Single-Shot Phase Diversity Wavefront Sensing in Deep Turbulence via Metasurface Optics

TL;DR

This paper introduces a compact, low-latency wavefront sensor using metasurface optics for deep turbulence conditions, significantly improving free-space optical communication performance.

Contribution

It presents a novel metasurface-based phase diversity wavefront sensor that operates in deep turbulence with low latency and high effectiveness, demonstrated through simulation and experiments.

Findings

16-fold increase in signal from corrected beam

Effective in mid-to-high turbulence conditions

Enables compact and robust wavefront sensing

Abstract

Free-space optical communication (FSOC) systems offer high-bandwidth and secure communication with minimal capital costs. Adaptive optics (AO) are typically added to these systems to decrease atmospheric channel losses; however, the performance of traditional AO wavefront sensors degrades in long-range, deep turbulence conditions. Alternative wavefront sensors using phase diversity can successfully reconstruct wavefronts in deep turbulence, but current implementations require bulky setups with high latency. In this work, we employ a nanostructured birefringent metasurface optic that enables low-latency phase diversity wavefront sensing in a compact form factor. We prove the effectiveness of this approach in mid-to-high turbulence (Rytov numbers from 0.2 to 0.6) through simulation and experimental demonstration. In both cases an average 16-fold increase in signal from the corrected beam is obtained. Our approach opens a pathway for compact, robust wavefront sensing that enhances range and accuracy of FSOC systems.