Robust certification of high-dimensional quantum devices

TL;DR

This paper introduces and experimentally demonstrates a robust protocol for certifying high-dimensional quantum behavior between distant parties without preshared resources, using single-photon orbital angular momentum states.

Contribution

The authors develop and validate a scalable, noise-tolerant certification protocol for high-dimensional quantum systems in prepare-and-measure scenarios, avoiding entanglement or measurement incompatibility.

Findings

Successfully certified non-classicality in high-dimensional states with noise robustness

Implemented the protocol using orbital angular momentum of single photons

Demonstrated practical validation of high-dimensional quantum communication

Abstract

Certifying quantum behavior from classically accessible data is essential for secure communication and scalable quantum technologies. While powerful certification methods such as Bell nonlocality and quantum steering exist, their implementation typically requires entanglement or additional assumptions, and experimental demonstrations mainly focus on low-dimensional systems. In minimal prepare-and-measure scenarios, where a sender encodes information into quantum states and a receiver performs a single measurement, robust certification becomes particularly challenging, especially in the presence of noise and in higher-dimensional Hilbert spaces. Here, we propose, design, and experimentally implement a protocol that certifies quantumness between two distant parties without the need for preshared resources or measurement incompatibility. The experiments are carried out using the orbital angular momentum degrees of freedom of single photons, chosen for providing increased dimensionality that is scalable. We demonstrate the robustness of the protocol through rank-stability analysis of the observed correlations, which enables the certification of non-classicality even in the presence of noise. Our results provide a practical route to validate high-dimensional quantum communication systems and open new possibilities for secure and dimension-efficient quantum information processing.