Measurement of the third order nonlinear susceptibility of paratellurite single crystal using multiplex CARS

Abstract : We report the extraction of the real part of the third order nonlinear susceptibility for a c-cut paratellurite (TeO 2 − α) single crystal using the nonresonant contribution of the multiplex coherent anti-Stokes Raman scattering (M-CARS) signal. Using fused silica and SF57 as nonlinear reference materials, we derive the absolute value of the real part of the electronic third order susceptibility and we evidence the in-plane modulation of the nonlinear refractive index. These results are in total agreement with those recently obtained by the z-scan method.