Spontaneous superconductivity and optical properties of high-Tc cuprates

TL;DR

This paper proposes a model where high-Tc superconductivity in cuprates arises from interlayer interactions mediated by in-plane plasmons, explaining various experimental observations without relying on specific in-plane mechanisms.

Contribution

The study introduces a model linking interlayer interactions via plasmons to superconductivity, accounting for Tc dependence on layer geometry and optical properties.

Findings

Model explains Tc dependence on interlayer distance.

Accounts for doping level mismatch and universal scaling relations.

Describes the role of c-axis geometry and optical properties in superconductivity.

Abstract

We suggest that the high temperature superconductivity in cuprate compounds may emerge due to interaction between copper-oxygen layers mediated by in-plane plasmons. The strength of the interaction is determined by the c-axis geometry and by the ab-plane optical properties. Without making reference to any particular in-plane mechanism of superconductivity, we show that the interlayer interaction favors spontaneous appearance of the superconductivity in the layers. At a qualitative level the model describes correctly the dependence of the transition temperature on the interlayer distance, and on the number of adjacent layers in multilayered homologous compounds. Moreover, the model has a potential to explain (i) a mismatch between the optimal doping levels for critical temperature and superconducting density and (ii) a universal scaling relation between the dc-conductivity, the superfluid density, and the superconducting transition temperature.