Off-Resonant Third-Order Optical Nonlinearity of Au Nanoparticle Array by Femtosecond Z-scan Measurement  

作　　者：王凯 龙华 付明 杨光 陆培祥 

机构地区：[1]Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and TechnoIogy, Wuhan 430074 [2]School of Science, Wuhan Institute of Technology, Wuhan 430073

出　　处：《Chinese Physics Letters》2010年第12期79-82,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China under Grant No 10974062, the National Science Fund for Distinguished Young Scholars under Grant No 60925021, and the National Basic Research Program of China under Grant No 2010CB923203.

摘　　要：A periodic triangular-shaped Au nanoparticle array is fabricated on a quartz substrate using nanosphere lithography and pulsed laser deposition, and the linear and nonlinear optical properties of metal particles are studied. The morphology of the polystyrene nanosphere mask （D = 820 nm） and the Au nanoparticle array are investigated by scanning electron microscopy. The surface plasmon resonance absorption peak is observed at 606 nm, which is in good agreement with the calculated result using the discrete dipole approximation method. By performing the Z-scan method with femtosecond laser （800 nm, 50 fs）, the optical nonlinearities of A u nanoparticle array are determined. The results show that the Au particles exhibit negative nonlinear absorption and positive nonlinear refractive index with the effective third-order optical nonlinear susceptibility Xeff^（3） can be up to （8.8 ± 1.0）× 10^-10 esu under non-resonant femtosecond laser excitation.A periodic triangular-shaped Au nanoparticle array is fabricated on a quartz substrate using nanosphere lithography and pulsed laser deposition, and the linear and nonlinear optical properties of metal particles are studied. The morphology of the polystyrene nanosphere mask （D = 820 nm） and the Au nanoparticle array are investigated by scanning electron microscopy. The surface plasmon resonance absorption peak is observed at 606 nm, which is in good agreement with the calculated result using the discrete dipole approximation method. By performing the Z-scan method with femtosecond laser （800 nm, 50 fs）, the optical nonlinearities of A u nanoparticle array are determined. The results show that the Au particles exhibit negative nonlinear absorption and positive nonlinear refractive index with the effective third-order optical nonlinear susceptibility Xeff^（3） can be up to （8.8 ± 1.0）× 10^-10 esu under non-resonant femtosecond laser excitation.

关 键 词：Condensed matter: electrical  magnetic and optical Surfaces  interfaces and thin films Nanoscale science and low-D systems 

分 类 号：O437[机械工程—光学工程] TQ426.64[理学—光学]