Entanglement detection

@inproceedings{Guhne2008EntanglementD,
  title={Entanglement detection},
  author={Otfried Guhne and G{\'e}za T{\'o}th},
  year={2008}
}
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1,370 Citations
Highly Influential Citations
56
Background Citations
346
Methods Citations
85
Results Citations
1

1,370 Citations

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References

SHOWING 1-10 OF 540 REFERENCES

Estimating entanglement measures in experiments.

It is shown how a lower bound on a genericEntanglement measure can be derived from the measured expectation values of any finite collection of entanglement witnesses, and witness measurements are given a quantitative meaning without the need of further experimental data.

Experimental detection of entanglement via witness operators and local measurements

Abstract In this paper we address the problem of detection of entanglement using only few local measurements when some knowledge about the state is given. The idea is based on an optimized…

Measuring quantum entanglement without prior state reconstruction.

It is shown that, despite strong nonlinearity, entanglement of formation of a two-qubit state can be measured without prior state reconstruction. Collective measurements on a small number of copies…

Characterizing Entanglement

Quantum entanglement is at the heart of many tasks in quantum information. Apart from simple cases (low dimensions, few particles, pure states), however, the mathematical structure of entanglement is…

Quantitative entanglement witnesses

All these tests—based on the very same data—give rise to quantitative estimates in terms of entanglement measures, and if a test is strongly violated, one can also infer that the state was quantitatively very much entangled, in the bipartite and multipartite setting.

Characterizing entanglement with geometric entanglement witnesses

We show how to detect entangled, bound entangled and separable bipartite quantum states of arbitrary dimension and mixedness using geometric entanglement witnesses. These witnesses are constructed…

Geometric entanglement witnesses and bound entanglement

We study entanglement witnesses that can be constructed with regard to the geometrical structure of the Hilbert-Schmidt space, i.e., we present how to use these witnesses in the context of…

Entanglement detection by local orthogonal observables.

A family of entanglement witnesses and corresponding positive maps that are not completely positive based on local orthogonal observables that can be physically realized by measuring a Hermitian correlation matrix of local orthosomatic observables.

Novel schemes for directly measuring entanglement of general states.

It is demonstrated that rank-1 local factorizable projective measurements, which are achievable with only one copy of an entangled state involved at a time in a sequential way, are sufficient to directly determine the concurrence of an arbitrary two-qubit entangled state.

Detecting quantum entanglement : entanglement witnesses and uncertainty relations

This thesis deals with methods of the detection of entanglement. After recalling some facts and definitions concerning entanglement and separability, we investigate two methods of the detection of…
...