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arXiv · 1702.02525

Measuring Majorana non-locality and spin structure with a quantum dot

Elsa Prada·Ramón Aguado·Pablo San-Jose
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Abstract

Robust zero bias transport anomalies in semiconducting nanowires with proximity-induced superconductivity have been convincingly demonstrated in various experiments. While these are compatible with the existence of Majorana zero modes at the ends of the nanowire, a direct proof of their non-locality and topological protection is now needed. Here we show that a quantum dot at the end of the nanowire may be used as a powerful spectroscopic tool to quantify the degree of Majorana non-locality through a local transport measurement. Moreover, the spin polarization of dot sub-gap states at singlet-doublet transitions in the Coulomb blockade regime allows the dot to directly probe the spin structure of the Majorana wave function, and indirectly measure the spin-orbit coupling of the nanowire.

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Elsa Prada, Ramón Aguado, Pablo San-Jose. 2017-08-13. Measuring Majorana non-locality and spin structure with a quantum dot. https://doi.org/10.1103/physrevb.96.085418

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