Witnessed Entanglement

  title={Witnessed Entanglement},
  author={Fernando G. S. L. Brand{\~a}o and Reinaldo O. Vianna},
We present a new measure of entanglement for mixed states. It can be approximately computable for every state and can be used to quantify all different types of multipartite entanglement. We show that it satisfies the usual properties of a good entanglement quantifier and derive relations between it and other entanglement measures. 
Entanglement witnesses generated by positive maps
  • Wei Yang
  • Physics
    Quantum Inf. Process.
  • 2015
Positive maps based on one and two given quantum states are constructed, and entanglement witnesses are generated by composing the positive maps with affine maps.
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