Comment on "Quantum discord through the generalized entropy in bipartite quantum states"
arXiv:1504.02046 · doi:10.1140/epjd/e2014-50474-x
Abstract
In [X.-W. Hou, Z.-P. Huang, S. Chen, Eur. Phys. J. D 68, 1 (2014)], Hou et al. present, using Tsallis' entropy, possible generalizations of the quantum discord measure, finding original results. As for the mutual informations and discord, we show here that these two types of quantifiers can take negative values. In the two qubits instance we further determine in which regions they are non-negative. Additionally, we study alternative generalizations on the basis of Rényi entropies.
arXiv comment5 pages, 4 figures
References in corpus (8)
- Introducing Quantum Discord
- On quantum Renyi entropies: a new generalization and some properties
- Strong converse for the classical capacity of entanglement-breaking and Hadamard channels via a sandwiched Renyi relative entropy
- A Fully Quantum Asymptotic Equipartition Property
- Measuring Gaussian quantum information and correlations using the Renyi entropy of order 2
- Monotonicity of a relative Rényi entropy
- Information theoretical properties of Tsallis entropies
- Subadditivity of q-entropies for q>1