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Critical behavior of O(2)xO(N) symmetric models

Pasquale Calabrese·Pietro Parruccini·Andrea Pelissetto·Ettore Vicari
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Abstract

We investigate the controversial issue of the existence of universality classes describing critical phenomena in three-dimensional statistical systems characterized by a matrix order parameter with symmetry O(2)xO(N) and symmetry-breaking pattern O(2)xO(N) -> O(2)xO(N-2). Physical realizations of these systems are, for example, frustrated spin models with noncollinear order. Starting from the field-theoretical Landau-Ginzburg-Wilson Hamiltonian, we consider the massless critical theory and the minimal-subtraction scheme without epsilon expansion. The three-dimensional analysis of the corresponding five-loop expansions shows the existence of a stable fixed point for N=2 and N=3, confirming recent field-theoretical results based on a six-loop expansion in the alternative zero-momentum renormalization scheme defined in the massive disordered phase. In addition, we report numerical Monte Carlo simulations of a class of three-dimensional O(2)xO(2)-symmetric lattice models. The results provide further support to the existence of the O(2)xO(2) universality class predicted by the field-theoretical analyses.

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Pasquale Calabrese, Pietro Parruccini, Andrea Pelissetto, Ettore Vicari. 2004-09-17. Critical behavior of O(2)xO(N) symmetric models. https://doi.org/10.1103/physrevb.70.174439

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