中国物理B ›› 2006, Vol. 15 ›› Issue (11): 2618-2622.doi: 10.1088/1009-1963/15/11/027
孙香冰1, 任诠1, 杨洪亮1, 冯林1, 刘智波2, 王新强3, 张光辉3, 许东3
Sun Xiang-Bing(孙香冰)a)†, Ren Quan(任诠)a)‡, Wang Xin-Qiang(王新强)b), Zhang Guang-Hui(张光辉)b), Yang Hong-Liang(杨洪亮)a), Feng Lin(冯林)a), Xu Dong(许东)b), and Liu Zhi-Bo(刘智波)c)
摘要: The third-order optical nonlinearities of [(CH$_3$)$_4$N]Au(dmit)$_2$ (dmit = 4,5-dithiolate-1,3-dithiole-2-thione) at 532\,nm and 1064\,nm are investigated using the $Z$-scan technique with pulses of picoseconds duration. The $Z$-scan spectra reveal a strong nonlinear absorption (reverse saturable absorption) and a negative nonlinear refraction at 532\,nm. No nonlinear absorption is observed at 1064\,nm. The molecular second-order hyperpolarizability $\ga$ for the [(CH$_3$)$_4$N]Au(dmit)$_2$ molecule at 532\,nm is estimated to be as high as (2.1 $\pm$ 0.1) $\ti$ 10$^{-31}$\,esu, which is nearly three times larger than that at 1064\,nm. The mechanism responsible for the difference between the results is analysed. Nonlinear transmission measurements suggest that this material has potential applications in optical limiting.
中图分类号: (Optical susceptibility, hyperpolarizability)