Picosecond angularly-resolved excite-probe measurements have been used to make the first identification of a negative refractive optoelectronic nonlinearity in the ZnSe material deposited in thin-film nonlinear interference filters. A positive thermal refractive nonlinearity becomes dominant within 6 ps. We attribute the ultrafast relaxation of the photoexcited carriers to surface recombination at grain boundaries within the material. © 1992.
|Number of pages||4|
|Publication status||Published - Apr 1992|