Electron-phonon scattering in quantum point contacts

TL;DR

This paper investigates how acoustic phonons cause backscattering in quantum point contacts, leading to conductance corrections and anomalies, aligning with experimental observations of the 0.7 feature.

Contribution

It provides a theoretical analysis of phonon-induced conductance corrections and zero-bias anomalies in quantum point contacts, explaining experimental features.

Findings

Negative conductance correction due to phonons

Activated temperature dependence observed

Zero-bias conductance anomaly explained

Abstract

We study the negative correction to the quantized value $2e^2/h$ of the conductance of a quantum point contact due to the backscattering of electrons by acoustic phonons. The correction shows activated temperature dependence and also gives rise to a zero-bias anomaly in conductance. Our results are in qualitative agreement with recent experiments studying the 0.7 feature in the conductance of quantum point contacts.