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Quantum noise detects Floquet topological phases

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 نشر من قبل Babak Seradjeh
 تاريخ النشر 2018
  مجال البحث فيزياء
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We study quantum noise in a nonequilibrium, periodically driven, open system attached to static leads. Using a Floquet Greens function formalism we show, both analytically and numerically, that local voltage noise spectra can detect the rich structure of Floquet topological phases unambiguously. Remarkably, both regular and anomalous Floquet topological bound states can be detected, and distinguished, via peak structures of noise spectra at the edge around zero-, half-, and full-drive-frequency. We also show that the topological features of local noise are robust against moderate disorder. Thus, local noise measurements are sensitive detectors of Floquet topological phases.



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