High-dimensional Orbital Angular Momentum Communication of Perfect Vortex Beam Based on Demultiplexing of Microlens Array with sector sub-aperture

Abstract

The Perfect Vortex Beam (PVB) exhibits a consistent ring radius across different Orbital Angular Momentum (OAM) modes, this unique characteristic endows the PVB has excellent application prospects in the free-space optical communication field, etc. In this paper, we experimentally demonstrate a high-dimensional OAM communication method using PVB for encoding, and demultiplexing via a microlens array with sector sub-aperture(MLA-S). At the transmitter, multiple PVB with different radii and modes are superimposed to achieve high-dimensional information encoding. At the receiver, an MLA-S is employed for decoding, which the circularly symmetric structure effectively matches the helical phase. This device can simultaneously measure multiple OAM modes at different spatial positions. And compared to using only the OAM modulation, this method can encode more information by utilizing fewer modes. Meanwhile, the OAM decoding device has high measurement accuracy, and a large measurement range without complex image processing. Therefore, this work has promising applications in high-capacity spatial optical communication and mode recognition.