Title: Emergent universal critical behavior of the 2D N-color Ashkin-Teller model in the presence of correlated disorder
Author(s):

	M. Dudka (Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine, 79011 Lviv, Ukraine) ,
	A.A. Fedorenko (Laboratoire de Physique, ENS de Lyon, Univ Claude Bernard, Univ Lyon, CNRS, F-69342 Lyon, France)

We study the critical behavior of the 2D N-color Ashkin-Teller model in the presence of random bond disorder whose correlations decays with the distance r as a power-law r^-a. We consider the case when the spins of different colors sitting at the same site are coupled by the same bond and map this problem onto the 2D system of N/2 flavors of interacting Dirac fermions in the presence of correlated disorder. Using renormalization group we show that for N=2, a "weakly universal" scaling behavior at the continuous transition becomes universal with new critical exponents. For N>2, the first-order phase transition is rounded by the correlated disorder and turns into a continuous one.

Key words: phase transitions, correlated disorder, two-dimensional models, Dirac fermions, renormalization group
PACS: 61.43.-j, 64.60.ae, 64.60.Bd, 75.10.Hk

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