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arXiv · 1511.02817

Topological order in the Kitaev/Majorana chain in the presence of disorder and interactions

Niklas M. Gergs·Lars Fritz·Dirk Schuricht
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Abstract

We study the combined effect of interactions and disorder on topological order in one dimension. To this end we consider a generalized Kitaev chain including fermion-fermion interactions and disorder in the chemical potential. We determine the phase diagram by performing density-matrix renormalization group calculations on the corresponding spin-1/2 chain. We find that moderate disorder or repulsive interactions individually stabilize the topological order, which remains valid for their combined effect. However, both repulsive and attractive interactions lead to a suppression of the topological phase at strong disorder.

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Niklas M. Gergs, Lars Fritz, Dirk Schuricht. 2017-05-01. Topological order in the Kitaev/Majorana chain in the presence of disorder and interactions. https://doi.org/10.1103/physrevb.93.075129

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