# A Hybrid Metadetector for Measuring Bell States of Optical Angular Momentum Entanglement

## TL;DR

This paper introduces a new hybrid metadetector for measuring entangled optical angular momentum states, which could advance quantum communication and on-chip quantum devices.

## Contribution

A novel hybrid metadetector combining TMDs and spin Hall nanoantennas for Bell state detection of optical angular momentum is proposed.

## Key findings

- Bell states of optical angular momentum are effectively identified using the hybrid metadetector.
- The metadetector converts states into path-entangled polaritonic modes for detection.
- TMDs are shown to be a promising platform for integrated quantum circuits.

## Abstract

High-dimensional entanglement of optical angular momentum has shown its enormous potential for increasing robustness and data capacity in quantum communication and information multiplexing, thus offering promising perspectives for quantum information science. To make better use of optical angular momentum entangled states, it is necessary to develop a reliable platform for measuring and analyzing them. Here, we propose a hybrid metadetector of monolayer transition metal dichalcogenide (TMD) integrated with spin Hall nanoantenna arrays for identifying Bell states of optical angular momentum. The corresponding states are converted into path-entangled states of propagative polaritonic modes for detection. Several Bell states in different forms are shown to be identified effectively. TMDs have emerged as an attractive platform for the next generation of on-chip optoelectronic devices. Our work may open up a new horizon for devising integrated quantum circuits based on these two-dimensional van der Waals materials.