The density of states and the low temperature specific heat of higb-Tc superconductors are calculated in a functional integral formalism using the slave boson technique. The manybody calculation in a saddle point approximation shows that the Iow energy sector is dominated by 3 single band. The calculated values of density of states are in good agreement with experimental results.
S. V. Vettoor and Dr. V . M. Nandakumaran, “Density of states in high - Tc superconductors”, Physica C: Superconductivity, vol. 191, pp. 277–281, 1992.