고온초전도체 Y₁Ba₂Cu₃O7-y 의 자기이방성

다국어 초록 (Multilingual Abstract)

Magnetic properties of grain aligned high Tc Y₁Ba₂Cu₃O_(7-y) superconductor are inverstigated. Grain-aligned superconductors have magnetic anisotropy in the Cu-O layer like single crystals. The lower critical field H_(c1). measured at the temperature range of 2 K up to 77 K, is found to be decreasing linearly as temperature goes up. Moreover, it decreaes more rapidly when the Cu-O layer is perpendicular to the external magnetic field. The temperature dependence of the magnetic susceptibility shows that the value of magnetic susceptibility, 4n X, is close to -1 at low temperature. The intra grain critical current density Jc, obtained from the Bean's critical state model, is found to be comparable to that of single crystal superconductors.