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arXiv · 1301.5822

Fractional Fermions with Non-Abelian Statistics

Jelena Klinovaja·Daniel Loss
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Abstract

We introduce a novel class of low-dimensional topological tight-binding models that allow for bound states that are fractionally charged fermions and exhibit non-Abelian braiding statistics. The proposed model consists of a double (single) ladder of spinless (spinful) fermions in the presence of magnetic fields. We study the system analytically in the continuum limit as well as numerically in the tight-binding representation. We find a topological phase transition with a topological gap that closes and reopens as a function of system parameters and chemical potential. The topological phase is of the type BDI and carries two degenerate mid-gap bound states that are localized at opposite ends of the ladders. We show numerically that these bound states are robust against a wide class of perturbations.

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Jelena Klinovaja, Daniel Loss. 2013-01-24. Fractional Fermions with Non-Abelian Statistics. https://doi.org/10.1103/physrevlett.110.126402

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