Critical points of coupled vector-Ising systems. Exact results

  title={Critical points of coupled vector-Ising systems. Exact results},
  author={Gesualdo Delfino and Noel Lamsen},
  journal={Journal of Physics A: Mathematical and Theoretical},
  • G. Delfino, Noel Lamsen
  • Published 26 February 2019
  • Physics
  • Journal of Physics A: Mathematical and Theoretical
We show that scale invariant scattering theory allows to exactly determine the critical points of two-dimensional systems with coupled $O(N)$ and Ising order pameters. The results are obtained for $N$ continuous and include criticality of loop gas type. In particular, for $N=1$ we exhibit three critical lines intersecting at the Berezinskii-Kosterlitz-Thouless transition point of the Gaussian model and related to the $Z_4$ symmetry of the isotropic Ashkin-Teller model. For $N=2$ we classify the… Expand
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