The emergence of cylindrical vector beam (CVB) multiplexing has opened new avenues for high-capacity optical communication. Although several configurations have been developed to couple/separate CVBs, the CVB multiplexer/demultiplexer remains elusive due to lack of effective off-axis polarization control technologies. Here we report a straightforward approach to realize off-axis polarization control for CVB multiplexing/demultiplexing based on a metal–dielectric–metal metasurface. We show that the left- and right-handed circularly polarized (LHCP/RHCP) components of CVBs are independently modulated via spin-to-orbit interactions by the properly designed metasurface, and then simultaneously multiplexed and demultiplexed due to the reversibility of light path and the conservation of vector mode. We also show that the proposed multiplexers/demultiplexers are broadband (from 1310 to 1625 nm) and compatible with wavelength-division-multiplexing. As a proof of concept, we successfully demonstrate a four-channel CVB multiplexing communication, combining wavelength-division-multiplexing and polarization-division-multiplexing with a transmission rate of 1.56 Tbit/s and a bit-error-rate of 10⁻⁶ at the receive power of −21.6 dBm. This study paves the way for CVB multiplexing/demultiplexing and may benefit high-capacity CVB communication.

圆柱矢量光束（CVB）复用的出现为高容量光通信开辟了新途径。尽管已经开发出多种配置来耦合/分离 CVB，但由于缺乏有效的离轴偏振控制技术，CVB 复用器/解复用器仍然难以捉摸。在这里，我们报告了一种基于金属-电介质-金属超表面实现 CVB 复用/解复用的离轴偏振控制的简单方法。我们表明，CVB 的左旋和右旋圆偏振 (LHCP/RHCP) 分量通过正确设计的超表面的自旋到轨道相互作用进行独立调制，然后由于光路的可逆性而同时进行复用和解复用。向量模式守恒。我们还表明，所提出的复用器/解复用器是宽带的（从 1310 到 1625 nm）并且与波分复用兼容。作为概念验证，我们成功演示了四通道 CVB 复用通信，结合了波分复用和偏振复用，传输速率为 1.56 Tbit/s，误码率为 10 ⁻⁶接收功率为−21.6 dBm。这项研究为 CVB 复用/解复用铺平了道路，并可能有益于大容量 CVB 通信。