Virtual Photon Contribution to Frictional Drag in double-layer Devices

TL;DR

This paper investigates how single photon exchange significantly contributes to frictional drag in double-layer fermion systems, challenging the usual second-order explanations and highlighting the importance of unscreened electromagnetic interactions.

Contribution

It introduces the first-order electromagnetic contribution to frictional drag, emphasizing the role of unscreened photon exchange in transresistance calculations.

Findings

Single photon exchange yields a finite, large contribution to transconductivity.

First-order effects are relevant in the d.c. limit, unlike traditional second-order explanations.

Unscreened electromagnetic interactions significantly impact frictional drag in bi-layer systems.

Abstract

The first order contribution to frictional drag in bi-layered fermion gas is examined. We discuss the relevance of single photon exchange in the evaluation of transresistance, which is usually explained by second order effects such as Coulomb and phonon drag. Since the effective e.m. interaction is unscreened, in the d.c. limit we obtain a finite (and large) contribution to transconductivity.