Theory of Scanning Tunneling Microscopy Probe of Impurity States in a D-Wave Superconductor

TL;DR

This paper explores how scanning tunneling microscopy can be used to investigate impurity states and the order-parameter symmetry in high-temperature d-wave superconductors, providing detailed insights into their quasiparticle behavior.

Contribution

It introduces a theoretical framework for using STM to analyze impurity-induced quasiparticle states and the superconducting order parameter symmetry in d-wave superconductors.

Findings

Local density of states is sensitive to impurity resonances.

Impurity states reveal information about the order parameter symmetry.

STM can distinguish different impurity-induced quasiparticle features.

Abstract

Scanning tunneling microscopy can provide a probe for the detailed study of quasiparticle states in high-Tc superconductors. We propose that it can also be used to acquire specific information about impurity-induced quasiparticle states and the superconducting order-parameter structure. In particular, the local density of states is found to be sensitive to impurity-induced resonances and to the symmetry of the order parameter.