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arXiv · 1609.04848

Ballistic edge states in Bismuth nanowires revealed by SQUID interferometry

Anil Murani·Alik Kasumov·Shamashis Sengupta·Yu. A. Kasumov·V. T. Volkov·I. I. Khodos·F. Brisset·Raphaëlle Delagrange·Alexei Chepelianskii·Richard Deblock·Hélène Bouchiat·Sophie Guéron
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Abstract

Spin-orbit interactions are known to have drastic effects on the band structure of heavy-element-based materials. Celebrated examples are the recently identified 3D and 2D topological insulators. In those systems transport takes place at surfaces or along edges, and spin-momentum locking provides protection against (non-magnetic) impurity scattering, favoring spin-polarized ballistic transport. We have used the measurement of the current phase relation of a micrometer-long single crystal bismuth nanowire connected to superconducting electrodes, to demonstrate that transport occurs ballistically along two edges of this high-spin-orbit material. In addition, we show that a magnetic field can induce to 0-pi transitions and phi0-junction behavior, thanks to the extraordinarily high g-factor and spin orbit coupling in this system, providing a way to manipulate the phase of the supercurrent-carrying edge states.

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Anil Murani, Alik Kasumov, Shamashis Sengupta, Yu. A. Kasumov, V. T. Volkov, I. I. Khodos, F. Brisset, Raphaëlle Delagrange, Alexei Chepelianskii, Richard Deblock, Hélène Bouchiat, Sophie Guéron. 2016-09-15. Ballistic edge states in Bismuth nanowires revealed by SQUID interferometry. https://doi.org/10.1038/ncomms15941

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