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Vortex Dynamics, Pinning, and Magic Angles on Moire Patterns

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 نشر من قبل Cynthia J. Olson Reichhardt
 تاريخ النشر 2020
  مجال البحث فيزياء
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We examine pinning and dynamics of Abrikosov vortices interacting with pinning centers placed in a moire pattern for varied moire lattice angles. We find a series of magic angles at which the critical current shows a pronounced dip corresponding to lattices in which the vortices can flow along quasi-one-dimensional channels. At these magic angles, the vortices move with a finite Hall angle. Additionally, for some lattice angles there are peaks in the critical current produced when the substrate has a quasiperiodic character that strongly reduces the vortex channeling. Our results should be general to a broad class of particle-like assemblies moving on moire patterns.



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