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arXiv · 1612.07410

Fractional spin and Josephson effect in time-reversal-invariant topological superconductors

Alberto Camjayi·Liliana Arrachea·Armando Aligia·Felix von Oppen
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Abstract

Time reversal invariant topological superconducting (TRITOPS) wires are known to host a fractional spin hbar/4 at their ends. We investigate how this fractional spin affects the Josephson current in a TRITOPS-quantum dot-TRITOPS Josephson junction, describing the wire in a model which can be tuned between a topological and a nontopological phase. We compute the equilibrium Josephson current of the full model by continuous-time Monte Carlo simulations and interpret the results within an effective low-energy theory. We show that in the topological phase, the 0-to-pi transition is quenched via formation of a spin singlet from the quantum dot spin and the fractional spins associated with the two adjacent topological superconductors.

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Alberto Camjayi, Liliana Arrachea, Armando Aligia, Felix von Oppen. 2017-07-31. Fractional spin and Josephson effect in time-reversal-invariant topological superconductors. https://doi.org/10.1103/physrevlett.119.046801

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