On the temperature dependence of ballistic Coulomb drag in nanowires

TL;DR

This paper theoretically analyzes how Coulomb drag current in nanowires depends on temperature and voltage, revealing conditions for decreasing current with temperature, saturation at high voltages, and the impact of screening effects.

Contribution

It provides a Fermi liquid theory explanation for the temperature dependence of Coulomb drag in nanowires, including experimental observations and screening effects.

Findings

Drag current can decrease with temperature within certain ranges

The observed T^{-0.77} dependence aligns with Fermi liquid theory

At high voltages, drag current saturates

Abstract

We have investigated within the theory of Fermi liquid dependence of Coulomb drag current in a passive quantum wire on the applied voltage $V$ across an active wire and on the temperature $T$ for any values of $eV/k_BT$. We assume that the bottoms of the 1D minibands in both wires almost coincide with the Fermi level. We come to conclusions that 1) within a certain temperature interval the drag current can be a descending function of the temperature $T$; 2) the experimentally observed temperature dependence $T^{-0.77}$ of the drag current can be interpreted within the framework of Fermi liquid theory; 3) at relatively high applied voltages the drag current as a function of the applied voltage saturates; 4) the screening of the electron potential by metallic gate electrodes can be of importance.