Singularities in ground state fidelity and quantum phase transitions for the Kitaev model

Jian-Hui Zhao; Huan-Qiang Zhou

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arXiv · 0803.0814

Singularities in ground state fidelity and quantum phase transitions for the Kitaev model

Jian-Hui Zhao·Huan-Qiang Zhou

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Abstract

The ground state fidelity per lattice site is shown to be able to detect quantum phase transitions for the Kitaev model on the honeycomb lattice, a prototypical example of quantum lattice systems with topological order. It is found that, in the thermodynamic limit, the ground state fidelity per lattice site is non-analytic at the phase boundaries: the second-order derivative of its logarithmic function with respect to a control parameter describing the interaction between neighboring spins is logarithmically divergent. A finite size scaling analysis is performed, which allows us to extract the correlation length critical exponent from the scaling behaviors of the ground state fidelity per lattice site.

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Jian-Hui Zhao, Huan-Qiang Zhou. 2008-03-06. Singularities in ground state fidelity and quantum phase transitions for the Kitaev model. https://arxiv.org/abs/0803.0814

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