基于方形腔耦合金属波导结构的全光等离子体开关

All-Optical Plasmonic Switches Based on Square Cavity Coupled Metal Waveguide Structure

摘要:

提出了一种新型的方形腔耦合金属波导结构,该结构由两个相互平行的矩形金属波导和一个内嵌可连通的方形谐振腔构成。利用方形谐振腔局域表面等离子体实现带阻滤波特性,并通过多路复用实现双端口全光等离子体开关。采用时域有限差分方法(FDTD)研究了方形腔的边长、折射率和谐振距离对强透射特性的影响。结果表明,基于方形腔耦合金属波导结构的光开关在工作中具有较好的阻带特性和透射特性,其最大透射率可达92%,最小阻带透射率达0.2%,工作波长范围为607~785nm。

Abstract:

A novel square cavity coupled metal waveguide structure is proposed, which is composed of two mutually perpendicular rectangular metal waveguides and a square resonant cavity connecting rectangular waveguides. The band-rejection filtering characteristics are realized by the plasma local characteristics of the square resonator, and the dual-port all-optical plasma switch is realized by multiplexing. The effects of the length, refractive index and resonance distance of the square cavity on the strong transmission characteristics were studied by the finite difference time domain method. The results show that the optical switch based on the square cavity coupled metal waveguide structure has better stop-band characteristics and transmission characteristics, and its maximum transmittance is 92%, the minimum stopband transmittance is 0.2%, and the working range is 607~785nm.