Relevance of intra- and inter-subband scattering on the absorption in heterostructures

TL;DR

This paper provides an exact analysis of how intra- and inter-subband scattering influence the absorption lineshape in disordered quasi-2D heterostructures, highlighting the dominant scattering mechanisms for different spectral features.

Contribution

It offers a precise calculation of absorption lineshape considering both intra- and inter-subband scatterings, improving understanding of free carrier absorption in heterostructures.

Findings

Intra-subband scattering controls the central absorption peak.

Inter-subband scattering dominates the absorption tails.

Quantitative assessment of free carrier absorption magnitude.

Abstract

We analyze the absorption lineshape for inter-subband transitions in disordered quasi 2D heterostructures by an exact calculation. The intra-subband scatterings control the central peak while the tails of the absorption line are dominated by the inter-subband scattering terms. Our numerical study quantitatively assesses the magnitude of the free carrier absorption. The accuracy of different models currently used for gain/absorption is discussed.