Nonresonant Saturation Absorption in Electrostatic Self-Assembly Films Containing Methanofullerene
ZHANG Xue-Ru1, OUYANG Qiu-Yun1, WANG Yu-Xiao1, JIANG Li1, SONG Ying-Lin1, LI Yu-Liang2, WEI Tai-Huei3
1Department of Physics, Harbin Institute of Technology, Harbin 150001
2Laboratory of Organic Solids, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080
3Department of Physics, National Chung-Cheng University, Ming-Hsiung, Chia-Yi, Taiwai, China
Nonresonant Saturation Absorption in Electrostatic Self-Assembly Films Containing Methanofullerene
1Department of Physics, Harbin Institute of Technology, Harbin 150001
2Laboratory of Organic Solids, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080
3Department of Physics, National Chung-Cheng University, Ming-Hsiung, Chia-Yi, Taiwai, China
Abstract： Ultrathin films containing methaofullerene are prepared by electrostatic layer-by-layer self-assembly of a positively charged trifluoroacetic acid salt of monoamino-substituted methanofullerene (TMAF) derivative and a negatively charged poly (sodium 4-styrenesulfonate) (PSS). Absorptive optical nonlinearities of 30 bilayer TMAF/PSS films and TMAF in water solution are measured using the Z-scan technique at 532nm. Nonresonant saturation absorption is observed in the film sample, whereas reverse saturation absorption was for TMAF in water. The saturation-absorption behaviour is interpreted by a special formula. The saturation intensity is extracted to be 15.2±0.8MW/cm2. The mechanism of saturation absorption in the TMAF/PSS film is discussed.
2005, Vol. 22 
