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Helical superconducting edge modes from pseudo-Landau levels in graphene

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 نشر من قبل Daniel Sabsovich
 تاريخ النشر 2020
  مجال البحث فيزياء
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We explore Andreev states at the interface of graphene and a superconductor for a uniform pseudo-magnetic field. Near the zeroth-pseudo Landau level, we find a topological transition as a function of applied Zeeman field, at which a gapless helical mode appears. This 1D mode is protected from backscattering as long as intervalley- and spin-flip scattering are suppressed. We discuss a possible experimental platform to detect this gapless mode based on strained suspended membranes on a superconductor, in which dynamical strain causes charge pumping



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