Local polarization state observation and third-order nonlinear susceptibility measurements by self-induced polarization state changes method

We report on a new method appropriate to the study of the polarization stat es of the electromagnetic field at the output of nonlinear medium. The nove lty here is the measurement of the elliptical parameters of the polarizatio n state field function of the input laser intensity. New relations were fou nd to estimate the local ellipticity e(r) and the local polarization ellips e rotation theta(r) at the output of the medium. In order to check the reli ability of the proposed method, we have confronted this one to determine th e third-order nonlinear susceptibility tensor components chi(xyyx)([3]). Th e comparison between the values obtained by this approach and some previous values from the literature was entirely satisfying. For instance, we have obtained the chi(xyyx)([3]) (CS2) = 6.5 x 10(-20) m(2)V(-2) with a 10% rela tive error. (C) 2000 Published by Elsevier Science B.V.