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Updated: Aug 2, 2026
12:14
The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
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Gallium nitride-based geometric and propagation metasurfaces for vortex beam emissions.
Meng-Hsin Chen1, Yan-Liang Liu1, Vin-Cent Su1
1Department of Electrical Engineering, National United University, Miaoli 36003, Taiwan.
Heliyon
|February 9, 2024
Summary
This study showcases efficient gallium nitride (GaN) metasurfaces for generating vortex beams. One type achieves 99% efficiency, while the geometric version offers achromatic performance, overcoming dispersion limitations.
Area of Science:
- Optics and Photonics
- Materials Science
- Nanotechnology
Background:
- Metasurfaces offer advanced control over light properties.
- Vortex beams have applications in optical manipulation and communication.
- Gallium nitride (GaN) is a promising material for nanophotonics.
Purpose of the Study:
- To experimentally demonstrate highly-efficient geometric and propagation metasurfaces for vortex beam emission.
- To investigate the performance characteristics of GaN-based meta-atoms.
- To compare the wavelength-dependent behavior of geometric and propagation metasurfaces.
Main Methods:
- Fabrication of high-aspect-ratio fin-like and cylindrical GaN meta-atoms.
- Experimental characterization of metasurface efficiency and beam emission.
- Analysis of intensity distribution and wavelength dispersion.
Main Results:
- Achieved up to 99% cross-polarization transmission efficiency with fin-like GaN meta-atoms.
- Demonstrated 97% average co-polarization transmission efficiency with cylindrical GaN meta-atoms.
- Observed annular intensity convergence for vortex beam emission.
- Geometric metasurface exhibited achromatic annular intensity over 100 nm bandwidth, unlike the dispersive propagation metasurface.
Conclusions:
- GaN metasurfaces are highly efficient for generating vortex beams.
- Geometric metasurfaces offer achromatic beam shaping, overcoming limitations of propagation metasurfaces.
- These findings advance the development of advanced optical components for visible light applications.
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