# 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} }

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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