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Study on nonmagnetic impurities in the superconducting state of two-dimensional t-J model

Hideki Tanaka·Kazuhiro Kuboki·Manfred Sigrist
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Abstract

We study the effect of nonmagnetic impurities in the superconducting state of the t-J model. The Bogoliubov de Gennes equation is derived using a slave-boson mean-field approximation, and we solve it numerically at T=0. The d_{x^2-y^2}-wave order parameter is suppressed near an impurity and its spatial variation induces the extended s-wave component. We also find the local charge density wave (CDW)-like feature due to the Friedel oscillations. This leads to the splitting of the expected zero-energy Andreev bound state. Therefore the system is unlikely introducing a localized state of other symmetry such as superconductivity with broken time reversal symmetry or antiferromagnetism.

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Hideki Tanaka, Kazuhiro Kuboki, Manfred Sigrist. 1998-04-07. Study on nonmagnetic impurities in the superconducting state of two-dimensional t-J model. https://doi.org/10.1142/s0217979298001435

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