Both long-lived coherences and coherent population oscillations result in dramatic enhancement of a Kerr nonlinearity in atomic media at very low intensity of resonant light. We demonstrate the possibility of separating the contributions from these effects under certain experimental conditions. We report a study of the nonlinear optical properties of atomic media under a variety of experimental conditions at low light intensity, paying particular attention to self-focussing, diffraction and quasi-degenerate wave mixing.
© 2007 Optical Society of America
(190.0190) Nonlinear optics : Nonlinear optics
(190.4380) Nonlinear optics : Nonlinear optics, four-wave mixing
(270.0270) Quantum optics : Quantum optics
(270.1670) Quantum optics : Coherent optical effects
A. Akulshin, A. Sidorov, R. McLean, and P. Hannaford, "Enhanced Kerr Nonlinearity at Low Light Intensity," in Quantum-Atom Optics Downunder, OSA Technical Digest (CD) (Optical Society of America, 2007), paper QWE2.