Intrinsic Carrier Losses in Tellurium Due to Radiative and Auger Recombinations

TL;DR

This study uses microscopic models to analyze carrier losses in bulk tellurium, revealing that Auger recombination dominates at high densities and is highly sensitive to band structure, with radiative losses being comparatively lower.

Contribution

First-principles models are applied to quantify radiative and Auger recombination losses in tellurium, highlighting the critical dependence of Auger processes on valence band positions.

Findings

Auger processes dominate carrier losses at typical laser densities.

Auger coefficient varies significantly with temperature and band position.

Radiative losses are lower than in bulk III-V materials at similar wavelengths.

Abstract

Fully microscopic many-body models based on inputs from first principle density functional theory are used to calculate the carrier losses due to radiative- and Auger-recombinations in bulk tellurium. It is shown that Auger processes dominate the losses for carrier densities in the range typical for applications as lasers. The Auger loss depends crucially on the energetic position of the $H_6$ valence bands. At cryogenic temperatures of 50$\,$K (100$\,$K) the Auger coefficient, $C$, varies by about six (three) orders of magnitude within the range of published distances between these bands and the valence bandedge. Values for $C$ at the high and low end of these ranges are found if the distance is smaller or larger than the bandgap, respectively. At room temperature the sensitivity is reduced to about a factor of four with $C$ values ranging between $0.4$ and $1.6\times 10^{-27}$cm$^6$s$^{-1}$. Here, radiative losses dominate for carrier densities up to about $10^{16}/$cm$^3$ with a loss coefficient $B\approx 10^{-11}$cm$^3$s$^{-1}$. The radiative losses are about two to three times lower than in typical bulk III-V materials for comparable wavelengths.