title: Patterns in a quasiconfocal optical parametric oscillator.
abstract: The formation of transverse patterns in a triply resonant optical parametric oscillator is studied both numerically and analytically for a spherical cavity close to confocality. While the pump profile is Gaussian, the signal and idler intensities may be made of many rings, either stationary or time dependent. The mode selection and the time dependence are understood with the help of the linear stability analysis. It might explain observations reported for a quasiconfocal cavity with a KTP crystal.
authors.affiliation: Laboratoire de Photophysique Moléculaire, Bâtiment 210, Université Paris-Sud, Orsay Cedex, France.
authors.forename: M
authors.initials: M
authors.lastname: Le Berre
authors.forename: E
authors.initials: E
authors.lastname: Ressayre
authors.forename: A
authors.initials: A
authors.lastname: Tallet