Very-low-threshold index-confined planar microcavity lasers

A fabrication process for laterally index-confined planar microcavity lasers is given that results in continuous-wave thresholds as low as 59 μA for a properly tuned cavity (T=250 K). Characterization of the spontaneous emission mode shows that the lateral confinement, when reduced to the mode size expected for the planar cavity, appears to increase the spontaneous emission coupling to the lasing mode.