Irreversible phenomena in the absorption of electromagnetic field in HTSC plates

Temperature dependence of the impedance in the 4.2 to 300 K range and hysteresis phenomena in the absorption with the field varying from – 70 to 70 kOe were studied in the M–Ba–Cu–O (M = Y, Yb, Eu, Gd) superconductor systems. Ceramic plates were studied in the frequency range from 5·104 to 2·107 Hz. Absorption hysteresis loops revealed a minimum at a field Hmin whose value grew with increasing external field oscillation amplitude and then saturated. A transformation of the hysteresis curve was observed near the superconducting transition. Peculiarities in absorption hysteresis phenomena are explained on the basis of a theory that accounts for the effect of Abrikosov vortices in Josephson junction banks on the critical current through it.

Перевод пока недоступен