Graphene Metasurfaces for Light Manipulation and Sensing

Graphene metasurfaces constitute an emergent class of two-dimensional photonic interfaces in which patterned graphene elements are arranged on the subwavelength scale to engineer light–matter interactions. By exploiting the gate-tunable optical conductivity of graphene and its ability to support tightly confined surface plasmons, such metasurfaces can dynamically modulate the phase, amplitude and polarisation of electromagnetic waves across terahertz to mid-infrared frequencies. This active control is achieved by adjusting the Fermi level through electrical biasing, enabling reconfigurable beam steering, lensing, spectral filtering and sensing functions without mechanically altering the device. Graphene metasurfaces are particularly attractive for on-chip photonic integration, lightweight flat optics, compact spectrometers and highly sensitive chemical or biochemical sensors. Their ultrathin form factor, broadband operation and potential for high-speed modulation open avenues for adaptive optical systems in communications, security screening and environmental monitoring.

Research from Nature Portfolio

A pioneering work demonstrated that ribbon-patterned graphene atop a subwavelength optical cavity can deliver full 2π phase control and high reflection efficiency in the infrared by varying the ribbon width. This platform produced anomalous reflection, focusing lenses and nondiffracting beams on demand. A separate study harnessed a graphene-embedded polymer substrate with metallic patches to achieve electrically tunable phase gradients at terahertz frequencies. By modulating the Fermi energy, researchers realised dynamic switching between single and dual beam reflection at normal and oblique angles, promising agile beam routing devices. More recently, a graphene-based metasurface modulator has been employed in mid- to long-wave infrared computational spectroscopy. Low-voltage biasing yields distinct reflection spectra that, when processed through reconstruction algorithms, accurately recover unknown incident spectra, indicating a route to compact, on-chip spectrometers.

Graphene Metasurfaces for Light Manipulation and Sensing publication trend

The graph below shows the total number of articles in graphene metasurfaces for light manipulation and sensing across all publications each year (not limited to Nature Index journals).

Technical terms

Metasurface: An engineered, planar array of subwavelength scatterers that tailor the wavefront of light by imparting spatially varying phase, amplitude or polarisation changes.

Surface plasmon: A collective oscillation of free carriers at the interface between a conductor (such as graphene) and a dielectric, enabling strong confinement of electromagnetic fields.

Fermi level: The chemical potential of electrons in graphene, which determines its optical conductivity and can be adjusted by electrical gating.

Phase modulation: Controlled variation of the phase of reflected or transmitted light, used for beam shaping and focusing.

Spatial light modulator: A device that imposes programmable spatial patterns onto an optical wavefront, used in imaging and display technologies.

Terahertz (THz) regime: The region of the electromagnetic spectrum between microwave and infrared frequencies (approx. 0.1–10 THz), of interest for sensing and communications.

References

1. Graphene Plasmonic Metasurfaces to Steer Infrared Light. Scientific Reports (2015).
2. Terahertz beam switching by electrical control of graphene-enabled tunable metasurface. Scientific Reports (2017).
3. Mid- to long-wave infrared computational spectroscopy with a graphene metasurface modulator. Scientific Reports (2020).
4. Wavefront reconfigurable metasurface through graphene micro-ribbons with resonant strategy. Results in Physics (2023).
5. Graphene aperture-based metalens for dynamic focusing of terahertz waves.. Optics Express (2018).
6. Hybrid graphene metasurfaces for high-speed mid-infrared light modulation and single-pixel imaging. Light: Science & Applications (2018).