# Degenerate cavity supporting more than 31 Laguerre-Gaussian modes

## TL;DR

This paper demonstrates an experimental ring cavity capable of supporting over 31 Laguerre-Gaussian modes, enabling advanced applications in optical communication and quantum information by utilizing multiple orbital angular momentum states simultaneously.

## Contribution

The work constructs a fully degenerate ring cavity supporting more than 31 Laguerre-Gaussian modes, a significant increase in mode capacity for optical systems.

## Key findings

- Supports over 31 Laguerre-Gaussian modes
- Supports high-capacity optical communication
- Enables quantum information processing applications

## Abstract

Photons propagating in Laguerre-Gaussian modes have characteristic orbital angular momentums, which are fundamental optical degrees of freedom. The orbital angular momentum of light has potential application in high capacity optical communication and even in quantum information processing. In this work, we experimentally construct a ring cavity with 4 lenses and 4 mirrors that is completely degenerate for Laguerre-Gaussian modes. By measuring the transmission peaks and patterns of different modes, the ring cavity is shown to supporting more than 31 Laguerre-Gaussian modes. The constructed degenerate cavity opens a new way for using the unlimited resource of available angular momentum states simultaneously.