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arXiv · 1812.00752

Sharma-Mittal Quantum Discord

Souma Mazumdar·Supriyo Dutta·Partha Guha
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Abstract

We demonstrate a generalization of quantum discord using a generalized definition of von-Neumann entropy, which is Sharma-Mittal entropy; and the new definition of discord is called Sharma-Mittal quantum discord. Its analytic expressions are worked out for two qubit quantum states as well as Werner, isotropic, and pointer states as special cases. The R{é}nyi, Tsallis, and von-Neumann entropy based quantum discords can be expressed as limiting cases for of Sharma-Mittal quantum discord. We also numerically compare all these discords and entanglement negativity.

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Souma Mazumdar, Supriyo Dutta, Partha Guha. 2019-05-15. Sharma-Mittal Quantum Discord. https://doi.org/10.1007/s11128-019-2289-3

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