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arXiv · 1105.5835

Zero energy Majorana modes in spin ladders and a possible realization of the Kitaev model

A. A. Nersesyan·A. M. Tsvelik
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Abstract

We show that in double-chain Mott insulators (ladders), disordered alternating ionic potentials may locally destroy coherence of magnetic excitations and lead to the appearance of spontaneously dimerized islands inside the Haldane spin-liquid phase. We argue that a boundary between the dimerized and Haldane phases of a spin-1/2 ladder supports a localized zero-energy Majorana fermion mode. Based on these findings we suggest a realization of a generalized Kitaev model where Majorana fermions can propagate in more than one dimension.

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A. A. Nersesyan, A. M. Tsvelik. 2011-08-04. Zero energy Majorana modes in spin ladders and a possible realization of the Kitaev model. https://doi.org/10.1209/0295-5075%2F96%2F17002

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