Estimating entanglement of unknown states

@article{Cavalcanti2006EstimatingEO,
title={Estimating entanglement of unknown states},
author={Daniel Cavalcanti and Marcelo O. Terra Cunha},
journal={Applied Physics Letters},
year={2006},
volume={89},
pages={084102}
}
• Published 17 May 2006
• Physics
• Applied Physics Letters
The experimental determination of entanglement is a major goal in the quantum information field. In general, the knowledge of the state is required in order to quantify its entanglement. Here we express a lower bound to the robustness of entanglement of a state based only on the measurement of the energy observable and on the calculation of a separability energy. This allows the estimation of entanglement dismissing the knowledge of the state in question.
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