High Efficiency Focusing and Vortex Generator Based on Polarization-Insensitive Gallium Nitride Metasurface

Area of Science:

• Photonics and Nanotechnology
• Materials Science

Background:

• Metasurfaces offer advanced control over light properties.
• Developing polarization-insensitive devices is crucial for versatile optical applications.
• Gallium Nitride (GaN) is a promising material for nanophotonic devices.

Purpose of the Study:

• To propose and demonstrate two novel polarization-insensitive Gallium Nitride (GaN) metasurfaces.
• To achieve dynamic phase control for wavefront manipulation.
• To explore applications in optical communication, holographic projection, and particle capture.

Main Methods:

• Designing metasurfaces with tailored nanoscale structural parameters.
• Utilizing dynamic phase adjustment for wavefront shaping.
• Characterizing metasurface performance under linearly polarized (LP) and circularly polarized (CP) light irradiation.

Main Results:

• One metasurface achieved an 84.7% efficiency in generating a focused beam.
• The second metasurface demonstrated a maximum efficiency of 76.6% for generating a vortex beam.
• Both metasurfaces exhibited polarization-insensitive operation.

Conclusions:

• The proposed GaN metasurfaces provide effective polarization-insensitive wavefront control.
• These devices show significant potential for high-performance optical systems.
• The demonstrated capabilities pave the way for next-generation optical communication and imaging technologies.