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Topological Order Following a Quantum Quench

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 نشر من قبل Dimitris Tsomokos Dr
 تاريخ النشر 2009
  مجال البحث فيزياء
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We determine the conditions under which topological order survives a rapid quantum quench. Specifically, we consider the case where a quantum spin system is prepared in the ground state of the Toric Code Model and, after the quench, it evolves with a Hamiltonian that does not support topological order. We provide analytical results supported by numerical evidence for a variety of quench Hamiltonians. The robustness of topological order under non-equilibrium situations is tested by studying the topological entropy and a novel dynamical measure, which makes use of the similarity between partial density matrices obtained from different topological sectors.



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