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Liebs Theorem and Maximum Entropy Condensates

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 نشر من قبل Joseph Tindall
 تاريخ النشر 2021
  مجال البحث فيزياء
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Coherent driving has established itself as a powerful tool for guiding a many-body quantum system into a desirable, correlated pre-thermal regime. The focus on this transient regime where heating is slow is a result of the intuition that a thermodynamically large system will inevitably saturate to a featureless infinite temperature state under continuous driving. Here we show that whether or not Floquet heating is a deleterious effect actually depends on the geometry of the system. Specifically, we prove that the maximum entropy steady states which form upon driving the ground state of the Hubbard model on unbalanced bi-partite lattices possess uniform off-diagonal long-range order which remains finite even in the thermodynamic limit. This creation of a `hot condensate can occur on any driven unbalanced lattice and provides an understanding of how heating can expose order which has been suppressed by the lattice geometry. We discuss implications for recent experiments observing emergent superconductivity in photoexcited materials.



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