Low-Threshold Continuous-Wave Lasing in Photopumped GaInAsP Microdisk Lasers

Abstract
We demonstrated continuous-wave lasing at room temperature in a photopumped GaInAsP microdisk laser fabricated by Cl2/Xe inductively coupled plasma etching. The minimum threshold pump power was as low as 30 µW. This value is 0.7 times the lowest threshold in the current injection device due to the uniform carrier distribution by photopumping. Higher thermal resistance and odd-order azimuthal mode lasing as a result of a narrower pedestal and no upper post structure were observed.