Abstract
Closed formulas for upper bounds 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 by Regula et al. [Phys. Rev. Lett. 113, 110501 (2014) and Phys. Rev. Lett. 116, 049902(E) (2016)] to verify monogamy of four-qubit quantum entanglement.
- Received 14 October 2016
DOI:https://doi.org/10.1103/PhysRevA.95.062311
©2017 American Physical Society
Physics Subject Headings (PhySH)
Quantum Information, Science & Technology