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Thermal States as Convex Combinations of Matrix Product States

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 نشر من قبل Mario Berta
 تاريخ النشر 2017
  مجال البحث فيزياء
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We study thermal states of strongly interacting quantum spin chains and prove that those can be represented in terms of convex combinations of matrix product states. Apart from revealing new features of the entanglement structure of Gibbs states our results provide a theoretical justification for the use of Whites algorithm of minimally entangled typical thermal states. Furthermore, we shed new light on time dependent matrix product state algorithms which yield hydrodynamical descriptions of the underlying dynamics.

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