Nernst effect and Critical Field in Cuprate Superconductors

TL;DR

This paper presents calculations that align with recent experiments on the Nernst effect and critical fields in cuprate superconductors, suggesting disorder-induced local superconductivity as a key factor in high-temperature superconductivity.

Contribution

It introduces a model based on local BdG superconducting regions caused by disorder, offering an alternative to the pseudogap phase explanation.

Findings

Calculations agree with experimental Nernst and magnetization data.

Disorder-induced local superconductivity explains high critical temperatures.

Supports the significance of disorder in HTSC physics.

Abstract

A series of recent experiments on the Nernst effect, upper critical field $H_{c2}$ and enhanced diamagnetic magnetization $M$ by Wang et al (PRB 73, 024510), were interpreted as to provide evidence for the pseudogap scenario which long-range phase coherence is destroyed by thermally-created vortices. We present here calculations in good agreement with these measurements but based on the local formation of conventional Bogoliubov-deGennes (BdG) superconducting regions in doped disordered cuprate superconductors. Our results imply in an alternate scenario which the disorder plays a fundamental role in the high critical temperature superconductors (HTSC) physics.