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Dephasing-Covariant Operations Enable Asymptotic Reversibility of Quantum Resources

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 نشر من قبل Eric Chitambar
 تاريخ النشر 2017
  مجال البحث فيزياء
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 تأليف Eric Chitambar




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We study the power of dephasing-covariant operations in the resource theories of coherence and entanglement. These are quantum operations whose actions commute with a projective measurement. In the resource theory of coherence, we find that any two states are asymptotically interconvertible under dephasing-covariant operations. This provides a rare example of a resource theory in which asymptotic reversibility can be attained without needing the maximal set of resource non-generating operations. When extended to the resource theory of entanglement, the resultant operations share similarities with LOCC, such as prohibiting the increase of all Renyi $alpha$-entropies of entanglement under pure state transformations. However, we show these operations are still strong enough to enable asymptotic reversibility between any two maximally correlated mixed states, even in the multipartite setting.

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