Fractional Spin and Josephson Effect in Time-Reversal-Invariant Topological Superconductors

Time-reversal-invariant topological superconducting (TRITOPS) wires are known to host a fractional spin /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 that can be tuned betwee...

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Detalles Bibliográficos
Autores principales: Camjayi, A., Arrachea, L., Aligia, A., Von Oppen, F.
Formato: JOUR
Materias:
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_00319007_v119_n4_p_Camjayi
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Descripción
Sumario:Time-reversal-invariant topological superconducting (TRITOPS) wires are known to host a fractional spin /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 that 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-π 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. © 2017 American Physical Society.