Coulomb drag by small momentum transfer between quantum wires

TL;DR

This paper shows that Coulomb drag in quantum wires is mainly caused by small momentum transfer processes, which are significant due to non-linear electron dispersion, leading to specific temperature-dependent behaviors.

Contribution

It reveals the importance of small momentum transfer processes in Coulomb drag, extending beyond conventional Luttinger liquid theory by considering non-linear dispersion effects.

Findings

Drag resistance scales as T^2 for identical wires

Drag resistance scales as T^5 for different wires

Small momentum transfer dominates Coulomb drag in a wide temperature range

Abstract

We demonstrate that in a wide range of temperatures Coulomb drag between two weakly coupled quantum wires is dominated by processes with a small interwire momentum transfer. Such processes, not accounted for in the conventional Luttinger liquid theory, cause drag only because the electron dispersion relation is not linear. The corresponding contribution to the drag resistance scales with temperature as T^2 if the wires are identical, and as T^5 if the wires are different.