Are all maximally entangled states pure

@article{Cavalcanti2005AreAM,
  title={Are all maximally entangled states pure},
  author={Daniel Cavalcanti and Fernando G. S. L. Brand{\~a}o and Marcelo O. Terra Cunha},
  journal={Physical Review A},
  year={2005},
  volume={72},
  pages={040303}
}
We study if all maximally entangled states are pure through several entanglement monotones. In the bipartite case, we find that the same conditions which lead to the uniqueness of the entropy of entanglement as a measure of entanglement exclude the existence of maximally mixed entangled states. In the multipartite scenario, our conclusions allow us to generalize the idea of the monogamy of entanglement: we establish the polygamy of entanglement, expressing that if a general state is maximally… 

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