High-power, single-mode, Al-free InGaAs(P)/InGaP/GaAs distributed feedback diode lasers

Abstract The selective etching and oxide-free regrowth properties of the Al-free InGaAs(P)/InGaP/GaAs material system have been exploited at λ =968 nm to demonstrate a novel single-spatial-mode diode laser: the simplified antiresonant reflecting optical waveguide (S-ARROW) laser structure, and also to achieve single-mode DFB operation to record-high power levels. The device is fabricated using a three-step MOCVD growth process, incorporating a lower (i.e. below the active layer) grating for single-frequency operation, and an S-ARROW structure (above the active region) for spatial mode selectivity and stability. Devices with 6.5 μm wide emitting apertures operate single-frequency and single-spatial mode to 157 mW under CW operation.