Non-magnetic tight binding disorder effects in the $\gamma$ sheet of $Sr_2RuO_4$

TL;DR

This paper investigates how non-magnetic disorder affects the electronic properties of the b3 sheet in Sr2RuO4 using numerical simulations of an anisotropic tight-binding model, exploring different scattering regimes and disorder concentrations.

Contribution

It provides a numerical analysis of disorder effects in the b3 sheet of Sr2RuO4, focusing on the behavior of the tiny superconducting gap predicted by the Miyake-Narikiyo model.

Findings

Unitary and intermediate scattering limits are maintained across various disorder levels.

Disorder influences the tiny superconducting gap in the b3 sheet.

Numerical results support the persistence of certain scattering regimes despite disorder.

Abstract

Inspired by the physics of the Miyake - Narikiyo model (MN) for superconductivity in the {\gamma} sheet of $Sr_2RuO_4$ to investigate numerically the behavior caused by a non-magnetic disorder in the imaginary part of the elastic scattering matrix for an anisotropic tight-binding model. We perform simulations by going from the Unitary to the Born scattering limit, varying the parameter c which is inverse to the strength of the impurity potential. It is found that the unitary and intermedia limits persist for different orders of magnitude in simulating the disorder concentration. Subsequently and in order to find the MN tiny gap, we perform a numerical study of the unitary limit as a function of disorder concentration, to find the tiny anomalous gap.