Cylindrical vector beam multiplexing holography employing spin-decoupled phase modulation metasurface

Area of Science:

• Optics and Photonics
• Holography
• Metasurface Technology

Background:

• Cylindrical vector beams (CVBs) are promising for high-capacity information carriers in holography due to mode orthogonality.
• Current CVB holography struggles with independent manipulation of spatial phase and polarization distributions.
• This limitation hinders the full potential of CVBs in advanced holographic applications.

Purpose of the Study:

• To propose a novel spin-decoupled phase modulation strategy for independent control of CVB spatial phase and polarization.
• To demonstrate a metasurface capable of achieving four-channel CVB multiplexing holography.
• To explore the application of composite phase metasurfaces in advanced holographic techniques.

Main Methods:

• Utilizing the propagation and geometric phase of composite phase metasurfaces for spin-decoupled modulation.
• Decomposing CVBs into circularly polarized components on the Poincaré sphere for independent phase control.
• Designing and fabricating a silicon nanopillar metasurface to encode holographic information onto CVBs.

Main Results:

• Achieved independent control over the spatial phase and polarization distributions of CVBs.
• Successfully demonstrated four-channel CVB multiplexing holography with discrete spatial frequencies and opposite helical phases.
• The metasurface operates across the entire visible light spectrum (443 nm-633 nm) due to the non-dispersive geometric phase.

Conclusions:

• The proposed spin-decoupled phase modulation strategy offers comprehensive control over CVB spatial phase and polarization.
• This method significantly advances the application of CVBs in high-capacity multiplexing holography.
• The broad operating bandwidth of the metasurface enhances its practical utility in visible light applications.