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arXiv · 1612.05904

Sum-Frequency and Second-Harmonic Generation from Plasmonic Nonlinear Nanoantennas

Xiaoyan Y. Z. Xiong·Li Jun Jiang·Wei E. I. Sha·Yat Hei Lo·Weng Cho Chew
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Abstract

Plasmonic nanostructures that support surface plasmon (SP) resonance potentially provide a route for the development of nanoengineered nonlinear optical devices. In this work, second-order nonlinear light scattering, specifically sum-frequency generation (SFG) and second-harmonic generation (SHG), from plasmonic nanoantennas is modeled by the boundary element method (BEM). Far-field scattering patterns are compared with the results calculated by the Mie theory to validate the accuracy of the developed nonlinear solver. The SFG from a multi-resonant nanoantenna (MR-NA) and the SHG from a particle-in-cavity nanoantenna (PIC-NA) are analyzed by using the developed method. Enhancements of the scattering signals due to double-resonance of the MR-NA and gap plasmonic mode of the PIC-NA are observed. Unidirectional nonlinear radiation for the PIC-NA is realized. Moreover, its emission direction can be controlled by the location of the nanosphere. This work provides new theoretical tools and design guidelines for plasmonic nonlinear nanoantennas.

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Xiaoyan Y. Z. Xiong, Li Jun Jiang, Wei E. I. Sha, Yat Hei Lo, Weng Cho Chew. 2016-12-18. Sum-Frequency and Second-Harmonic Generation from Plasmonic Nonlinear Nanoantennas. https://arxiv.org/abs/1612.05904

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