Multi-optical effects in two-dimensional photonic crystals of metallic pairs

¹ Institute of Electromagnetics and Acoustics and Department of Physics, Xiamen University Xiamen, Fujian 361005, China
² College of Information Science and Engineering, Fujian Provincial Key Laboratory of Light Propagation and Transformation, Huaqiao University - Xiamen 361021, China

^(a) duanqilin@stu.xmu.edu.cn
^(b) yingchen@hqu.edu.cn (corresponding author)
^(c) kcnyon@xmu.edu.cn (corresponding author)

Received: 22 May 2021
Accepted: 8 October 2021

Abstract

Beam steering in photonic crystals is significant in manipulating light beams. In this paper, we design self-collimation, beam splitting, and negative refraction effects in photonic crystals based on metallic pairs immersed in dielectric background. By using a single array of metallic pairs, a broadband and wide-angle self-collimation effect is achieved. Meanwhile, due to the extreme anisotropy, a beam splitting effect is achieved by utilizing the kissing of equi-frequency contours. We then restructure the unit cell with glide symmetry to achieve negative refraction effect in a wide frequency range and realize the effect of flat lens. To illustrate this phenomenon, a flat lens based on the restructured unit cell is designed and numerically demonstrated.