Channel discrimination power of bipartite quantum states

Abstract

We quantify the usefulness of a bipartite quantum state in the ancilla-assisted channel discrimination of arbitrary quantum channels, formally defining a worst-case-scenario channel discrimination power for bipartite quantum states. We show that such a quantifier is deeply connected with the operator Schmidt decomposition of the state. We compute the channel discrimination power exactly for pure states, and provide upper and lower bounds for general mixed states. We show that highly entangled states can outperform any state that passes the realignment criterion for separability. Furthermore, while also unentangled states can be used in ancilla-assisted channel discrimination, we show that the channel discrimination power of a state is bounded by its quantum discord.

11 pages, 2 figures, comments welcome

References in corpus (10)

• Necessary and sufficient condition for non-zero quantum discord
• Quantum metrology from a quantum information science perspective
• No-local-broadcasting theorem for quantum correlations
• Quantum Circuits Architecture
• Quantum discord bounds the amount of distributed entanglement
• Quantum cost for sending entanglement
• Bipartite quantum systems: on the realignment criterion and beyond
• Quantumness of correlations, quantumness of ensembles and quantum data hiding
• Additivity and Distinguishability of Random Unitary Channels
• On the relation between Schmidt coefficients and entanglement

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• Unbounded entanglement-sustaining sequential local quantum state discrimination