Specific heat jump at Tc of high Tc superconductors: Effect of van hove singularity

Abstract

In the BCS framework, exact expressions for the ratio between the jump in the specific heat at Tc and the normal phase specific heat are derived within the Van Hove singularity scenario. Analytical results are obtained for an Isotropie s-wave and anisotropic rf-wave pairing symmetries. Graphical solutions of the ratio as functions of ωD/Tc and EF/Tc, where ωD is the cutoff energy and EF is the Fermi energy, show significant deviations from the BCS value of 1.43. ©2000 Plenum Publishing Corporation.