Oxidised GaAs QW vertical-cavity lasers with 40%power conversion efficiency

Abstract
Using a solid source MBE and Be for p-type doping, the authors have fabricated 6 µm diameter multimode vertical-cavity lasers with GaAs quantum wells showing a 730 µA threshold current and a 8.5 mW output power. For the first time a maximum conversion efficiency > 40% is reported for GaAs based VCSELs. Singlemode devices exhibit a maximum output power of 1.2 mW and a sidemode suppression > 30 dB.