Full-range Gate-controlled Terahertz Phase Modulations with Graphene Metasurfaces

TL;DR

This paper presents a method for full-range, active phase modulation of terahertz waves using gate-tuned graphene metasurfaces, enabling dynamic control of electromagnetic wavefronts for advanced photonic applications.

Contribution

It introduces a novel graphene-based metasurface design that achieves full-range active phase modulation in the terahertz regime, supported by a resonator model and simulations.

Findings

Achieved full-range phase modulation in THz using graphene metasurfaces

Demonstrated a gate-tunable THz polarization modulator

Provided a resonator model explaining the phase control mechanism

Abstract

Local phase control of electromagnetic wave, the basis of a diverse set of applications such as hologram imaging, polarization and wave-front manipulation, is of fundamental importance in photonic research. However, the bulky, passive phase modulators currently available remain a hurdle for photonic integration. Here we demonstrate full-range active phase modulations in the Tera-Hertz (THz) regime, realized by gate-tuned ultra-thin reflective metasurfaces based on graphene. A one-port resonator model, backed by our full-wave simulations, reveals the underlying mechanism of our extreme phase modulations, and points to general strategies for the design of tunable photonic devices. As a particular example, we demonstrate a gate-tunable THz polarization modulator based on our graphene metasurface. Our findings pave the road towards exciting photonic applications based on active phase manipulations.