2014/06/30 by Avijit Misra, Anindya Biswas, Arun Kumar Pati +4
Computer Science · Mathematics · Physics and Astronomy · #Amplitude damping channel #Generalized relative entropy #Joint quantum entropy #Kullback–Leibler divergence #Mathematics #Physics #Quantum #Quantum Information and Cryptography #Quantum algorithm #Quantum correlation #Quantum discord #Quantum entanglement #Quantum many-body systems #Quantum mechanics #Quantum mutual information #Quantum phase transition #Quantum relative entropy #Statistical Mechanics and Entropy #Statistical physics #Statistics #Von Neumann entropy #cond-mat.str-el #quant-ph
paper · pdf · doi:10.1103/physreve.91.052125
published as Phys. Rev. E 91, 052125 (2015) · 14 pages, 11 figures, RevTeX4.1, Close to published version
openalex publication_date 2015/05/15 · arxiv created 2015/08/06 · arxiv updated 2015/08/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Quantum discord is a measure of quantum correlations beyond the entanglement-separability paradigm. It is conceptualized by using the von Neumann entropy as a measure of disorder. We introduce a class of quantum correlation measures as differences between total and classical correlations, in a shared quantum state, in terms of the sandwiched relative Rényi and Tsallis entropies. We compare our results with those obtained by using the traditional relative entropies. We find that the measures satisfy all the plausible axioms for quantum correlations. We evaluate the measures for shared pure as well as paradigmatic classes of mixed states. We show that the measures can faithfully detect the quantum critical point in the transverse quantum Ising model and find that they can be used to remove an unquieting feature of nearest-neighbor quantum discord in this respect. Furthermore, the measures provide better finite-size scaling exponents of the quantum critical point than the ones for other known order parameters, including entanglement and information-theoretic measures of quantum correlations.