Temperature Dependence and Screening Models in Quantum Cascade Structure

TL;DR

This paper compares various screening models in quantum cascade lasers, highlighting the significant impact of impurity scattering on optical linewidth that increases with temperature, and identifies conditions where simple models are effective.

Contribution

It evaluates the effectiveness of different screening models in quantum cascade structures and clarifies when simple isotropic bulk screening models are appropriate.

Findings

Impurity scattering significantly affects optical linewidth.

The impact of impurity scattering increases with temperature.

Simple isotropic bulk screening models are effective under certain conditions.

Abstract

Different screening models in quantum cascade lasers are compared by calculating the contribution of intra-subband impurity scattering to the optical linewidth as a function of temperature. We find a strong impact of impurity scattering which is increasing substantially with temperature. A simple isotropic bulk screening model works well if the screening length is of the order or longer than the period length of the cascade structure.