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arXiv · 1108.3870

Non-equilibrium Josephson effect through helical edge states

Driss M. Badiane·Manuel Houzet·Julia S. Meyer
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Abstract

We study Josephson junctions between superconductors connected through the helical edge states of a two-dimensional topological insulator in the presence of a magnetic barrier. As the equilibrium Andreev bound states of the junction are 4Pi-periodic in the superconducting phase difference, it was speculated that, at finite dc bias voltage, the junction exhibits a fractional Josephson effect with half the Josephson frequency. Using the scattering matrix formalism, we show that signatures of this effect can be seen in the finite-frequency current noise. Furthermore, we discuss other manifestations of the Majorana bound states forming at the edges of the superconductors.

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Driss M. Badiane, Manuel Houzet, Julia S. Meyer. 2011-08-18. Non-equilibrium Josephson effect through helical edge states. https://doi.org/10.1103/physrevlett.107.177002

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