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Edge Critical Behaviour of the 2-Dimensional Tri-critical Ising Model

Ian Affleck
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Abstract

Using previous results from boundary conformal field theory and integrability, a phase diagram is derived for the 2 dimensional Ising model at its bulk tri-critical point as a function of boundary magnetic field and boundary spin-coupling constant. A boundary tri-critical point separates phases where the spins on the boundary are ordered or disordered. In the latter range of coupling constant, there is a non-zero critical field where the magnetization is singular. In the former range, as the temperature is lowered, the boundary undergoes a first order transition while the bulk simultaneously undergoes a second order transition.

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Ian Affleck. 2000-05-17. Edge Critical Behaviour of the 2-Dimensional Tri-critical Ising Model. https://doi.org/10.1088/0305-4470%2F33%2F37%2F301

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