Theory of BCS-like bogolon-mediated superconductivity in transition metal dichalcogenides

TL;DR

This paper introduces a new BCS-like superconductivity mechanism mediated by bogolon pairs in hybrid 2D systems involving transition metal dichalcogenides and exciton condensates, predicting higher critical temperatures.

Contribution

It develops a microscopic theory of bogolon-pair-mediated superconductivity and compares its strength to phonon and single bogolon mechanisms.

Findings

Bogolon-pair mechanism is stronger than phonon and single bogolon mechanisms.

Superconducting critical temperature depends on electron and condensate densities.

The theory predicts higher critical temperatures in certain parameter regimes.

Abstract

We report on a novel mechanism of BCS-like superconductivity, mediated by a pair of Bogoliubov quasiparticles (bogolons). It takes place in hybrid systems consisting of a two-dimensional electron gas in a transition metal dichalcogenide monolayer in the vicinity of a Bose-Einstein condensate. Taking a system of two-dimensional indirect excitons as a testing ground we show, that the bogolon-pair-mediated electron pairing mechanism is stronger than phonon-mediated and single bogolon-mediated ones. We develop a microscopic theory of bogolon-pair-mediated superconductivity, based on the Schrieffer-Wolff transformation and the Gor'kov's equations, study the temperature dependence of the superconducting gap and estimate the critical temperature of superconducting transition for various concentrations of the electron gas and the condensate densities.