# Entanglement Quantification in Atomic Ensembles.

@article{Fadel2021EntanglementQI, title={Entanglement Quantification in Atomic Ensembles.}, author={Matteo Fadel and Ayaka Usui and Marcus Huber and Nicolai Friis and Giuseppe Vitagliano}, journal={Physical review letters}, year={2021}, volume={127 1}, pages={ 010401 } }

Entanglement measures quantify nonclassical correlations present in a quantum system, but can be extremely difficult to calculate, even more so, when information on its state is limited. Here, we consider broad families of entanglement criteria that are based on variances of arbitrary operators and analytically derive the lower bounds these criteria provide for two relevant entanglement measures: the best separable approximation and the generalized robustness. This yields a practical method for…

## 5 Citations

A Necessary and Sufficient Entanglement Criterion of N-qubit System Based on Correlation Tensor

- Physics, Education
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Great advances have been achieved in studying characteristics of entanglement for fundamentals of quantum mechanics and quantum information processing. However, even for N -qubit systems, the problem…

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- Physics
- 2022

Matteo Fadel, 2, ∗ Benjamin Yadin, Yuping Mao, Tim Byrnes, 4, 6, 7, 8 and Manuel Gessner † Department of Physics, ETH Zürich, 8093 Zürich, Switzerland Department of Physics, University of Basel,…

Entanglement of Local Hidden States

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Steering criteria are conditions whose violation excludes the possibility of describing the observed measurement statistics with local hidden state (LHS) models. When the available data do not allow…

Quantum Correlations: Experiments

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- 2021

Universal separability criterion for arbitrary density matrices from causal properties of separable and entangled quantum states

- Materials ScienceScientific reports
- 2021

Brand new general relations for the heuristic causal separability criterion have been proposed for arbitrary EC-density matrices and are shown to be applicable to a wide range of both interacting and non-interacting quantum systems.

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