Signatures of Majorana Fermions in Topological Insulator Josephson Junction Devices

摘要

We study theoretically the electrical current and low-frequency noise for alinear Josephson junction structure on a topological insulator, in which thesuperconductor forms a closed ring and currents are injected from normalregions inside and outside the ring. We find that this geometry offers asignature for the presence of gapless 1D Majorana fermion modes that arepredicted in the channel when the phase difference \phi, controlled by themagnetic flux through the ring, is \pi. We show that for low temperature thelinear conductance jumps when \phi\ passes through \pi, accompanied bynon-local correlations between the currents from the inside and outside of thering. We compute the dependence of these features on temperature, voltage andlinear dimensions, and discuss the implications for experiments.