Resonant optical nonlinearity of fullerenes in free-standing polymethyl methacrylate films
نویسندگان
چکیده
We have prepared films of polymethyl .methacrylate in which fullerenes (a mixture of C,, and C,,) are uniformly embedded. By performing both degenerate four-wave mixing experiments and h-radiance-dependent transmission measurements with nanosecond laser pulses of 608nm wavelength, the third-order nonlinear optical susceptibility of these films is determined to be of the order of 10-l’ esu. This susceptibility is dominated by its imaginary part. Excited-state absorption is the main mechanism responsible for the observed nonlinear susceptibility.
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