The simplest approximation of integral coefficients in the equations of correlational magnetodynamics for ferromagnets

Abstract

The equations of correlational magnetodynamics (CMD) describe a magnet in the continuum approximation. The main problem in constructing CMD is the calculation of integral coefficients, in particular, the coefficient describing the production of short-range order, depending on the three-particle distribution functions and the structure of the crystal lattice. The work provides the simplest approximations for the integral coefficients of CMD based on the value of pair correlations at the phase transition point. To ensure an equilibrium solution, the coefficients are additionally determined in the upper part of the phase plane according to the assumption of a helical magnetization structure. The resulting approximation provides qualitative agreement with the simulation results within the framework of the original atomistic model of the magnet, and at the same time it turns out to be simple enough for further analysis.