SPIN-WAVE CORRECTIONS TO SINGLE-DOMAIN BEHAVIOR IN FINITE FERROMAGNETIC SYSTEMS

Near the phase boundary at (H equals 0, 0 less than T less than T//c) ferromagnetic n-vector spin systems of finite dimensions, L**d, with periodic boundary conditions act, in leading order, as uniformly magnetized domains. However, spin-wave fluctuations, present for n greater than equivalent to 2, interfere with single-domain behavior entering, technically, as dangerous corrections to scaling of relative order 1/L**d** minus **2. Detailed results on the scaling of rounded first-order transitions with superimposed spin-wave singularities are reported for short-range interactions and general n and d.