Anomalous dimensions of composite operators near two dimensions for ferromagnets withO(n)symmetry

Abstract

Relevant symmetry-breaking operators for $n$-vector models ($n>\mathrm{}2\mathrm{}$) are considered near two dimensions. There is an infinite set of relevant operators; all the eigenoperators are determined and their anomalous dimension calculated to second order in $d-2\mathrm{}$. Isotropic corrections to scaling are also considered. They correspond to symmetric irrelevant operators. Five of them dominate near two dimensions; the leading one gives the correction-to-scaling exponent $\omega$, calculated here at first order in $d-2\mathrm{}$.