An approach for studying the influence of uniaxial strain (pressure) on the temperature of the Bose-Einstein condensation of intersite bipolarons: possible implementation for RBa$_2$Cu$_3$O$_{7-\delta}$ cuprates

TL;DR

This paper presents a universal theoretical approach to analyze how uniaxial strain affects the Bose-Einstein condensation temperature of intersite bipolarons, with implications for high-temperature cuprate superconductors.

Contribution

It introduces a model linking lattice ion arrangements to the strain dependence of Bose-Einstein condensation temperature in cuprates.

Findings

Strain derivatives of condensation temperature depend on ion lattice configuration.

Uniaxial pressure effects on $T_c$ can be positive or negative.

Theoretical results align with experimental data on cuprate superconductors.

Abstract

A universal approach is proposed to study the influence of strain (pressure) on the temperature of Bose-Einstein condensation of intersite bipolarons within the extended Holstein model. It is shown that uniaxial strain (pressure) derivatives of the temperature of such a Bose-Einstein condensation strongly depend on the arrangement of ions in the lattice. In particular, they may be positive or negative. A connection between the theoretically obtained results, along with the experimental data, on the influence of uniaxial pressure (strain) on $T_c$ of RBa$_2$Cu$_3$O$_{7-\delta}$ family cuprates is discussed.