Asymptotically perfect discrimination in the LOCC paradigm

TL;DR

This paper investigates the limits of asymptotic quantum state discrimination using LOCC, establishing necessary conditions for perfect discrimination and analyzing the advantages of unlimited resources.

Contribution

It provides a necessary condition for asymptotic perfect LOCC discrimination and examines the impact of unlimited resources on discriminating product bases.

Findings

Unlimited resources do not improve discrimination for complete product bases.

A specific example remains unresolved regarding the benefit of unlimited resources.

Necessary condition for perfect asymptotic LOCC discrimination is established.

Abstract

We revisit the problem of discriminating orthogonal quantum states within the local quantum operation and classical communication (LOCC) paradigm. Our particular focus is on the asymptotic situation where the parties have infinite resources and the protocol may become arbitrarily long. Our main result is a necessary condition for perfect asymptotic LOCC discrimination. As an application, we prove that for complete product bases, unlimited resources are of no advantage. On the other hand, we identify an example, for which it still remains undecided whether unlimited resources are superior.