FABRICATION OF INGAAS VERTICAL-CAVITY SURFACE-EMITTING LASERS BY MOLECULAR-BEAM EPITAXY ON (411)A GAAS SUBSTRATES AND ITS ROOM-TEMPERATURE OPERATION

We investigated the optimum growth conditions for fabrication of a hig h-reflective distributed Bragg reflector (DBR) with extremely flat het erointerfaces on (4 1 1)A GaAs substrates by molecular beam epitaxy (M BE). A high-reflective DBR consisting of AlAs/GaAs was successfully fa bricated under the investigated optimum conditions of 580 degrees C wi th V/III (As-4/Ga) ratio of similar to 8. Using this high-reflective D BR, we succeeded for the first time in the optically pumped pulse oper ation of InGaAs vertical-cavity surface-emitting lasers (VCSELs) at ro om temperature on (4 1 1)A GaAs substrates with improved threshold cha racteristics compared to conventional (1 0 0) GaAs substrates.