Renormalisation Group Theory of Branching Potts Interfaces

John Cardy

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arXiv · cond-mat/9806098

Renormalisation Group Theory of Branching Potts Interfaces

John Cardy

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Abstract

We develop a field-theoretic representation for the configurations of an interface between two ordered phases of a q-state Potts model in two dimensions, in the solid-on-solid approximation. The model resembles the field theory of directed percolation and may be analysed using similar renormalisation group methods. In the one-loop approximation these reveal a simple mechanism for the emergence of a critical value q_c, such that for q q_c the interfacial width diverges at a finite value of the tension, indicating a first-order transition. The value of the Widom exponent for q minus infinity limit of our model corresponds to directed percolation and that the values for the exponents in the one-loop approximation are in reasonable agreement with accepted values.

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John Cardy. 1999-07-15. Renormalisation Group Theory of Branching Potts Interfaces. https://arxiv.org/abs/cond-mat/9806098

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