Postselection-free controlled generation of a high-dimensional orbital-angular-momentum entangled state

TL;DR

This paper introduces a novel, postselection-free method for generating high-dimensional orbital angular momentum entangled states, achieving high control accuracy and enabling advanced quantum information applications.

Contribution

The authors propose and experimentally demonstrate a new technique for generating high-dimensional OAM entangled states without postselection, a significant advancement over previous methods.

Findings

Generated up to 150-dimensional OAM entangled states.

Achieved over 98% control accuracy for Gaussian and triangular spectra.

Reached 90% control accuracy for maximally-entangled rectangular spectra.

Abstract

High-dimensional entangled states in orbital angular momentum (OAM) basis offer several unique advantages for quantum information applications. However, for the optimal performance of a given application, one requires a generation technique for OAM entangled states that is completely postselection-free and fully controllable. Nonetheless, despite several efforts in the past, no such technique currently exists. In this article, we propose just such a technique and experimentally demonstrate postselection-free generation of up to about 150-dimensional OAM entangled states. We report the generation accuracy, which is a measure of the control, to be more than 98% for states with Gaussian and triangular OAM Schmidt spectra and up to 90% for the maximally-entangled OAM states, which have rectangular spectra.