Modified method for determining nonlinear refractive index of 2,5-Dimethyl Aniline(DMA) in chloroform solution by Z-scan

Abstract A modification to the well-known Z-scan technique for measuring optical non-linearities is introduced in which one has to take in account only the small portion of the obtained Z-scan transmittance curve where the approximation z ≪ z0 is applicable. The experiment is performed by measuring nonlinear refractive index, n2, of three different concentrations of 2,5-Dimethyl Aniline (DMA) dissolved in chloroform for three different wavelengths with a set of varying incident powers. The Z-scan results give a negative n2 with a magnitude of the order of 10−14 esu. The comparison of the applied method with the usual Z-scan curve fitting theory reveals the effectiveness and the simplicity of this method.