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arXiv · 1312.5723

Unconventional topological phase transitions in helical Shiba chains

Falko Pientka·Leonid I. Glazman·Felix von Oppen
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Abstract

Chains of magnetic impurities placed on a superconducting substrate and forming helical spin order provide a promising venue for realizing a topological superconducting phase. An effective tight-binding description of such helical Shiba chains involves long-range (power-law) hopping and pairing amplitudes which induce an unconventional topological critical point. At the critical point, we find exponentially localized Majorana bound states with a short localization length unrelated to a topological gap. Away from the critical point, this exponential decay develops a power-law tail. Our analytical results have encouraging implications for experiment.

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Falko Pientka, Leonid I. Glazman, Felix von Oppen. 2014-06-11. Unconventional topological phase transitions in helical Shiba chains. https://doi.org/10.1103/physrevb.89.180505

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