Improved optical efficiency of GaAs-based infrared vertical-cavity surface-emitting laser enabled by combining a metallic reflector and a Bragg reflector

The use of coupled reflectors was investigated to improve the device performance of GaAs-based 860 nm vertical-cavity surface-emitting lasers (VCSELs). Here, the combined reflector was fabricated by coupling a metallic reflector (Ag) and a distributed Bragg reflector of an epitaxial structure. The performance parameters of the VCSEL, such as light-emitting efficiency, operational voltage, and power consumption, were dramatically improved by using a combined reflector. As a result, infrared GaAs-based VCSELs with combined reflectors could show superior light-emitting performance and reduced operational threshold voltage characteristics compared to conventional VCSELs.