Fabrication and characterization of a high Q microdisc laser using InAs quantum dot active regions

The microdisc device structure consists of GaAs substrate/Al0.5Ga0.5As sacrificing layer/GaAs cavity embedded with InAs quantum dot (QD) active regions. The entire device was grown using metal-organic molecular beam epitaxy (MOMBE). InAs QDs were grown by a self-assembling technique under S-K growth mode and capped by a GaNAs strain compensating layer (SCL). A free-standing microdisc was fabricated by employing e-beam lithography and wet-chemical etching. Emission characteristics were studied under photo-pumping mode. The highest quality factor (Q factor) of ∼7000 was achieved at 80 K excitation. The microdisc laser was characterized with room temperature operation (RT) at the wavelength of 1070.25 nm