Structured Beam Generation with a Single Metasurface

TL;DR

This paper introduces a novel method to generate vector vortex beams using a single metasurface, enabling high-efficiency, compact, and versatile optical wave engineering for various applications.

Contribution

The paper presents a new approach to produce vector vortex beams with a single metasurface by locally controlling phase and polarization, improving efficiency and reducing size.

Findings

Successfully generated cylindrically polarized vortex beams with a single metasurface

Achieved high-efficiency light utilization and minimal footprint

Demonstrated control over optical wave properties through spin-orbit coupling

Abstract

Despite a plethora of applications ranging from quantum memories to high-resolution lithography, the current technologies to generate vector vortex beams (VVBs) suffer from less efficient energy use, poor resolution, low damage threshold, bulky size and complicated experimental setup, preventing further practical applications. We propose and experimentally demonstrate an approach to generate VVBs with a single metasurface by locally tailoring phase and transverse polarization distribution. This method features the spin-orbit coupling and the superposition of the converted part with an additional phase pickup and the residual part without a phase change. By maintaining the equal components for the converted part and the residual part, the cylindrically polarized vortex beams carrying orbital angular momentum are experimentally demonstrated based on a single metasurface at subwavelength scale. The proposed approach provides unprecedented freedom in engineering the properties of optical waves with the high-efficiency light utilization and a minimal footprint.