Vibronic Mechanism of the Isotope and Pressure Effects in Cuprates

TL;DR

This paper proposes a vibronic mechanism explaining how isotope substitution and pressure influence the superconducting transition temperature in cuprates, emphasizing the role of local bosons and Jahn-Teller centers.

Contribution

It introduces a detailed vibronic model that accounts for isotope and pressure effects on T_c in cuprates, extending understanding beyond percolation phenomena.

Findings

Vibronic interactions significantly affect isotope and pressure effects on T_c.

The model explains principal peculiarities of isotopic and baric effects in cuprates.

Percolation phenomena are not essential in the proposed mechanism.

Abstract

The doped cuprates are considered to be a system of local spinless bosons moving in a lattice of the hole pseudo-Jahn-Teller centers CuO_{4}^{5-}. A detailed qualitative and quantitative description of the vibronic mechanism determining both the isotope substitution and the external pressure effect on T_c is given. This mechanism can properly interpret the principal peculiarities of isotopic and baric effects in cuprates except the region of the well developed percolation phenomena