Electrically injected VCSEL with a composite DBR and MHCG reflector.

Abstract

We achieve the continuous-wave (CW) lasing of electrically-injected, first-of-their-kind vertical-cavity surface-emitting lasers (VCSELs) that use a subwavelength monolithic high-refractive-index-contrast grating (MHCG) mirror. The MHCG, unlike the well-known high-refractive-index-contrast grating (HCG) is neither a membrane suspended in the air nor a structure that requires a cladding layer. The MHCG is patterned in a semiconductor material atop the VCSEL cavity creating an all-semiconductor laser. Static measurements show CW operation of the VCSELs from room temperature up to 75 °C. The VCSEL with a 13.5 μm current oxide aperture diameter operates with quasi-single mode emission from threshold to rollover. Our results open a way to produce all-semiconductor surface emitting lasers emitting at wavelengths from the ultraviolet and the visible (GaN-based) to the infrared (InP- and GaSb-based) with a reduced vertical thickness and thus we believe the manufacturing costs potentially will be reduced by approximately up to about 90% in comparison to the typical DBR VCSELs. Our VCSELs have immediate and emerging applications in optical communication, illumination, sensing, and as light sources in photonic integrated circuits.