Dimension witnesses and quantum state discrimination

TL;DR

This paper introduces simple, general dimension witnesses for quantum systems of any Hilbert space dimension, linking them to quantum state discrimination and enabling device-independent testing of quantum versus classical systems.

Contribution

It presents a novel approach connecting dimension witnesses with quantum state discrimination, applicable to arbitrary Hilbert space dimensions, and capable of distinguishing classical from quantum systems.

Findings

Dimension witnesses for arbitrary quantum system dimensions

Strong link established between dimension witnesses and quantum state discrimination

Potential applications in quantum information processing

Abstract

Dimension witnesses allow one to test the dimension of an unknown physical system in a device-independent manner, that is, without placing assumptions about the functioning of the devices used in the experiment. Here we present simple and general dimension witnesses for quantum systems of arbitrary Hilbert space dimension. Our approach is deeply connected to the problem of quantum state discrimination, hence establishing a strong link between these two research topics. Finally, our dimension witnesses can distinguish between classical and quantum systems of the same dimension, making them potentially useful for quantum information processing.