Highly flexible broadband terahertz metamaterial quarter‐wave plate

TLDR

Metamaterials enable precise control of light propagation, intensity, and phase by designing artificial media, and engineered birefringence via metamolecules allows manipulation of electromagnetic wave phase for polarimetric devices. The paper presents a high‑efficiency, broadband, tunable, and flexible quarter‑wave plate based on a multilayer metamaterial. The device achieves broadband π/2 phase retardance with high transmission for terahertz waves, converting linearly polarized light into circular polarization across a wide frequency range. The quarter‑wave plate exhibits excellent achromatic π/2 phase retardance, high transmission, and numerically confirmed broadband conversion of linear to circular polarization, marking a significant advance for practical terahertz polarization devices.

Abstract

Abstract Metamaterials offer exciting opportunities that enable precise control of light propagation, its intensity and phase by designing an artificial medium of choice. Inducing birefringence via engineered metamolecules presents a fascinating mechanism to manipulate the phase of electromagnetic waves and facilitates the design of polarimetric devices. In this paper, a high‐efficiency, broadband, tunable and flexible quarter‐wave plate based on a multilayer metamaterial is presented. Excellent achromatic π/2 phase retardance with high transmission is observed upon terahertz propagation through the quarter‐wave plate. The calculated Stokes parameter represents the output polarization state numerically, indicating an excellent broadband conversion of linearly polarized light into circularly polarized light. The metamaterial‐based quarter‐wave plate demonstrated in this work could be an important step forward in the development of functional terahertz polarization conversion devices for practical applications.