Nonlinear optical measurements play an important role in characterization of colloidal solution. The information obtained by nonlinear optics on the polarizability of molecules and nanocrystals in solution is important to understand the molecular dynamics , aggregation , and phase transformations and confirmation changes [3, 4] in solution. However, a z-scan technique  widely used for the third-order nonlinear optical susceptibility measurements can be hardly applicable to a highly scattered medium, such as colloidal solution, since this technique relies on the properties measurements for the transmitted beam. Hyper-Rayleigh scattering, on the other hand, is an incoherent technique and the signal is typically limited to single photons per incoming laser pulse . That is why it is necessary to design a method for fast, simple and in the same time accurate nonlinear optical characterization of solutions.
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