Directional single-mode emission from InGaAs/GaAs quantum-dot half-disk microlasers
We report on the fabrication and studies of
Ø100 μm half-disk lasers with an active region based on
InGaAs/GaAs quantum dots providing very high modal gain.
Such resonators support whispering gallery modes propagating
at the cavity periphery. The microlasers show directional light
outcoupling: continuous-wave output power emitted from the
flat side reaches 17 mW, which is about 7 times greater than
the power emitted from the back semicircular side. Single-mode
lasing in a wide range of the injection currents is observed. P-side
down bonding of the devices onto Si-board allowed increasing the
maximum optical power to more than 30 mW and the lasing was
observed up to 93C. The 3 dB modulation bandwidth of 4.6 GHz
was measured likely being limited by RC-parasites.