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arXiv · 1110.3632

Breakdown of a perturbed Z_N topological phase

M. D. Schulz·S. Dusuel·R. Orus·J. Vidal·K. P. Schmidt
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Abstract

We study the robustness of a generalized Kitaev's toric code with Z_N degrees of freedom in the presence of local perturbations. For N=2, this model reduces to the conventional toric code in a uniform magnetic field. A quantitative analysis is performed for the perturbed Z_3 toric code by applying a combination of high-order series expansions and variational techniques. We provide strong evidences for first- and second-order phase transitions between topologically-ordered and polarized phases. Most interestingly, our results also indicate the existence of topological multi-critical points in the phase diagram.

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M. D. Schulz, S. Dusuel, R. Orus, J. Vidal, K. P. Schmidt. 2011-10-17. Breakdown of a perturbed Z_N topological phase. https://doi.org/10.1088/1367-2630/14/2/025005

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