Quantum friction between graphene sheets

TL;DR

This paper investigates quantum friction between two parallel graphene sheets, analyzing vacuum decay and frictional forces, revealing a threshold velocity related to graphene's Fermi velocity for friction to occur.

Contribution

It introduces a model for Casimir friction in graphene sheets, incorporating their unique properties and relative motion, and evaluates key observables like vacuum decay probability and frictional force.

Findings

Frictional effects only occur above a threshold sliding velocity.

The system's behavior depends on the Fermi velocity of graphene.

Vacuum decay probability is quantitatively evaluated.

Abstract

We study the Casimir friction phenomenon in a system consisting of two flat, infinite, and parallel graphene sheets, which are coupled to the vacuum electromagnetic (EM) field. Those couplings are implemented, in the description we use, by means of specific terms in the effective action for the EM field. They incorporate the distinctive properties of graphene, as well as the relative sliding motion of the sheets. Based on this description, we evaluate two observables due to the same physical effect: the probability of vacuum decay and the frictional force. The system exhibits a threshold for frictional effects, namely, they only exist if the speed of the sliding motion is larger than the Fermi velocity of the charge carriers in graphene.