DEMONSTRATION OF INGAAS ALGAAS STRAINED-LAYER DISTRIBUTED-FEEDBACK GRATING-SURFACE-EMITTING LASERS WITH A BURIED 2ND-ORDER GRATING STRUCTURE

We have fabricated InGaAs/AlGaAs strained-layer distributed-feedback grating-surface-emitting lasers with a buried grating structure. The device consists of a pumped distributed-feedback section terminated on both sides by unpumped distributed Bragg reflector sections. cw operation in a stable single longitudinal mode is achieved up to six times threshold. The threshold current density is approximately 600 A/cm2. The far-field beam divergence is predominantly single lobed and diffraction limited. The spectral linewidth is 1.0 MHz at an output power of 8 mW.