Study of Third- and Fifth-Order Nonlinear Optical Processes in Thin C60 Films.

The nonlinear refraction in thin films of fullerene C60 (100 nm) is studied by the Z- and RZ-scan methods using the second harmonic of a picosecond Nd:YAG laser (λ = 532 nm, τ = 55 ps). The combined effect of n2 (self-focusing of laser radiation) and n4 (self-defocusing) is analyzed. Mechanisms responsible for the nonlinear refraction in films are discussed. © 2005 Pleiades Publishing, Inc. [ABSTRACT FROM AUTHOR]