HIGH SINGLE-MODE OUTPUT POWER FROM COMPACT EXTERNAL MICROCAVITY SURFACE-EMITTING LASER-DIODE

Transverse mode control is demonstrated in an electrically pumped surf ace-emitting laser diode coupled to an external microcavity with room- temperature single-mode powers reaching 2.0 mW continuous wave and 36. 7 mW pulsed. The wavelength chirp is less than 0.044 nm for the pulsed results. The external microcavity is formed with a flat dielectric mi rror placed less than 700 mum from the wafer surface. Diffraction and spatial filtering in the external cavity provide high-order mode suppr ession and produce a large fundamental mode of width 36 mum. This exte rnal cavity geometry readily lends itself to integration.