Second harmonic generation of metal nanoparticles under tightly focused illumination

作者:Sun, Jing-Wei; Wang, Xiang-Hui*; Chang, Sheng-Jiang; Zeng, Ming; Zhang, Na
来源:Chinese Physics B, 2016, 25(3): 037803.
DOI:10.1088/1674-1056/25/3/037803

摘要

The near-field and far-field second harmonic (SH) responses of a metal spherical nanoparticle placed in the focal region of a highly focused beam are investigated by using the calculation model based on three-dimensional finite-difference time-domain (FDTD) method. The results show that off-axis backward-propagating SH response can be reinforced by tightly focusing, due to the increase of the relative magnitude of the longitudinal field component and the phase shift along the propagation direction.