Non-Abelian parafermions in time-reversal-invariant interacting helical systems
Publikation: Beitrag in Fachzeitschrift › Forschungsartikel › Beigetragen › Begutachtung
Beitragende
Abstract
The interplay between bulk spin-orbit coupling and electron-electron interactions produces umklapp scattering in the helical edge states of a two-dimensional topological insulator. If the chemical potential is at the Dirac point, umklapp scattering can open a gap in the edge state spectrum even if the system is time-reversal invariant. We determine the zero-energy bound states at the interfaces between a section of a helical liquid which is gapped out by the superconducting proximity effect and a section gapped out by umklapp scattering. We show that these interfaces pin charges which are multiples of e/2, giving rise to a Josephson current with 8π periodicity. Moreover, the bound states, which are protected by time-reversal symmetry, are fourfold degenerate and can be described as Z4 parafermions. We determine their braiding statistics and show how braiding can be implemented in topological insulator systems.
Details
Originalsprache | Englisch |
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Aufsatznummer | 081406 |
Fachzeitschrift | Physical Review B - Condensed Matter and Materials Physics |
Jahrgang | 91 |
Ausgabenummer | 8 |
Publikationsstatus | Veröffentlicht - 25 Feb. 2015 |
Peer-Review-Status | Ja |