Cylindrical vector beams demultiplexing optical communication based on spin-dependent vortex Dammann grating

Appl Opt. 2020 Dec 10;59(35):11041-11045. doi: 10.1364/AO.409641.

Abstract

The amount of information is increasing rapidly to reach the capacity limit of single mode fiber. Cylindrical vector beams (CVBs) as the eigenmodes of fiber have been demonstrated to increase the capacity in multiplexing optical communication. As a key component of CVB multiplexing, a sorter based on spin-dependent vortex Dammann grating has advantages of uniform power distribution and compact size. Here, we propose and demonstrate a spin-dependent vortex Dammann grating device that can realize the sorting of multiple CVBs. By a spin-dependent focusing lens, the spin components of the CVBs are selectively focused or derived; therefore, the coaxially incident CVBs are separated effectively. We also experimentally demonstrate the CVB demultiplexing communication enabled by the grating with low channel cross talk satisfying the communication requirement.