Title :
Threshold lowering in GaN micropillar lasers by means of spatially selective optical pumping
Author :
Rex, Nathan B. ; Chang, Richard K. ; Guido, Louis J.
Author_Institution :
Dept. of Appl. Phys., Yale Univ., New Haven, CT, USA
Abstract :
A new optical pumping method is demonstrated for creating a population inversion in GaN micropillar cavities with circular symmetry. This approach employs an axicon lens to produce a ring-shaped optical beam and provides for independent control of ring thickness and diameter. By bringing the pump beam into coincidence with whispering gallery modes confined near the outer rim of the cavity, we achieve a significant reduction in the threshold pump intensity for room-temperature operation of GaN micropillar lasers.
Keywords :
III-V semiconductors; MOCVD; gallium compounds; laser accessories; laser beams; laser cavity resonators; laser modes; lenses; microcavity lasers; optical pumping; population inversion; semiconductor lasers; 298 K; GaN; GaN micropillar cavities; GaN micropillar lasers; axicon lens; cavity; circular symmetry; independent control; optical pumping method; population inversion; pump beam; ring diameter; ring thickness; ring-shaped optical beam; room-temperature operation; spatially selective optical pumping; threshold lowering; threshold pump intensity; whispering gallery modes; Gallium nitride; Laser beams; Laser excitation; Lenses; Optical beams; Optical control; Optical pumping; Pump lasers; Ring lasers; Thickness control;
Journal_Title :
Photonics Technology Letters, IEEE
