Experimental certification of high-dimensional entanglement with randomized measurements

TL;DR

This paper demonstrates an experimental method to certify high-dimensional entanglement using randomized measurements, which is robust against phase randomization and does not require a shared reference frame, enhancing quantum communication capabilities.

Contribution

The authors experimentally certify three-dimensional entanglement in a five-dimensional system using Haar-random measurements, showcasing robustness against random rotations and phase noise.

Findings

Successfully certified high-dimensional entanglement with 800 measurements

Demonstrated robustness against arbitrary phase randomization

Method does not require a shared reference frame between parties

Abstract

High-dimensional entangled states offer higher information capacity and stronger resilience to noise compared with two-dimensional systems. However, the large number of modes and sensitivity to random rotations complicate experimental entanglement certification. Here, we experimentally certify three-dimensional entanglement in a five-dimensional two-photon state using 800 Haar-random measurements implemented via a 10-plane programmable light converter. We further demonstrate the robustness of this approach against random rotations, certifying high-dimensional entanglement despite arbitrary phase randomization of the optical modes. This method, which requires no common reference frame between parties, opens the door for high-dimensional entanglement distribution through long-range random links.