Dependences of Hall coefficient and superconducting transition temperature on oxygen-content and pressure in Y0.9Ca0.1Ba2Cu3Oy

Abstract Hall coefficient R H and superconducting transition temperature T c in Y 0.9 Ca 0.1 Ba 2 Cu 3 O y with 6.59≤y≤7.01 have been measured under ambient pressure and under high pressure up to 2GPa. It is found that the relation of T c and Hall number 1/eR H under high pressure is explained in terms of the change in the carrier density and the pressure-induced pairing effect which depends on the oxygen-content.