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arXiv · 0902.0219

Topological quantum phase transition in an extended Kitaev spin model

Xiao-Feng Shi·Yue Yu·J. Q. You·Franco Nori
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Abstract

We study the quantum phase transition between Abelian and non-Abelian phases in an extended Kitaev spin model on the honeycomb lattice, where the periodic boundary condition is applied by placing the lattice on a torus. Our analytical results show that this spin model exhibits a continuous quantum phase transition. Also, we reveal the relationship between bipartite entanglement and the ground-state energy. Our approach directly shows that both the entanglement and the ground-state energy can be used to characterize the topological quantum phase transition in the extended Kitaev spin model.

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Xiao-Feng Shi, Yue Yu, J. Q. You, Franco Nori. 2009-02-08. Topological quantum phase transition in an extended Kitaev spin model. https://doi.org/10.1103/physrevb.79.134431

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