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arXiv · 1012.1740

Robustness of a perturbed topological phase

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

We investigate the stability of the topological phase of the toric code model in the presence of a uniform magnetic field by means of variational and high-order series expansion approaches. We find that when this perturbation is strong enough, the system undergoes a topological phase transition whose first- or second-order nature depends on the field orientation. When this transition is of second order, it is in the Ising universality class except for a special line on which the critical exponent driving the closure of the gap varies continuously, unveiling a new topological universality class.

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S. Dusuel, M. Kamfor, R. Orus, K. P. Schmidt, J. Vidal. 2010-12-08. Robustness of a perturbed topological phase. https://doi.org/10.1103/physrevlett.106.107203

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