title: Green bright squeezed light from a cw periodically poled KTP second harmonic generator.
abstract: We present the experimental observation of bright amplitude squeezed light from a singly resonant second harmonic generator (SHG) based on a periodically poled potassium titanyl phosphate (KTP) crystal. Contrary to conventional SHG, the interacting waves in this device couple efficiently using quasi phase matching (QPM) and more importantly QPM allows access to higher valued elements of the nonlinear tensor than is possible under the constraint of birefringence phase matching. We observe a noise reduction of 13% below the shot noise limit in the generated second harmonic field. This noise reduction is greater than what could be expected using normal birefringence phase matched KTP with the same experimental parameters. Excellent agreement between experiment and theory is found.
authors.forename: Ulrik
authors.initials: U
authors.lastname: Andersen
authors.forename: Preben
authors.initials: P
authors.lastname: Buchhave