LO-phonon overheating in quantum dots

TL;DR

This paper investigates the passive behavior of LO phonons in quantum dots, analyzing existing models and proposing an improved method using the Lang-Firsov transformation to enhance phonon bath passivity.

Contribution

It identifies limitations in current approximations of electronic transport in quantum dots and introduces a canonical transformation to improve LO phonon bath passivity.

Findings

Existing models show limited phonon bath passivity.

The Lang-Firsov transformation enhances phonon bath passivity.

Improved models better represent long-term energy relaxation.

Abstract

Longitudinal optical phonons have been used to interpret the electronic energy relaxation in quantum dots and at the same time they served as a reservoir, with which the electronic subsystem is in contact. Such a phonon subsystem is expected to be passive, namely, in a long-time limit the whole system should be able to achieve such a stationary state, in which statistical distributions of both subsystems do not change in time. We pay attention to this property of the LO phonon bath. We show the passivity property of the so far used approximations to electronic transport in quantum dots. Also we show a way how to improve the passivity of LO phonon bath using canonical Lang-Firsov transformation.