Revisiting heat capacity of bulk polycrystalline YBa2Cu3O7-{\delta}

Abstract

In this letter, we present the superconducting property characterization of a phase pure reasonably good quality YBa2Cu3O7-{\delta} sample. Studied compound is crystallized in orthorhombic Pmmm space group with lattice parameters a, b, and c are 3.829(2) {\AA}, 3.887(1) {\AA} and 11.666(3) {\AA} respectively. Bulk superconductivity is observed below 90K as evidenced by resistivity and dc/ac magnetization measurements. The resistivity under magnetic field ({\rho}TH) measurements showed clearly both the intra-grain and inter-grain transitions, which are supplemented by detailed (varying frequency and amplitude) ac susceptibility studies as well. The upper critical field at 0K i.e., Hc2(0) being determined from {\rho}TH measurements with 50% criteria of resistivity drope is ~ 70 Tesla. Studied polycrystalline YBa2Cu3O7-{\delta} is subjected to detailed heat capacity (CP) studies. Cp exhibited well defined anomaly at below 90 K, which decreases with applied field. Though the Cp anomaly/peak at Tc reduces with applied field, the same is not completely suppressed in high applied fields of up to 12 Tesla. The Sommerfeld constant ({\gamma}) and Debye temperature ({\Theta}D) as determined from low temperature fitting of CP(T) data to Sommerfeld-Debye model, are 10.65 mJ/mole-K2 and 312.3 K respectively. The results are compared with existing literature on bulk polycrystalline superconducting YBa2Cu3O7-{\delta} sample