# Critical points of coupled vector-Ising systems. Exact results

@article{Delfino2019CriticalPO, title={Critical points of coupled vector-Ising systems. Exact results}, author={Gesualdo Delfino and Noel Lamsen}, journal={Journal of Physics A: Mathematical and Theoretical}, year={2019} }

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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