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Information × Registration Number 0221U101902, 0118U002037 , R & D reports Title Theoretical and experimental investigations of the principles of the operation of quantum meters of single X-ray photons on the basis of high-temperature superconductors. popup.stage_title Head Shklovskyi Valerii O, Registration Date 26-01-2021 Organization V.N. Karazin Kharkiv National University popup.description2  The object of the study is films and thin single crystals of layered high-temperature superconductors, the anisotropy and nonlinearity specific for them are characteristic of the resistive response of superconducting films in the mixed state in the presence of point and planar potentials. The subject of the study is the anisotropic and nonlinear current dynamics of superconducting condensate and vortex ensemble in films and thin single crystals of layered high-temperature superconductors. A non-threshold electromagnetic radiation detector, which is a current-carrying superconducting film with a normal domain was analyzed. The normal domain is formed as a result of heating a portion of the film by an external heat source, and Joule heat in the domain. The detection mechanism consists in the fact that the heating of the film by electromagnetic radiation leads to an increase in the length of the normal domain, and thereby to an increase in voltage across the film. It was calculated the sensitivity of the detector under consideration, and determined the conditions under which this sensitivity reaches its maximum. Almost any use of a superconductor implies a non-equilibrium state. Remarkably, while a sufficiently high-power electromagnetic field of GHz frequency can stimulate superconductivity, fast motion of magnetic flux quanta (Abrikosov vortices) can trigger an instability abruptly quenching the superconducting state. show that such dynamical quenching of the vortex state in Nb thin films can be advanced or delayed by tuning the power and frequency of the microwave ac stimulus added to a dc bias current. The experimental findings are supported by time-dependent Ginzburg-Landau simulations and they can be explained, qualitatively, based on a model of “breathing mobile hot spots”, implying a competition of heating and cooling of quasiparticles along the trajectories of moving fluxons whose core sizes vary in time. In addition, we demonstrate universality of the stim Product Description popup.authors Beletsky Vladimir I Beletsky Vladimir I Beletsky Vladimir I Bezuglyj Olexei I Bezuglyj Olexei I Bezuglyj Olexei I Khadzhai Georgy Ya. Khadzhai Georgy Ya. Khadzhai Georgy Ya. popup.nrat_date 2021-01-26 Close