Theoretical Study on the Pressure Induced T-c Change in YBa2Cu3Ox

Pressure effect on the critical temperature, T-c, of the YBa2Cu3Ox superconductor was considered in the frame of a simple theoretical model which as a starting point assumes that T-c vs. pressure, P, dependence can be described by an inverted parabola. Available experimental results on T-c behavior under pressure were analyzed as a function of the zero pressure hole concentration in the superconducting CuO2 planes, n(h)(P = 0 GPa)= n(h0), for different constant values of P. Maximum T-c that can be achieved under pressure was estimated and discussed in relation to the n(h0) = 1/8 doping and establishment of charge and spin order. The results obtained here were used to estimate increase of the hole concentration in the CuO2 planes which occurs as a result of pressure induced oxygen reordering