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Quasiparticle properties around a nonmagnetic impurity in the superconducting state of the two-dimensional t-J model

Hiroki Tsuchiura·Yukio Tanaka·Masao Ogata·Satoshi Kashiwaya
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Abstract

The superconducting state around a well isolated nonmagnetic impurity in the high-Tc 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 zero-energy peak is not found. The zero-energy states corresponding to the zero-energy peak is approximately localized around the impurity.

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Hiroki Tsuchiura, Yukio Tanaka, Masao Ogata, Satoshi Kashiwaya. 1999-07-21. Quasiparticle properties around a nonmagnetic impurity in the superconducting state of the two-dimensional t-J model. https://doi.org/10.1143/jpsj.68.2510

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