Chinese Optics Letters, 2020, 18 (1): 011901, Published Online: Dec. 12, 2019
Wavelength-dependent nonlinear absorption of gold nanocages Download: 756次
Abstract
The dipole resonances of gold nanocages were investigated theoretically using finite difference time domain method. The results show that field enhancement is obtained at the walls of the gold nanocages. It is believed that the effect can cause a strong optical nonlinear property. To test the hypothesis, nonlinear absorption was investigated using a broadband 5 ns Z scan. It was found that at low intensities the sample shows saturable absorption (SA), while at higher intensities a switch from SA to reverse SA occurs. Moreover, the nonlinear absorption of the sample is sensitively wavelength-dependent, and, in the resonant region, saturation intensity is the largest.
Shuang Chen, Suying Yang, Yan Huang, Weiyan Jiao, Guanghua Fan, Yachen Gao. Wavelength-dependent nonlinear absorption of gold nanocages[J]. Chinese Optics Letters, 2020, 18(1): 011901.