GaAs MICRODISK CAVITIES FOR SECOND-HARMONIC GENERATION

Paulina S. Kuo, John Lawall, and Glenn S. Solomon

Nonlinear optical frequency conversion can be highly efficient in whispering-gallery-mode microcavities due to the possibility for strong light confinement and good modal overlap. However, efficient conversion also requires phasematching between the interacting waves. GaAs and other materials possessing 4-bar symmetry offer quasi-phasematching (QPM) in curved propagation geometries without external domain inversions, which can enable efficient frequency conversion in microdisks. I will describe 4-bar quasi-phasematching in GaAs microdisks and describe experiments to observe 4-bar QPM in second-harmonic generation. Devices based on wavelength conversion in GaAs microdisks are of interest for spectroscopy, sensing, and quantum information.