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Exponentially long lifetime of universal quasi-steady states in topological Floquet pumps

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 نشر من قبل Tobias Gulden
 تاريخ النشر 2019
  مجال البحث فيزياء
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We investigate a mechanism to transiently stabilize topological phenomena in long-lived quasi-steady states of isolated quantum many-body systems driven at low frequencies. We obtain an analytical bound for the lifetime of the quasi-steady states which is exponentially large in the inverse driving frequency. Within this lifetime, the quasi-steady state is characterized by maximum entropy subject to the constraint of fixed number of particles in the systems Floquet-Bloch bands. In such a state, all the non-universal properties of these bands are washed out, hence only the topological properties persist.



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