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arXiv · 1412.8183

Majorana Edge States and Braiding in an Exactly Solvable One-dimensional Spin Model

Zhao-Yang Dong·Jian-Xin Li
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Abstract

We derive an exactly solvable one-dimensional (1D) spin model from the three-band Hubbard model with a strong spin-orbit coupling by introducing U(1) gauge fields to the isospin states. We find that it has a topological nontrivial phase characterized by Majorana end modes which are protected by a new Z_2 topological invariant related to the parity of the lattice sites (odd or even number of sites) in the spin chain. With the protection of this Z_2 topological invariant, a novel braiding of two Majorana edge states in this strictly geometric 1D chain is realized. We also discuss the possible realization of the gauge fields.

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Zhao-Yang Dong, Jian-Xin Li. 2014-12-28. Majorana Edge States and Braiding in an Exactly Solvable One-dimensional Spin Model. https://arxiv.org/abs/1412.8183

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