title: Compressibility of quantum mixed-state signals.
abstract: We present a formula that determines the optimal number of qubits per message that allows asymptotically faithful compression of the quantum information carried by an ensemble of mixed states. The set of mixed states determines a decomposition of the Hilbert space into the redundant part and the irreducible part. After removing the redundancy, the optimal compression rate is shown to be given by the von Neumann entropy of the reduced ensemble.
authors.affiliation: CREST Research Team for Interacting Carrier Electronics, School of Advanced Sciences, The Graduate University for Advanced Studies (SOKEN), Hayama, Kanagawa 240-0193, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Koashi
authors.forename: N
authors.initials: N
authors.lastname: Imoto