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arXiv · 0803.1292

Fidelity susceptibility and long-range correlation in the Kitaev honeycomb model

Shuo Yang·Shi-Jian Gu·Chang-Pu Sun·Hai-Qing Lin
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Abstract

We study exactly both the ground-state fidelity susceptibility and bond-bond correlation function in the Kitaev honeycomb model. Our results show that the fidelity susceptibility can be used to identify the topological phase transition from a gapped A phase with Abelian anyon excitations to a gapless B phase with non-Abelian anyon excitations. We also find that the bond-bond correlation function decays exponentially in the gapped phase, but algebraically in the gapless phase. For the former case, the correlation length is found to be $1/ξ=2\sinh^{-1}[\sqrt{2J_z -1}/(1-J_z)]$, which diverges around the critical point $J_z=(1/2)^+$.

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Shuo Yang, Shi-Jian Gu, Chang-Pu Sun, Hai-Qing Lin. 2008-07-03. Fidelity susceptibility and long-range correlation in the Kitaev honeycomb model. https://doi.org/10.1103/physreva.78.012304

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