We reporr the first observation of the simultaneous creation and competition between a free-carrier light-induced diffraction grating and an accompanying thermal grating in gallium phosphide. The lifetimes of the two gratings are widely different and the nonlinear index n, = I x lo-" cm'lW for the free-carrier grating is almost an order of magnitude larger rhan the thermal effect of a 100-psec mode-locked pulse. 0 1992 John Wilqv & Sons, Inc. ABSTRACT I n this article the norion of transition function is reviewed under a mathemarical form: Two methods are explored which respectively lead to two different transition functions. Thes are used to make usynprotic evaluations of an eruct integral representation. Original anulyric formulations are established. Their main properties are presented and compared with orher diffracrion coe,fjScients which alreadv exist. Several numerical cotnpu~ations allow us to give an idea of the accuracy of' each formulation. 0 1992 Johrt W i l q & Sorts. ltic.

No abstract

No abstract

No abstract

No abstract