Entanglement enhanced distinguishability of coherence-breaking channels

Abstract

Originating from the superposition principle in quantum mechanics, coherence has been extensively studied as a kind of 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 it cannot be enhanced for some other cases. For coherence-breaking channels with different types, the channel distinguishability cannot be enhanced via entanglement.