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Exact solution of the anisotropic special transition in the O(n) model in 2D

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 نشر من قبل Jerome Dubail
 تاريخ النشر 2009
  مجال البحث فيزياء
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 تأليف Jerome Dubail




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The effect of surface exchange anisotropies is known to play a important role in magnetic critical and multicritical behavior at surfaces. We give an exact analysis of this problem in d=2 for the O(n) model by using Coulomb gas, conformal invariance and integrability techniques. We obtain the full set of critical exponents at the anisotropic special transition--where the symmetry on the boundary is broken down to O(n_1)xO(n-n_1)--as a function of n_1. We also obtain the full phase diagram and crossover exponents. Crucial in this analysis is a new solution of the boundary Yang-Baxter equations for loop models. The appearance of the generalization of Schramm-Loewner Evolution SLE_{kappa,rho} is also discussed.

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