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Information × Registration Number 0212U005168, 0107U000942 , R & D reports Title Quantum coherent fenomena in superconducting and mesoscopic structures popup.stage_title Head Omelyanchouk Alexander Nikolayevich, Registration Date 28-03-2012 Organization B.Verkin Institute for Low Temperature Physics and Engineering of National Academy of Science of Ukraine popup.description2 During executing the research issue, the following major fundamental and applied results are obtained: The theory is built of non-linear and parametric phenomena in Josephson flux qubit, a promising element of quantum computers. The existence of an analog of quantum Ruby oscillations in classic regime of a qubit is revealed. The new phenomena are predicted which are noise-induced quantum coherence and undamped Ruby oscillations. Noise spectroscopy of multi-qubit system is proposed for the first time. The theory of multi-particle currents in superconducting tunnel junction accounting for quasiparticle energy relaxation in the junction banks and the theory of vortex states in Josephson tunnel junction of arbitrary size in presence of external parallel magnetic field and transport current are built. In newly designed and manufactured qubits, single-photon Ruby oscillations in magnetic susceptibility spectrum of the charge-flux qubit coupled to low-frequency resonance tank were observed using weak continuous measurement technique. Cryogenic and measuring equipment is designed to study superconductor areas with locally frozen magnetic field. The current in the branches of a double-connected superconductor was found to exhibit continuous quasi-harmonic oscillations when dc transport current through the superconductor reached the critical value in one of its branches. Non-monotonic temperature dependence of magnetization of high-Tc single crystal superconductors with optimal doping is found that confirms the conclusion about Josephson behavior of twin boundaries. By laser microscopy method, the spatial structure of resistive state of two-zone superconductor MgB2 was examined and characteristic behavior of MgB2 compound caused by existence of two superconducting gaps was revealed. The principle and the circuitry of completely superconducting stochastic-resonance amplifier are proposed, its sensitivity and the back action to a quantum system-under-test are estimated. The possibility of creation of bolometric many-element HTSC transducer of an IR image with one-by-one information readout by a laser probe is theoretically and experimentally justified. The results obtained by SQUID magnetometry can be utilized practically in designing ultrasensitive superconducting receivers. Product Description popup.authors Безуглий Євген Васильович Бондаренко Станіслав Іванович Гогадзе Гурамі Олександрович Журавель Олександр Петрович Куплевахський Сергій Вікторович Сиваков Олександр Георгійович Тимофєєв Валерій Петрович Шабло Анатолій Олександрович Шнирков Володимир Іванович Шустакова Галіна Володимирівна popup.nrat_date 2020-04-02 Close