We have observed enhanced optical limiting behavior in solutions of a derivatized fullerene (phenyl-C61-butyric acid cholesteryl ester) from 532 to 700 nm. Transient absorption measurements determined the spectral and temporal regions of interest for optical limiting in C60 and in C60 derivatives that are due to a reverse saturable absorption mechanism and predicted enhanced limiting at longer wavelengths. Intensity-dependent transmission measurements made at several wavelengths confirmed these results. The increased solubility and the broadened ground-state absorption of the functionalized C60 make it suitable for use as an optical limiter in the red and the near infrared.
© 1996 Optical Society of America
Original Manuscript: December 19, 1995
Published: July 1, 1996
L. Smilowitz, H. Wang, F. Wudl, D. McBranch, V. Klimov, J. M. Robinson, A. Koskelo, M. Grigorova, and B. R. Mattes, "Enhanced optical limiting in derivatized fullerenes," Opt. Lett. 21, 922-924 (1996)