NONLINEAR OPTICAL PROPERTIES OF FULLERENE (C70) THIN FILMS

Abstract

C70 fullerenes evaporated onto rubbed polyimide substrates at greater than 150°C were found to orient almost parallel to the rubbing direction, as confirmed by atomic force microscopy and polarized absorption analysis. The directions of maximum absorption, including both linear and nonlinear absorption components, also appeared to be aligned with the rubbing direction. The third-order electrical susceptibility of the evaporated C70 fullerenes thin films was measured using a z-scan method and found to be χ(3)=Im χ(3): 10−6∼10−8 esu at a wavelength of 500 nm.