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?
TLDR
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
TLDR
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.
Quantitative entanglement witnesses of isotropic and Werner classes via local measurements
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
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 $2\otimes d$
Measurement-device-independent entanglement witnesses for all entangled quantum states.
TLDR
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.
TLDR
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
Design and experimental performance of local entanglement witness operators
TLDR
This work proposes and analyzes a class of entanglement witnesses that detect the presence ofEntanglement in subsystems of experimental multi-qubit stabilizer states and theoretically establishes the noise tolerance of the proposed witnesses and benchmark their practical performance by analyzing the local entangled structure of an experimental seven-qu bit quantum error correction code.
The structure of ultrafine entanglement witnesses
An entanglement witness is an observable with the property that a negative expectation value signals the presence of entanglement. The question arises how a witness can be improved if the expectation
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