两种氧化物超导体在高压下的行为

BEHAVIOR OF TWO OXIDE SUPERCONDUCTORS UNDER HIGH PRESSURE

本文对两个单相超导氧化物体系 NdBa_2Cu_3O、和(Bi,Pb)_2Sr_2Cu_3O_Y分别做了低温,常温和高温下的高压观察。发现超导转变温度均随压力的增加而提高;在两个体系中都观察到1.0GPa 附近正常态电阻的突增,它们都对应于T_C增加的变缓。对NdBa_2Cu_3O、所做的高压DTA显示,从高温四方相到超导正交相的转变为压力所提前,表明高压对超导相结构的稳定性产生有利影响。

The high-pressure observations at low. normal and high temperature have been performed on two single-phased superconducting oxides, NdBa2Cu3Ox and (Bi, Pb)2Sr2Ca2Cu3Oy, respectively. The superconducting transition temperatures were all raised with increasing pressure. It was noted that the normal state resistances increased abruptly (then down again) near 1.0 GPa in both of the superconductors corresponding to a gentle step of the increasing Tc. The high-pressure DTA for NdBa2Cu3Ox showed that the transition from high temperature tetragonal phase to superconducting orthogonal phase is advanced, which indicates that the high pressure is advantageous to the stability of the superconducting phase structure.