Polariton-induced superconductivity in two-dimensional metals

TL;DR

This paper proposes a novel method to induce high-temperature superconductivity in 2D metals, specifically twisted bilayer graphene, via resonant coupling with nearby polar dielectric phonons, supported by Eliashberg equation analysis.

Contribution

It introduces a new approach to achieve superconductivity in 2D metals through dielectric environment engineering, combining plasmon-phonon coupling with numerical Eliashberg solutions.

Findings

Superconductivity can be induced in 2D metals by dielectric environment modification.

Resonant coupling between plasmons and phonons enhances pairing.

Predicted high-temperature superconductivity in twisted bilayer graphene near specific angles.

Abstract

The electronic properties of two-dimensional (2D) metals are altered by changes in their three-dimensional dielectric environment. In this Letter we propose that superconductivity can be induced in a 2D metal by resonant coupling between its plasmonic collective modes and optical phonons in a nearby polar dielectric. Specifically, we predict that relatively high-temperature superconductivity can be induced in bilayer graphene twisted to an angle somewhat larger than the magic value by surrounding it with a THz polar dielectric. Our conclusions are based on numerical solutions of Eliashberg equations for massless Dirac fermions with tunable Fermi velocities and Fermi energies, and can be understood qualitatively in terms of a generalized McMillan formula.