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arXiv · 1408.3804

Detecting a quantum critical point in topological SN junctions

Yashar Komijani·Ian Affleck
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Abstract

A spin-orbit coupled quantum wire, with one end proximate to an s-wave superconductor, can become a topological superconductor, with a Majorana mode localized at each end of the superconducting region. It was recently shown that coupling one end of such a topological superconductor to $two$ normal channels of interacting electrons leads to a novel type of frustration and a quantum critical point when both channels couple with equal strength. We propose an experimental method to access this critical point in a $single$ quantum wire and show its resilience to disorder.

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Yashar Komijani, Ian Affleck. 2014-08-17. Detecting a quantum critical point in topological SN junctions. https://doi.org/10.1103/physrevb.90.115107

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