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High pressure-high temperature electrical resistivity study on composition-controlled Nd_0.9Ca_0.1Ba₂Cu₃O_7-δ high T_c superconductor (HTSC) is carried out by a four-probe technique using Bridgman anvils. A simple heating coil arrangement is used for heating the samples. Electrical resistivity behavior under pressure (up to a maximum of 8 GPa) at various temperatures (up to a maximum of 523 K) were studied and reported in this paper. Simulation of energy dispersive X-ray diffraction confirms substitution of calcium at the Nd site of Nd-123. Variation of the electrical resistivity under pressure is compared with that of the structural changes and the bulk modulus was determined.

High pressure electrical resistivity studies were carried out on the high temperature superconductor Nd_1-xCa_xBa₂Cu₃O_7-δ for various calcium concentrations x=0.00, 0.03, 0.06 and 0.10 obtained by the solid-state reaction method. The electrical resistivity study was performed using the four-probe technique with a Bridgman opposed anvil device. All four samples show an initial drastic fall in electrical resistivity up to a pressure of around 3 GPa that remains almost constant up to 8 GPa.