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arXiv · 1610.03916

Upper bound on three tangles of reduced states of four-qubit pure states

S. Shelly Sharma·N. K. Sharma
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Abstract

Closed formulae for upper bound on three tangles of three-qubit reduced states in terms of three-qubit invariant polynomials of pure four-qubit states are obtained. Our results offer tighter constraints on total three-way entanglement of a given qubit with the rest of the system than those used in ref. [PRL 113, 110501 (2014), PRL 116, 049902(E) (2016)] to verify monogamy of four-qubit quantum entanglement.

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S. Shelly Sharma, N. K. Sharma. 2017-06-01. Upper bound on three tangles of reduced states of four-qubit pure states. https://doi.org/10.1103/physreva.95.062311

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