Trap-Assisted Auger-Meitner Recombination from First Principles

TL;DR

This paper introduces a first-principles method to calculate trap-assisted Auger-Meitner recombination rates, revealing its dominance over traditional processes in wide-band-gap materials and impacting optoelectronic device efficiency.

Contribution

The authors develop a novel computational approach to quantify TAAM recombination, addressing limitations of previous models and applying it to a case study in InGaN.

Findings

TAAM rates are significantly higher than MPE rates in wide-band-gap materials.

TAAM can be the dominant nonradiative recombination process beyond 2.5 eV band gap.

The formalism is broadly applicable to various semiconductors and insulators.

Abstract

Trap-assisted nonradiative recombination is known to limit the efficiency of optoelectronic devices, but the conventional multi-phonon emission (MPE) process fails to explain the observed loss in wide-band-gap materials. Here we highlight the role of trap-assisted Auger-Meitner (TAAM) recombination, and present a first-principles methodology to determine TAAM rates due to defects or impurities in semiconductors or insulators. We assess the impact on efficiency of light emitters in a recombination cycle that may include both TAAM and carrier capture via MPE. We apply the formalism to the technologically relevant case study of a calcium impurity in InGaN, where a Shockley-Read-Hall recombination cycle involving MPE alone cannot explain the experimentally observed nonradiative loss. We find that, for band gaps larger than 2.5 eV, the inclusion of TAAM results in recombination rates that are orders of magnitude larger than recombination rates based on MPE alone, demonstrating that TAAM can be a dominant nonradiative process in wide-band-gap materials. Our computational formalism is general and can be applied to the calculation of TAAM rates in any semiconducting or insulating material.