Kuldeep Kholiya

Study of Superconductivity in Infinite U Extended Hubbard Model: Application to High Tc Cuprates Kuldeep Kholiya

The present work entitled "Study of Superconductivity in Infinite U Extended Hubbard Model" deals with the superconducting state in high ?Tc cuprates with in the frame work of extended Hubbard model using Hubbard projection as well as ortho ? Fermions approaches, applicable for U ? ? limit. The expressions for the superconducting order parameter and carrier concentration in these two formalism by considering the extended Hubbard model which includes inter-site attractive interaction and next ? nearest neighbour hopping parameters have been obtained. Further, we have pointed out that, at T=0 K the expression of superconducting order parameter obtained on the basis of these two formalism just become identical while the temperature dependence of superconducting order parameter in these two approaches is quite different. We have also performed numerical computation for superconducting order parameter as well as BCS ratio as a function of doping and inter- site interaction. Finally, we have compared our numerical results with that of existing experimental and theoretical results.