title: 4-quasi-phase-matched interactions in GaAs microdisk cavities.
abstract: We describe quasi-phase-matched nonlinear interactions in materials that possess 4 symmetry, such as GaAs. 4 symmetry together with curved propagation geometries produce quasi phase matching (QPM) without need of external domain inversions. To improve efficiency of nonlinear optical mixing, 4 -QPM can be combined with resonant microcavities such as whispering-gallery-mode microdisks. All interacting waves must be resonant with the cavity, which leads to stringent tuning requirements. We show tuning behavior for second-harmonic generation in a GaAs microdisk cavity and estimate that, with milliwatt-level external pumping, approximately 0.1% power-conversion efficiency can be obtained with negligible higher-order nonlinear effects.
authors.affiliation: Physics Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA. pkuo@nist.gov
authors.forename: P S
authors.initials: PS
authors.lastname: Kuo
authors.forename: W
authors.initials: W
authors.lastname: Fang
authors.forename: G S
authors.initials: GS
authors.lastname: Solomon