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Information × Registration Number 0203U008017, 0100U003275 , R & D reports Title Transport properties of HTSC single crystals and compaunds which have phase transition of charge density waves type popup.stage_title Head Obolenskii M.A., Registration Date 10-04-2003 Organization Kharkov National University named after V.N.Karazin popup.description2 The subjects of investigations were single crystals of high temperature superconductors YBaCuO and quasi-two-dimensional compound Nb1-xSnxSe2. The main goal of present work was determination of influence both external factors (magnetic field, pressure) and point and plaine (twins boundaries) defects structure on superconducting transition and vortex dynamics in high temperature superconductor YBaCuO. Methods of investigations — analysis of electroresistive (CVC) and experimental data about magnetic susceptibility (isothermal magnetization). At conditions of artificial unidirectional twins structure it has been found experimentaly anisotropy of plastic creep and guided motion of vortices along c-axis induced by twins planes. Moution of single vortices at slow magnetic field gave way to moution of vortex bundles in mediate magnetic field, but at high magnetic field creep is controlled by moution of vortex lattice dislocations. The mechanismus for anisotropy of vortex creep are discussed. Isothermal global magnetic measurements reveal a jump in slope of increasing part of the virgin magnetization curves. The observed feature may be attributed to a recently proposed disorder-induced transition (or crossover) from relatively ordered vortex lattice to a highly disordered vortex solid. An exact mathematical description of the Meissner effect and of the vortex state in periodic thin-layer superconductor/insulator structures with an arbitrary number of idential junctions N-1 (N is the number of superconducting layers) in the presence of a static parallel external field H are presented. Results of investigations will be used at a later time for the derivation of superconducting state models of HTSC. Product Description popup.authors popup.nrat_date 2020-04-02 Close