Strong correlations lead to protected low energy excitations in disordered d-wave superconductors

Arti Garg; Mohit Randeria; Nandini Trivedi

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Strong correlations lead to protected low energy excitations in disordered d-wave superconductors

Arti Garg·Mohit Randeria·Nandini Trivedi

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Abstract

We show that strong correlations play a vital role in protecting low energy excitations in disordered high temperature superconductors. The impurity-induced low-energy density of states (DOS) is greatly reduced in the strongly correlated superconductor compared to d-wave Bogoliubov-deGennes theory. The gapless nodal quasiparticles, and the resulting `V' in the low-energy DOS, are much more robust against disorder compared to the large-gap antinodal excitations. We discuss the relevance of our results to angle-resolved photoemission and scanning tunneling spectroscopy experiments.

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Arti Garg, Mohit Randeria, Nandini Trivedi. 2006-09-26. Strong correlations lead to protected low energy excitations in disordered d-wave superconductors. https://arxiv.org/abs/cond-mat/0609666

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