Compact sorting of optical vortices by means of diffractive transformation optics

TL;DR

This paper introduces a compact, efficient diffractive optical element for demultiplexing optical vortices based on optical transformations, enhancing OAM-based communication systems.

Contribution

It presents the design, fabrication, and characterization of a novel diffractive optical element for OAM mode division demultiplexing using transformation optics.

Findings

High efficiency in OAM mode separation

Compact design suitable for integration

Successful fabrication with electron beam lithography

Abstract

The orbital angular momentum (OAM) of light has recently attracted a growing interest as a new degree of freedom in order to increase the information capacity of today optical networks both for free-space and optical fiber transmission. Here we present our work of design, fabrication and optical characterization of diffractive optical elements for compact OAM-mode division demultiplexing based on optical transformations. Samples have been fabricated with 3D high-resolution electron beam lithography on polymethylmethacrylate (PMMA) resist layer spun over a glass substrate. Their high compactness and efficiency make these optical devices promising for integration into next-generation platforms for OAM-modes processing in telecom applications.