High-performance 100 Gbps free-space optical communication via optical pin beam receiver

Free-space optical communication with high transmission bandwidth and small antenna size has been progressively deployed for ground-air-space communications in recent years. However, current mitigation methods, including adaptive optics and transmitter-side beam shaping, are often limited by design complexity and insufficient bandwidth. Here, we propose a receiver-side wavefront correction scheme based on optical pin beam-a ring-shaped, self-healing beam structure-formed via a static phase mask in front of the coupling lens. Unlike traditional optical pin beam methods requiring transmitter-side modulation, our design proactively reshapes the aberrated receiving beam into a stable optical pin beam with extended Rayleigh length, thereby improving mode matching and enhancing coupling resilience under turbulence. In a kilometer-scale outdoor experiment, we demonstrate a 100 Gbps free-space laser link, with coupled power stability increased by 26% and bit error rate decreased by up to 2 orders of magnitude compared with a Gaussian receiver. This receiver-side-only solution simplifies system architecture, ensures high-power compatibility, and offers a low-cost and scalable pathway for future optical ground stations, paving the way for ultra-long-distance, high-speed, and compact Free-space optical communication systems.