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arXiv · hep-lat/9508033

Critical Behaviour of the Two Dimensional Step Model

A. C. Irving·R. Kenna
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Abstract

We use finite--size scaling of Lee--Yang partition function zeroes to study the critical behaviour of the two dimensional step or sgn $O(2)$ model. We present evidence that, like the closely related $XY$--model, this has a phase transition from a disordered high temperature phase to a low temperature massless phase where the model remains critical. The critical parameters (including logarithmic corrections) are compatible with those of the $XY$--model indicating that both models belong to the same universality class.

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A. C. Irving, R. Kenna. 1996-02-01. Critical Behaviour of the Two Dimensional Step Model. https://doi.org/10.1103/physrevb.53.11568

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