Intrinsic carrier losses in tellurium due to radiative and Auger recombinations

Abstract

Fully microscopic many-body models based on inputs from first principles 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 how far energetically lower hole bands are detuned from the valence band edge. Values for this detuning range throughout literature from being about equal to the bandgap to being on the order of 100 meV larger than the bandgap. We find that at cryogenic temperatures of 50 K (100 K), the Auger coefficient, C, is about six (three) orders of magnitude smaller if this detuning is as in our calculations at the low end of the published values rather than at the high end where it exceeds the bandgap. At room temperature, the sensitivity is reduced to about a factor of four with C values ranging between 0.4 and [Formula: see text] cm6 s−1. Here, radiative losses dominate for carrier densities up to about [Formula: see text] cm3 with a loss coefficient [Formula: see text] cm3 s−1. The radiative losses are about two to three times lower than in typical bulk III–V materials for comparable wavelengths.

Theory and optimisation of radiative recombination in broken-gap InAs/GaSb superlattices

“…including miniband dispersion and q-dependent optical matrix elements -yields B = 1.81 × 10 −11 cm 3 s −1 for an InAs/GaSb SL having t InAs = t GaSb = 2.14 nm. This value is close to B computed for bulk InAs from first principles [83] and compares favourably with that we have previously calculated for novel GaAs-based metamorphic InAs 1−x Sb x /Al y In 1−y As and InP-based pseudomorphic In y Ga 1−y As 1−x Bi x /In 0.53 Ga 0.47 As mid-infrared QWs having spatially direct (type-I) carrier confinement [64,84]. For example, this calculated value of B is ≈ 31% of the value B = 5.88 × 10 −11 cm 3 s −1 we previously computed for a type-I InAs/Al 0.125 In 0.875 As metamorphic QW at the same temperature and carrier density [64].…”

Microscopic analysis of linear and nonlinear electro-optical properties of tellurium

“…As shown in Ref. [10], the data for the radiative losses can be fitted assuming a T −7/4 -dependence. Assuming the valence band splitting is 333 meV the dependence of the Auger losses can be fitted by…”

“…The microscopic theory used here is outlined in Refs. [9,10] and Refs therein. Absorption and gain spectra are calculated with the semiconductor Bloch equations (SBE) and photoluminescence (PL) (spontaneous emission) as well as the related radiative carrier lifetime are calculated by solving the semiconductor luminescence equations (SLE).…”