Abstract

Nonlinear optical effects are generally limited to the high-intensity regime due to the small value of typical nonlinear coefficients. We demonstrate novel effects where a strong spectator field mediates a large nonlinear interaction between two photons. Such effects open the door to a new field of {\it quantum} nonlinear optics, potentially useful for two-photon all-optical switches (e.g., optical quantum logic gates) as well as other nonlinear effects such as the formation of quantum solitons. I will talk about enhanced upconversion, quantum state preparation, two-photon cross-phase modulation, and potential quantum-information applications to tasks such as Bell state determination.

© 2002 Optical Society of America