6533b85cfe1ef96bd12bca96
RESEARCH PRODUCT
Unifying approach to the quantification of bipartite correlations by Bures distance
Gerardo AdessoMarco CianciarusoMarco CianciarusoRosario Lo FrancoRosario Lo FrancoRosario Lo FrancoThomas R. Bromleysubject
Statistics and ProbabilityQuantum decoherenceSettore FIS/02 - Fisica Teorica Modelli E Metodi MatematiciBures distanceGeneral Physics and AstronomyFOS: Physical sciencesQuantum entanglementSettore FIS/03 - Fisica Della MateriaPhysics and Astronomy (all)classical correlationSubadditivityQuantum systemMathematical PhysicStatistical physicsQuantum informationdecoherenceQuantumMathematical Physicsquantum correlationMathematicsQuantum PhysicsStatistical and Nonlinear PhysicsProbability and statisticsQuantum PhysicsMathematical Physics (math-ph)QubitModeling and SimulationQuantum Physics (quant-ph)Statistical and Nonlinear Physicdescription
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.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2014-01-01 |