High-order OAM states unwrapping in multiplexed optical links

To accurately unwrap the high-order orbital angular momentum (OAM) for multiplexed vortex beams is a challenge. In this work, over +/- 160 order OAM topological charges have been unwrapped in multiplexed optical links. Optical imaging based discrepancy identification enables the multiplexed OAM modes separating in physics, and the intelligent pattern recognition further promotes its unwrapping in numerical domain. Particularly, the combination of annular phase grating and auxiliary beams features compound spiral stripes, which paves the way for optical intensity recognition with low-complexity and high-commonality. Moreover, the spiral direction characterizes the symbol of the OAM states, which dramatically broadens the amount of multiplexed links. Here, optical separating means assisted by intelligent pattern recognition opens up a new route to high-speed and large-capacity optical communication, which may shed new light on 6G application. (C) 2023 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). https://doi.org/10.1063/5.0144999

Automated summary

In this work, the challenge of accurately unwrapping high-order orbital angular momentum (OAM) for multiplexed vortex beams is addressed. By utilizing optical imaging and intelligent pattern recognition, the OAM modes are separated and unwrapped successfully in the numerical domain. The combination of annular phase grating and auxiliary beams enables low-complexity and high-commonality optical intensity recognition, while the spiral direction characterizes the OAM states' symbol, significantly increasing the number of multiplexed links. The optical separating means assisted by intelligent pattern recognition opens up a new route for high-speed and large-capacity optical communication, with potential implications for 6G applications.