An empirical pseudopotential-based description of carrier scattering by LO phonons in semiconductor heterostructures

We have developed a model of LO phonon scattering in semiconductor heterostructures using the solutions of strained-layer empirical pseudopotential calculations with Fermi's Golden Rule. We have utilised this model to perform quantitative calculations of scattering lifetimes in GaSb/InAs photodetector superlattices over a temperature range of 50-400 K. The temperature dependencies of phonon absorption and emission by carriers are identified and the physical mechanisms behind these are traced. Comparisons with earlier calculations on elastic scattering due to isovalent defects are made. Phonon emission is found to be the dominant effect in most cases, exhibiting the shortest lifetimes and hence the largest scattering rates. These lifetimes are in the picosecond regime and are in good agreement with more widespread, envelope function-based calculations of phonon lifetimes in semiconductor heterostructures. © 2004 Elsevier Ltd. All rights reserved.