来自纳米棱镜相位工程超表面的二次谐波产生

Second Harmonic Generation from Phase-Engineered Metasurfaces of Nanoprisms.

作者信息

Mochizuki Kanta, Sugiura Mako, Yogo Hirofumi, Lundgaard Stefan, Hu Jingwen, Ng Soon Hock, Nishijima Yoshiaki, Juodkazis Saulius, Sugita Atsushi

机构信息

Department of Applied Chemistry and Biochemical Engineering, Shizuoka University, 3-5-1 Johoku, Hamamatsu, Shizuoka 432-8561, Japan.

Optical Sciences Centre and ARC Training Centre in Surface Engineering for Advanced Materials (SEAM), School of Science, Swinburne University of Technology, Hawthorn, VIC 3122, Australia.

出版信息

Micromachines (Basel). 2020 Sep 12;11(9):848. doi: 10.3390/mi11090848.

DOI:10.3390/mi11090848

PMID:32932670

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7569796/

Abstract

Metasurfaces of gold (Au) nanoparticles on a SiO2-Si substrate were fabricated for the enhancement of second harmonic generation (SHG) using electron beam lithography and lift-off. Triangular Au nanoprisms which are non-centro-symmetric and support second-order nonlinearity were examined for SHG. The thickness of the SiO2 spacer is shown to be an effective parameter to tune for maximising SHG. Electrical field enhancement at the fundamental wavelength was shown to define the SHG intensity. Numerical modeling of light enhancement was verified by experimental measurements of SHG and reflectivity spectra at the normal incidence. At the plasmonic resonance, SHG is enhanced up to ∼3.5 × 103 times for the optimised conditions.

摘要

利用电子束光刻和剥离技术，在SiO₂-Si衬底上制备了金（Au）纳米颗粒超表面，以增强二次谐波产生（SHG）。研究了具有非中心对称且支持二阶非线性的三角形金纳米棱镜的SHG特性。结果表明，SiO₂间隔层的厚度是调节SHG最大化的有效参数。基波波长处的电场增强决定了SHG强度。通过垂直入射时SHG和反射光谱的实验测量，验证了光增强的数值模拟。在等离子体共振时，在优化条件下SHG增强高达约3.5×10³倍。