1995/09/07 by P. Azaria, P. Lecheminant, D. mouhanna · 1 citation
Physics and Astronomy · #cond-mat #hep-th
paper · pdf · doi:10.1016/0550-3213(95)00514-s
published as Nucl.Phys. B455 (1995) 648-684 · 55 pages, Latex
arxiv created 1995/09/07 · arxiv updated 2009/11/30
We study the classical SU(N)⊗ U(1)/SU(N-1)⊗ U(1) Non Linear Sigma model which is the continuous low energy effective field theory for N component frustrated spin systems. The β functions for the two coupling constants of this model are calculated around two dimensions at two loop order in a low temperature expansion. Our study is completed by a large N analysis of the model. The β functions for the coupling constants and the mass gap are calculated in all dimensions between 2 and 4 at order 1/N. As a main result we show that the standard procedure at the basis of the 1/N expansion leads to results that partially contradict those of the weak coupling analysis. We finally present the procedure that reconciles the weak coupling and large N analysis, giving a consistent picture of the expected scaling of frustrated magnets.