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arXiv · 0805.0619

Uncertainty inequalities as entanglement criteria for negative partial-transpose states

Hyunchul Nha·M. Suhail Zubairy
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Abstract

In this Letter, we show that the fulfillment of uncertainty relations is a sufficient criterion for a quantum-mechanically permissible state. We specifically construct two pseudo-spin observables for an arbitrary non-positive Hermitian matrix whose uncertainty relation is violated. This method enables us to systematically derive separability conditions for all negative partial-transpose states in experimentally accessible forms. In particular, generalized entanglement criteria are derived from the Schrodinger-Robertson inequalities for bipartite continuous-variable states.

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Hyunchul Nha, M. Suhail Zubairy. 2008-09-27. Uncertainty inequalities as entanglement criteria for negative partial-transpose states. https://doi.org/10.1103/physrevlett.101.130402

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