arXiv:1711.02323 · Physical Review A

Characterizing nonclassical correlations via local quantum Fisher information

Sunho Kim, Longsuo Li, Asutosh Kumar, Junde Wu

Published Mar 19, 2018• 102 citations

Abstract

We define two ways of quantifying the quantum correlations based on quantum Fisher information (QFI) in order to study the quantum correlations as a resource in quantum metrology. By investigating the hierarchy of measurement-induced Fisher information introduced in Lu et al. [X. M. Lu, S. Luo, and C. H. Oh, Phys. Rev. A 86, 022342 (2012)], we show that the presence of quantum correlation can be confirmed by the difference of the Fisher information induced by the measurements of two hierarchies. In particular, the quantitative quantum correlations based on QFI coincide with the geometric discord for pure quantum states.

DOI: 10.1103/physreva.97.032326

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