Tunable multifunctional polarization conversion in bilayer chiral metamaterials

A chiral metamaterial composed of bilayer twisted split-ring resonators is proposed and demonstrated to realize tunable, dual-directional, and multifunctional polarization conversion for terahertz waves. Simulations show that the converter can selectively achieve linear-to-linear, linear-to-right-handed circular, or linear-to-left-handed circular polarization conversion by tuning the polarization and propagating direction of the incident waves. Stokes parameters, ellipticity, and a polarization rotation angle are introduced to determine the output polarization. The circular polarization transmission coefficients and surface current distribution are employed to demonstrate the physical mechanisms of the phenomena above. The proposed converter can find potential applications in terahertz imaging and communications. (c) 2023 Optica Publishing Group

Automated summary

A chiral metamaterial made of bilayer twisted split-ring resonators is proposed to achieve tunable, dual-directional, and multifunctional polarization conversion for terahertz waves. Simulations show that different types of polarization conversion can be achieved by adjusting the polarization and propagating direction of the incident waves. The physical mechanisms of the converter are demonstrated by circular polarization transmission coefficients and surface current distribution.