Entanglement detection

@inproceedings{Guhne2008EntanglementD,
  title={Entanglement detection},
  author={Otfried Guhne and G{\'e}za T{\'o}th},
  year={2008}
}

What Criterion Can We Get From Precise Entanglement Witnesses?

A thorough study of a three-qubit Greenberger-Horne-Zeilinger (GHZ) state mixed with a W state and white noise finds a connection between Wootters formula and the matched entanglement witness.

Detecting entanglement of unknown quantum states with random measurements

This work investigates the use of random local measurements, from which entanglement witnesses are then constructed via semidefinite programming methods, and proposes a scheme of successively increasing the number of measurements until the presence ofEntanglement can be unambiguously concluded.

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Quantitative entanglement witnesses allow one to bound the entanglement present in a system by acquiring a single expectation value. In this paper, we analyze a special class of such observables

Minimal Entanglement Witness from Electrical Current Correlations.

It is found that all entangled pure states, but not all mixed ones, can be detected with only two measurements, except the maximally entangled states, which require three measurements.

Nonlinear improvement of qubit-qudit entanglement witnesses

The entanglement witness is an important and experimentally applicable tool for entanglement detection. In this paper, we provide a nonlinear improvement of any entanglement witness for $2\otimes d$

Entanglement Detection by Violations of Noisy Uncertainty Relations: A Proof of Principle.

This proof-of-principle experiment shows that quantum noise can be successfully handled by a fully quantum model in order to enhance the ability to detect entanglement.

Measurement-device-independent entanglement witnesses for all entangled quantum states.

This work introduces the concept of measurement-device-independent entanglement witnesses (MDI-EWs), which allow one to demonstrateEntanglement of all entangled quantum states with untrusted measurement apparatuses, and shows how to systematically obtain such MDI-ews from standard entangler witnesses.

Geometry of Faithful Entanglement.

This work proves a structural result on the corresponding fidelity-based entanglement witnesses, resulting in a simple condition for faithfulness of a two-party state, and shows that faithful Entanglement is, in a certain sense, usefulEntanglement theory.

Device-Independent Entanglement Detection

Entanglement is one of the most intriguing feature of quantum physics. It allows several particles to be in a state which cannot be understood as a concatenation of the sate of each particle.

Device-Independent Entanglement Certification of All Entangled States.

We present a method to certify the entanglement of all entangled quantum states in a device-independent way. This is achieved by placing the state in a quantum network and constructing a correlation
...

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