Coexistence of superconductivity and excitonic pairing in a doped-biased double-layer system

TL;DR

This paper explores how superconductivity and excitonic pairing can coexist in a doped, biased double-layer square-lattice system, analyzing their dependence on various physical parameters to shed light on high-temperature superconductor mechanisms.

Contribution

It introduces a detailed model of coexistence of superconductivity and excitonic pairing in a doped-biased double-layer system considering multiple interactions and external influences.

Findings

Superconductivity is influenced by intralayer phonons affecting charge density.

The coexistence of superconductivity and excitonic pairing is demonstrated under certain conditions.

Insights into high-$T_c$ cuprate superconductors are provided.

Abstract

The subject of the present study is the double-layer square-lattice system with the intralayer phonon modulations. We investigate the superconducting and excitonic pairings, as well as their coexistence, as functions of various physical parameters in the system. These parameters include temperature, intralayer and interlayer Coulomb interactions, the electron-phonon coupling parameter, doping and the applied electric field. The existence of superconductivity is demonstrated by considering the influence of intralayer phonons on the total charge density leading to the modification of the total energy of the electrons. Our results provides insights into the long-standing problem of the mechanism of superconductivity in high-$T_c$ cuprate superconductors.