Auger recombination in InGaAs/AlGaAs-based MQW semiconductor lasers emitting at 980 nm

We have analysed experimentally the temperature and pressure dependence of 980 nm high-power GaAs/AlGaAs/lnGaAs semiconductor lasers in the temperature (7) range 80-350 K. Measurements of the threshold current and spontaneous emission allow us to study the underlying recombination occurring in the devices. We observe that up to approximate to250 K the dominant recombination mechanism is radiative (J(th) proportional to T). Above this temperature there is a super-linear increase in threshold current and a resulting decrease in the characteristic temperature, T-0 (approximate to 130 K at room temperature). Pressure measurements at room temperature allow us to differentiate between possible recombination processes. They show that leakage into the X minima accounts for only 0.1% of the total threshold current at atmospheric pressure and room temperature. We therefore conclude that Auger recombination is the cause of the super-linear increase in threshold current over the normal temperature range of operation.