Sign-reversal of drag in bilayer systems with in-plane periodic potential modulation

TL;DR

This paper presents a theoretical study of frictional drag in bilayer systems with in-plane periodic potential modulation, revealing that the transresistivity can change sign with carrier density variations at low temperatures.

Contribution

It introduces a new theory for drag in bilayer systems with in-plane modulations and explains the sign reversal of transresistivity.

Findings

Transresistivity can change sign with carrier density.

Sign reversal occurs at low temperatures.

Physical explanation for sign change provided.

Abstract

We develop a theory for describing frictional drag in bilayer systems with in-plane periodic potential modulations, and use it to investigate the drag between bilayer systems in which one of the layers is modulated in one direction. At low temperatures, as the density of carriers in the modulated layer is changed, we show that the transresistivity component in the direction of modulation can change its sign. We also give a physical explanation for this behavior.