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Gapping neutral modes in engineered quantum Hall edges

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 نشر من قبل Jukka V\\\"ayrynen
 تاريخ النشر 2021
  مجال البحث فيزياء
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Interferometry provides direct evidence for anyon statistics. In the fractional quantum Hall effect, interferometers are susceptible to dephasing by neutral modes. The latter support chargeless quasiparticles (neutralons) which propagate upstream along the edge and obey fractional statistics. Here we show that on a suitably engineered bilayer fractional quantum Hall edge, which is an experimentally available platform, the neutral modes can be gapped while leaving the desired charge modes gapless. The gapping mechanism is akin to a four-particle pairing superconductivity. Our considered bilayer structure can be shaped as an anyonic interferometer. We also discuss experimental charge transport signatures of the neutral mode gap.



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