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arXiv · 1202.2837

Interplay of disorder and interaction in Majorana quantum wires

Alejandro M. Lobos·Roman M. Lutchyn·S. Das Sarma
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Abstract

We study the interplay between disorder and interaction in one-dimensional topological superconductors which carry localized Majorana zero-energy states. Using Abelian bosonization and the perturbative renormalization group (RG) approach, we obtain the RG-flow and the associated scaling dimensions of the parameters and identify the critical points of the low-energy theory. We predict a quantum phase transition from a topological superconducting phase to a non-topological localized phase, and obtain the phase boundary between these two phases as a function of the electron-electron interaction and the disorder strength in the nanowire. Based on an instanton analysis which incorporates the effect of disorder, we also identify a large regime of stability of the Majorana-carrying topological phase in the parameter space of the model.

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Alejandro M. Lobos, Roman M. Lutchyn, S. Das Sarma. 2012-07-02. Interplay of disorder and interaction in Majorana quantum wires. https://doi.org/10.1103/physrevlett.109.146403

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