Large n critical behavior of O( n)× O( m) spin models
Abstract
We consider the LandauGinzburgWilson Hamiltonian with O( n)× O( m) symmetry and compute the critical exponents at all fixed points to O( n^{2}) and to O( ɛ^{3}) in a ɛ=4 d expansion. We also consider the corresponding nonlinear σmodel and determine the fixed points and the critical exponents to O( ɛ∼^{2}) in the ɛ∼=d2 expansion. Using these results, we draw quite general conclusions on the fixedpoint structure of models with O( n)× O( m) symmetry for n large and all 2⩽ d⩽4.
 Publication:

Nuclear Physics B
 Pub Date:
 July 2001
 DOI:
 10.1016/S05503213(01)002231
 arXiv:
 arXiv:hepth/0104024
 Bibcode:
 2001NuPhB.607..605P
 Keywords:

 High Energy Physics  Theory;
 Condensed Matter;
 High Energy Physics  Lattice
 EPrint:
 29 pages, a few refs added, Nucl. Phys. B in press