Tight lower bound to the geometric measure of quantum discord
arXiv:1010.1920 · doi:10.1103/PhysRevA.85.024302
Abstract
Dakic, Vedral and Brukner [Physical Review Letters \tf{105},190502 (2010)] gave a geometric measure of quantum discord in a bipartite quantum state as the distance of the state from the closest classical quantum (or zero discord) state and derived an explicit formula for a two qubit state. Further, S.Luo and S.Fu [Physical Review A \tf{82}, 034302 (2010)] obtained a generic form of this geometric measure for a general bipartite state and established a lower bound. In this brief report we obtain a rigorous lower bound to the geometric measure of quantum discord in a general bipartite state which dominates that obtained by S.Luo and S.Fu.
10 pages,2 figures. In the previous versions, a constraint was ignored while optimizing the second term in Eq.(5), in which case, only a lower bound on the geometric discord can be obtained. The title is also consequently changed. Accepted in Phys.Rev.A
References in corpus (12)
- Quantum discord and the power of one qubit
- Necessary and sufficient condition for non-zero quantum discord
- Experimental quantum computing without entanglement
- Robustness of quantum discord to sudden death
- Quantum discord and quantum phase transition in spin chains
- Vanishing quantum discord is necessary and sufficient for completely positive maps
- On the role of entanglement and correlations in mixed-state quantum computation
- Quantum Discord and the Geometry of Bell-Diagonal States
- Monogamy properties of quantum and classical correlations
- Quantum discord and local demons
- Quantum correlation and classical correlation dynamics in the spin-boson model
- An Experimentally accessible geometric measure for entanglement in -qubit pure states
Cited by in corpus (36)
- The classical-quantum boundary for correlations: discord and related measures
- Measures and applications of quantum correlations
- Quantum coherence and geometric quantum discord
- Geometric quantum discord through the Schatten 1-norm
- Quantum discord and its allies: a review
- One-norm geometric quantum discord under decoherence
- Geometric classical and total correlations via trace distance
- Evolution of Quantum Discord and its Stability in Two-Qubit NMR Systems
- On two-qubit states ordering with quantum discords
- Signatures of bifurcation on quantum correlations: Case of the quantum kicked top
- Calculation of quantum discord in arbitrary dimensions, especially for X- and other specialized states
- Geometric discord and Measurement-induced nonlocality for well known bound entangled states
- Progress towards a unified approach to entanglement distribution
- Quantum correlation via quantum coherence
- Local Quantum Uncertainty and Bounds on Quantumness for Orthogonally invariant class of states
- Geometric global quantum discord of two-qubit X states
- Quantum discord in quantum random access codes and its connection with dimension witness
- Geometric global quantum discord
- Quantum and classical correlations in high temperature dynamics of two coupled large spins
- Quantum correlations in qutrit-qutrit systems under local quantum noise channels
- Computable measure of the quantum correlation
- Maximally discordant separable two qubit states
- Measurement - induced qudit geometric discord
- Quantum Discord for Generalized Bloch Sphere States
- Geometric measure of quantum discord and the geometry of a class of two-qubit states
- Geometric quantum discord of an arbitrary two-qudit state: the exact value and general upper bounds
- A recursive approach for geometric quantifiers of quantum correlations in multiqubit Schrödinger cat states
- Computing coherence vectors and correlation matrices, with application to quantum discord quantification
- Quantum correlations and coherence between two particles interacting with a thermal bath
- The Geometric Structure of Quantum Resources for Bell-diagonal states
- Bath-induced correlations in an infinite-dimensional Hilbert space
- Quantum Correlations in NMR systems
- Multipartite Generalization of Geometric measure of Discord
- Comment on "Sudden change in quantum discord accompanying the transition from bound to free entanglement"
- Correlation and Entanglement dynamics for two atoms distributed in two isolated thermal cavities
- Computable Measure of Total Quantum Correlation of Multipartite Systems