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Separable balls around the maximally mixed state for a 3-qubit system

Roland Hildebrand
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Abstract

We obtain a new lower bound on the radius of the largest ball of separable unnormalized states around the identity matrix for a 3-qubit system. This also enables us to improve the corresponding lower bounds for multi-qubit systems. These bounds are approximately 5% better than the previously known ones. As a by-product, we compute the radius of the largest ball that fits into the triple projective tensor product of the unit ball in R^3.

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Roland Hildebrand. 2006-01-30. Separable balls around the maximally mixed state for a 3-qubit system. https://arxiv.org/abs/quant-ph/0601201

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