Theoretical Study of Specific Heat, Density of States, Free Energy, and Critical Field of High Temperature Cuprate Superconductors Based on Intra and Interlayer Interactions

Abstract

The role of attractive interlayer and intralayer interactions in layered high Tc cuprate superconductors have been investigated using a one-band two layer tight binding Hamiltonian. Self-consistent equations for the superconducting order parameter (Δ) and critical temperature (Tc) are derived using double time Green’s functions and equation of motion method. The expression for excitonic type correlation (γc), specific heat, density of states, free energy, and critical field are obtained. The interlayer interactions play an important role in the enhancement of Tc in layered high Tc cuprates. The oxygen isotope effect is also analyzed. The agreement between theoretical and experimental results for the system YBa2−xLaxCu3O7 (0≤x≤0.5) is quite satisfactory.