Experimental multi-state quantum discrimination through a Quantum network

TL;DR

This paper experimentally demonstrates two quantum state discrimination schemes using a network-based receiver, showing that dynamical processing can achieve optimal results without extra resources, advancing quantum communication techniques.

Contribution

It introduces a novel multi-state quantum discrimination method utilizing a network-like receiver and dynamical features, avoiding additional systems or devices.

Findings

Achieved binary optimal discrimination with a network-based receiver.

Developed a multi-state discrimination approach using arrival time as an encoding variable.

Demonstrated potential of dynamical methods for efficient quantum state discrimination.

Abstract

The need of discriminating between different quantum states is a fundamental issue in Quantum Information and Communication. The actual realization of generally optimal strategies in this task is often limited by the need of supplemental resources and very complex receivers. We have experimentally implemented two discrimination schemes in a minimum-error scenario based on a receiver featured by a network structure and a dynamical processing of information. The first protocol implemented in our experiment, directly inspired to a recent theoretical proposal, achieves binary optimal discrimination, while the second one provides a novel approach to multi-state quantum discrimination, relying on the dynamical features of the network-like receiver. This strategy exploits the arrival time degree of freedom as an encoding variable, achieving optimal results, without the need for supplemental systems or devices. Our results further reveal the potential of dynamical approaches to Quantum State Discrimination tasks, providing a possible starting point for efficient alternatives to current experimental strategies.