Broadband terahertz wavefront modulation based on flexible metasurface

• Published in: Optics communications Vol. 508; p. 127840
• Main Authors: Ren, Haiyang, Yue, Weiwei, Liu, Jian, Liu, Liyuan, Geng, Zhaoxin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.04.2022
• Subjects: Anomalous refraction; Broadband effect; Flexible metasurface; Phase gradient; THz wave; Vortex beam; Phase gradient; Vortex beam; Flexible metasurface; Broadband effect; THz wave; Anomalous refraction
• ISSN: 0030-4018
• DOI: 10.1016/j.optcom.2021.127840

To broaden the range of working frequency of the metasurface in the THz band, a flexible metasurface based on the parylene-C film was proposed. The metasurface is composed of elliptical split-ring units with different opening gaps. Elliptical split-ring units with different arrangement can work as 2D beam deflector, 3D beam deflector or vortex generator. The 2D beam deflector modulate THz waves with deflection angles (38°–13.5°) in the broad frequencies (0.6–1.6 THz), whereas the 3D beam deflector can realize beam deflection in 3D space, and the vortex beam generator can modulate THz wave as stable vortex beams carrying orbital angular momentum (OAM) in the broad frequencies (0.8–1.4 THz). The simulation results illustrate that the proposed flexible metasurface exhibits broadband effect in THz range, which promotes the application of flexible metasurfaces in the fields of THz optical field modulation and THz communication. •Flexible metasurface devices with broadband effect are created to modulate terahertz wavefront.•The 2D beam deflector achieves a wide range of angular deflection of the beam in the range of 0.6–1.6 THz.•The 3D beam deflector achieves the deflection of the beam in three-dimensional space.•The vortex beam generator works stably in the range of 0.8–1.4 THz, and can be used for THz broadband communication.