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arXiv · 1201.6409

Phase diagram of the toric code model in a parallel magnetic field

Fengcheng Wu·Youjin Deng·Nikolay Prokof'ev
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Abstract

Ground-state phase diagram of the toric code model in a parallel magnetic field has three distinct phases: topological, charge-condensed, and vortex-condensed states. To study it we consider an implicit local order parameter characterizing the transition between the topological and charge-condensed phases, and sample it using continuous-time Monte Carlo simulations. The corresponding second-order transition line is obtained by finite-size scaling analysis of this order parameter. Symmetry breaking between charges and vortices along the first-order transition line is also observed, and our numerical result shows that the end point of the first-order transition line is located at $h_x^{(c)}=h_z^{(c)}=0.418(2)$.

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Fengcheng Wu, Youjin Deng, Nikolay Prokof'ev. 2012-01-31. Phase diagram of the toric code model in a parallel magnetic field. https://doi.org/10.1103/physrevb.85.195104

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