The nonlinear optical response for index-matched, non-absorbing immiscible phases (liquid-solid, liquid-liquid, solid-solid) has been determined by means of open aperture z-scan measurements. In mixtures where one constituent shows a relatively high optical nonlinearity, rapid and reversible transformation to a light-scattering state is observed under conditions where a critical incident light fluence is exceeded. This passive broadband response is induced by a transient change in the dispersive part of the refractive index, and is based upon the Christiansen-Shelyubskii filter that at one time was used as a means to monitor the temperature of glass melts. Modeling studies are used to simulate scattering intensities in such textured composits as a function of composition, microstructure, and constituent optical properties. Results provide a rational approach to the selection of materials for use in these limiters. Challenges to preparing dispersed phase mixtures and their response to 532 nm nanosecond pulsed laser irradiation are described.
Revised: December 2, 2004 |
Published: June 1, 2004
Citation
Exarhos G.J., and K.F. Ferris. 2004.Optical Limiting by Index-Matched Phase-Segregated Mixtures. In Quantum sensing and nanophotonic devices : Proceedings of SPIE--the International Society for Optical Engineering, 29-25 January, 2004, San Jose, California, USA /, edited by Manijeh Razeghi, Gail J. Brown, 5359, 309-323. Bellingham, Washington:SPIE.PNNL-SA-40502.