We have devised and experimentally verified a method for observation of the optical Kerr effect in microcavities at room temperature. The technique discriminates against the much larger and typically dominant thermal component of nonlinearity by using its relatively slow frequency response. Measurement of the Kerr coefficient or equivalently of the third-order nonlinear susceptibility of the cavity material is demonstrated for a silica microcavity. With this approach, useful information about the characteristic thermal response time in microresonators can also be acquired.
© 2005 Optical Society of America
(190.1900) Nonlinear optics : Diagnostic applications of nonlinear optics
(190.3270) Nonlinear optics : Kerr effect
(190.4360) Nonlinear optics : Nonlinear optics, devices
(230.5750) Optical devices : Resonators
Hossein Rokhsari and Kerry J. Vahala, "Observation of Kerr nonlinearity in microcavities at room temperature," Opt. Lett. 30, 427-429 (2005)