Extraordinary characteristics of one-dimensional 𝒫𝒯-symmetric ring optical waveguide networks with near-isometric and isometric arms

¹ Provincial Key Laboratory of Nanophotonic Functional Materials and Devices, School of Information and Optoelectronic Science and Engineering, South China Normal University - Guangzhou 510006, China
² Laboratory of Ultrafast Optics, School of Electronic and Computer Engineering, Peking University Shenzhen 518055, China

^(a) xbyang@scnu.edu.cn (corresponding author)

Received: 29 June 2020
Accepted: 28 July 2020

Abstract

We construct one-dimensional -symmetric ring optical waveguide networks with near-isometric and isometric arms and investigate their extraordinary optical properties. It is found that the features for the former and the latter are quite different, although extraordinary ultrastrong transmission and reflection exist in both of them. When the former changes to be the latter, the extraordinary optical properties will all change remarkably, and the fitting formulae are obtained. The bidirectional invisibility only exists in the former and the principle is analyzed. This work may be helpful for designing ultra-narrow optical filters, ultra-sensitive optical switches, and resonant component for high-monochromatic lasing.