Polarization Properties of InGaN Vertical-Cavity Surface-Emitting Laser With Pipe Distributed Bragg Reflector

Indium gallium nitride (InGaN) vertical-cavity surface-emitting lasers (VCSELs) with top dielectric and bottom pipe-gallium nitride (GaN) distributed Bragg reflectors (DBRs) were demonstrated. Pipe-GaN DBR structure consisted of a lateral wet-etched pipe-GaN layer and a GaN layer in the 20 pair stack structure as an embedded reflector. The optical birefringence behavior of the anisotropic pipe-GaN structure induced the polarization properties in the reflectance and electroluminescence (EL) spectra. Polarization EL emission peaks with narrow line-widths were measured at 430.8 nm (perpendicular to pipe-GaN) and 432.5 nm (along with pipe-GaN), respectively. The EL emission peaks with high polarization ratios were observed due to the short resonance cavity effect with the birefringence pipe-GaN DBR structure.