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Deconfinement of Majorana vortex modes produces a superconducting Landau level

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 نشر من قبل Micha{\\l} Jan Pacholski
 تاريخ النشر 2021
  مجال البحث فيزياء
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A spatially oscillating pair potential $Delta(r)=Delta_0 e^{2i Kcdot r}$ with momentum $K>Delta_0/hbar v$ drives a deconfinement transition of the Majorana bound states in the vortex cores of a Fu-Kane heterostructure (a 3D topological insulator with Fermi velocity $v$, on a superconducting substrate with gap $Delta_0$, in a perpendicular magnetic field). In the deconfined phase at zero chemical potential the Majorana fermions form a dispersionless Landau level, protected by chiral symmetry against broadening due to vortex scattering. The coherent superposition of electrons and holes in the Majorana Landau level is detectable as a local density of states oscillation with wave vector $sqrt{K^2-(Delta_0/hbar v)^2}$. The striped pattern also provides a means to measure the chirality of the Majorana fermions.



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