TY - JOUR

T1 - Unifying approach to the quantification of bipartite correlations by Bures distance

AU - Lo Franco, Rosario

AU - Cianciaruso, Marco

AU - Bromley, Thomas R.

AU - Adesso, Gerardo

AU - Franco, Rosario Lo

PY - 2014

Y1 - 2014

N2 - The notion of distance defined on the set of states of a composite quantum system can be used to quantify total, quantum and classical correlations in a unifying way. We provide new closed formulae for classical and total correlations of two-qubit Bell-diagonal states by considering the Bures distance. Complementing the known corresponding expressions for entanglement and more general quantum correlations, we thus complete the quantitative hierarchy of Bures correlations for Bell-diagonal states. We then explicitly calculate Bures correlations for two relevant families of states: Werner states and rank-2 Bell-diagonal states, highlighting the subadditivity which holds for total correlations with respect to the sum of classical and quantum ones when using Bures distance. Finally, we analyse a dynamical model of two independent qubits locally exposed to non-dissipative decoherence channels, where both quantum and classical correlations measured by Bures distance exhibit freezing phenomena, in analogy with other known quantifiers of correlations.

AB - The notion of distance defined on the set of states of a composite quantum system can be used to quantify total, quantum and classical correlations in a unifying way. We provide new closed formulae for classical and total correlations of two-qubit Bell-diagonal states by considering the Bures distance. Complementing the known corresponding expressions for entanglement and more general quantum correlations, we thus complete the quantitative hierarchy of Bures correlations for Bell-diagonal states. We then explicitly calculate Bures correlations for two relevant families of states: Werner states and rank-2 Bell-diagonal states, highlighting the subadditivity which holds for total correlations with respect to the sum of classical and quantum ones when using Bures distance. Finally, we analyse a dynamical model of two independent qubits locally exposed to non-dissipative decoherence channels, where both quantum and classical correlations measured by Bures distance exhibit freezing phenomena, in analogy with other known quantifiers of correlations.

KW - Bures distance

KW - Mathematical Physics

KW - Modeling and Simulation

KW - Physics and Astronomy (all)

KW - Statistical and Nonlinear Physics

KW - Statistics and Probability

KW - classical correlations

KW - decoherence

KW - quantum correlations

KW - Bures distance

KW - Mathematical Physics

KW - Modeling and Simulation

KW - Physics and Astronomy (all)

KW - Statistical and Nonlinear Physics

KW - Statistics and Probability

KW - classical correlations

KW - decoherence

KW - quantum correlations

UR - http://hdl.handle.net/10447/130500

UR - http://iopscience.iop.org/1751-8121/47/40/405302/pdf/1751-8121_47_40_405302.pdf

M3 - Article

VL - 47

SP - 405302-

JO - Journal of Physics A: Mathematical and Theoretical

JF - Journal of Physics A: Mathematical and Theoretical

SN - 1751-8113

ER -