Nonlinear complex susceptibility of cresyl violet solution measured with a dynamic grating method

The absolute square of the complex nonlinear third-order susceptibility chi /sub 3/ was investigated by measuring the self-diffraction efficiency eta of a transient laser-induced population grating. Cresyl violet in methanol was examined in the wavelength range of S/sub 0/ ground state absorption. For this dye, the real and imaginary parts of chi /sub 3/ were separated by additional determination of the nonlinear absorption. Both parts of chi /sub 3/ are plotted between 570 and 625 nm and their relation to each other was examined by using a Kramers-Kronig formula.<
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