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arXiv · 2108.05360

Topologically enabled superconductivity

Michael A. Rampp·Elio J. König·Jörg Schmalian
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Abstract

Majorana zero modes are a much sought-after consequence of one-dimensional topological superconductivity. Here, we show that, in turn, zero modes accompanying dynamical instanton events strongly enhance -- in some cases even enable -- superconductivity. We find that the dynamics of a one-dimensional topological triplet superconductor is governed by a $\theta$ term in the action. For isotropic triplets, this term enables algebraic charge-$2e$ superconductivity, which is destroyed by fluctuations in nontopological superconductors. For anisotropic triplets, zero modes suppress quantum phase slips and stabilize superconductivity over a large region of the phase diagram. We present predictions of correlation functions and thermodynamics for states of topologically enhanced superconductivity.

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Michael A. Rampp, Elio J. König, Jörg Schmalian. 2021-08-11. Topologically enabled superconductivity. https://doi.org/10.1103/physrevlett.129.077001

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