Second harmonic generation of centrosymmetric nanospheres excited by tightly-focused doughnut beams  

作　　者：霍丙忠 王湘晖 常胜江 

机构地区：[1]Key Laboratory of Optical Information Science and Technology,Ministry of Education,Institute of Modern Optics,Nankai University

出　　处：《Optoelectronics Letters》2012年第3期161-164,共4页光电子快报（英文版）

基　　金：supported by the National High Technology Research and Development Program of China (No.2011AA010205);the National Natural Science Foundation of China (Nos.10704043 and 61171027);the Key Program of the Applied Basic Research of Tianjin (No.10JCZDJC15200);the Specialized Research Fund for the Doctoral Program of Higher Education of China (No.20090031110033)

摘　　要：Using the vector diffraction theory and the phenomenological model, this paper investigates the second harmonic tion （SHG） of a single centrosymmetric nanosphere excited by focused doughnut beams （DBs） with different topological charges. The results show that strong backward SHG （BSHG） appears when the particle is excited by focused DBs with topological charges of ±1. The backward second harmonic radiation can be caused by the depolarized effect of high numerical aperture （NA） objectives due to the strong longitudinal components.

关 键 词：Harmonic generation NANOSPHERES Nonlinear optics 

分 类 号：TB301[一般工业技术—材料科学与工程]