Quasiparticle Properties around a Nonmagnetic Impurity in the Superconducting State of the Two-Dimensional t-J Model

抄録

The superconducting state around a well-isolated nonmagnetic impurity in the high-T_c superconductors is studied using the two-dimensional t-J model. The spatial dependence of the order parameter and the local density of states are obtained from the numerical diagonalization of the Bogoliubov-de Gennes equation derived using the Gutzwiller approximation. We find a zero-energy peak in the local density of states around the impurity. Different from the previous results on a vortex or surfaces in the t-J model, the splitting of the zero-energy peak is not found. The zero-energy states corresponding to the zero-energy peak is approximately localized around the impurity.