Influence of chemical pressure effects on nonlinear thermal conductivity of intrinsically granular superconductors

TL;DR

This paper models how chemical pressure influences the nonlinear thermal conductivity in granular superconductors, predicting significant enhancement under specific field conditions, with potential for experimental observation.

Contribution

It introduces a 2D Josephson junction array model to analyze chemical pressure effects on NLTC in granular superconductors, highlighting a novel enhancement mechanism.

Findings

NLTC can be substantially enhanced when chemoelectric and thermoelectric fields match.

The model parameters are realistic for experimental verification.

Chemical pressure effects are significant in non-stoichiometric superconductors.

Abstract

Using a 2D model of capacitively coupled Josephson junction arrays (created by a network of twin boundary dislocations with strain fields acting as an insulating barrier between hole-rich domains in underdoped crystals), we study the influence of chemical pressure on nonlinear thermal conductivity (NLTC) of an intrinsically granular superconductor. Quite a substantial enhancement of NLTC is predicted when intrinsic chemoelectric field closely matches the externally produced thermoelectric field. The estimates of the model parameters suggest a realistic possibility to experimentally monitor this effect in non-stoichiometric superconductors.