photoconductivity does exist for any degree of compensation of extremely purified n-InSb. Particular attention is paid to the hopping photoconductivity realized in strongly compensated n-1nSb (K > 0.8).
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Ptitsina N. G., Chulkova G. M., Il'in K. S., Sergeev A. V., Pochinkov F. S., & Gershenzon E. M. (1997). Superconductivity has been found in a number of new compounds between the non-superconducting transition elements and nonmetals such as Si, Ge, and Te. These findings have suggested possible criteria for superconductivity in both elements and compounds. Phys. Rev. B, 56(16).
Abstract: The temperature dependence of the resistance of films of Al, Be, and NbC with small values of the electron mean free path L=1.5– 10 nm has been measured at 4.2–300 K. The resistance of all the films contains a T^2 contribution that is proportional to the residual resistance; this contribution has been attributed to the interference between the elastic electron scattering and the electron-phonon scattering. Fitting the data to the theory of the electron-phonon-impurity interference „M. Yu. Reiser and A. V. Sergeev, Zh. Eksp. Teor. Fiz. 92, 224 ~1987! @Sov. Phys. JETP 65, 1291 ~1987!#…, we obtain constants of nteraction of the electrons with transverse phonons, and estimate the contribution of this interaction to the electron dephasing rate in thin films of Au, Al, Be, Nb, and NbC. Our estimates are in a good agreement with the experimental data on the inelastic electronphonon scattering in these films. This indicates that the interaction of electrons with transverse phonons controls the electron-phonon relaxation rate in thin-metal films over a broad temperature range.
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