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Large-n Critical Behavior of O(n)xO(m) Spin Models

Andrea Pelissetto·Paolo Rossi·Ettore Vicari
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Abstract

We consider the Landau-Ginzburg-Wilson Hamiltonian with O(n)x O(m) symmetry and compute the critical exponents at all fixed points to O(n^{-2}) and to O(ε^3) in a ε=4-d expansion. We also consider the corresponding non-linear sigma model and determine the fixed points and the critical exponents to O(\tildeε^2) in the \tildeε=d-2 expansion. Using these results, we draw quite general conclusions on the fixed-point structure of models with O(n)xO(m) symmetry for n large and all 2 < d < 4.

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Andrea Pelissetto, Paolo Rossi, Ettore Vicari. 2001-05-08. Large-n Critical Behavior of O(n)xO(m) Spin Models. https://doi.org/10.1016/s0550-3213(01)00223-1

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