Bifunctional dual-channel polarization converter based on Weyl semimetal multilayer structure

Abstract

In this paper, a multilayer structure (MS) of Weyl semimetals (WSMs) is utilized as the foundation for a polarization converter (PCT) having two different functions in two frequency channels. An analysis of the transmission spectrum of this layer structure at varying incident angles and polarization directions is also included. We define the polarization deflection angle ϕ and discuss the structure’s potential as a PCT with respect to the ϕ = 45° scenario. The incident angles were chosen as 0°, 5°, 10°, 15° and 20° for the analysis, and the results reveal that the incident linear polarization waves in the interval of 78.87 ∼ 81.90 THz can be effectively transformed into circular polarization ones for transmission case. While, for electromagnetic waves with frequencies ranging from 67.44 ∼ 72.11 THz, the direction of vibration for the electric field deflects by 45°. This work also provides positive insights into the design of polarization-related isolators, angle selectors, and other optical devices.