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.
@article{arxiv.1612.07410,
title = {Fractional spin and Josephson effect in time-reversal-invariant topological superconductors},
author = {Alberto Camjayi and Liliana Arrachea and Armando Aligia and Felix von Oppen},
journal= {arXiv preprint arXiv:1612.07410},
year = {2017}
}
Comments
4+1 pages, 3 figures, supplemental material (published version)