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arXiv:cond-mat/9707238 · Europhysics Letters (EPL)

Critical behavior of coupled q -state Potts models under weak disorder

Pascal Simon

Published Mar 15, 1998• 4 citations
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Abstract

We investigate the effects of weak disorder on different coupled q -state Potts models with q ⩽ 4 using two-loop renormalisation group equations. This study presents new examples of first-order transitions driven by randomness. We found that weak disorder makes the models decouple. Therefore, it appears that no relation emerges, at a perturbation level, between the disordered ( q 1 × q 2 )-state Potts model and the two disordered q 1 , q 2 -state Potts models ( q 1 ≠ q 2 ), though recent numerical investigations have shown that their central charges are approximately similar.

DOI
10.1209/epl/i1998-00200-6

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