Entanglement enhanced distinguishability of coherence-breaking channels

TL;DR

This paper explores how quantum entanglement can improve the ability to distinguish certain coherence-breaking channels, revealing that entanglement's effectiveness varies depending on channel types.

Contribution

It provides explicit calculations showing when entanglement enhances channel distinguishability and when it does not, clarifying the role of entanglement in quantum channel discrimination.

Findings

Entanglement can enhance distinguishability for some coherence-breaking channels.

Entanglement does not improve distinguishability for channels of different types.

The effectiveness of entanglement depends on the specific channel properties.

Abstract

Originated from the superposition principle in quantum mechanics, coherence has been extensively studied as a kind important resource in quantum information processing. We investigate the distinguishability of coherence-breaking channels with the help of quantum entanglement. By explicitly computing the minimal error probability of channel discrimination, it is shown that entanglement can enhance the capacity of coherence-breaking channel distinguishability with same types for some cases while cannot enhanced for some other cases. For coherence-breaking channels with different types, the channel distinguishability cannot be enhanced via entanglement.