DOI: https://doi.org/10.30970/jps.02.224
CRITICAL PHENOMENA IN 2D ANISOTROPIC SPIN SYSTEMS WITH WEAK DISORDER
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Journal of Physical Studies 2(2), 224–227 (1998)
DOI: https://doi.org/10.30970/jps.02.224 CRITICAL PHENOMENA IN 2D ANISOTROPIC SPIN SYSTEMS WITH WEAK DISORDER |
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G. Jug\dagger, B. N. Shalaev\dagger\dagger
\daggerINFM and Instituto di Scienze Matematiche, Fisiche e Chimiche
Università di Milano a Como, Via Lucini 3, 22100 Como (Italy)
\dagger\daggerA. F. Ioffe Physical \& Technical Institute,
Russian Academy of Sciences
194021 St.Petersburg (Russia)
The critical behavior of 2D anisotropic systems with weak quenched disorder described by the so–called generalized Ashkin–Teller model (GATM), including the Ising model with random bonds, the dilute Baxter model, the impure $N$–color Ashkin–Teller model, and minimal conformal field theory models (MCFTM) with $c<1$ ($c$ is the central charge) perturbed by randomness is discussed. All these models except MCFTM were found to belong to the Ising model universality class. Critical exponents of disordered MCFTM are calculated within perturbative expansions in the powers of $ϵ=c-1/2$. RG flows exhibit the rounding of fluctuation–driven first–order phase transitions by disorder.