Large optical nonlinearities of new organophosphorus fullerene derivatives.
Optical nonlinearities of five new organophosphorus fullerene derivatives with similar structures were determined by the Z-scan method by use of a nanosecond-pulse laser at 532 nm. The experimental results demonstrate that the five derivatives have much larger excited-state absorption and nonlinear refraction than C60. The excited-state absorption cross sections are nearly two to three times that of C60. Using a five-level model to fit the experimental data, we obtained some parameters such as excited-state absorption and refraction cross sections. A simple analysis of correlations between molecular structure and nonlinear properties is given. Optical nonlinearities of the five new organophosphorus fullerene derivatives were compared with those of some other kinds of fullerene derivatives, and the results show that the nonlinearities of the new derivatives are the larger.
Liu
Zhi-Bo
ZB
Photonics Center, College of Physics, Nankai University, Tianjin 300071, China.
Tian
Jian-Guo
JG
Zang
Wei-Ping
WP
Zhou
Wen-Yuan
WY
Zhang
Chun-Ping
CP
Zheng
Jian-Yu
JY
Zhou
Ying-Chun
YC
Xu
Hua
H