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On the self-consistent spin-wave theory of layered Heisenberg magnets

V. Yu. Irkhin·A. A. Katanin·M. I. Katsnelson
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Abstract

The versions of the self-consistent spin-wave theories (SSWT) of two-dimensional (2D) Heisenberg ferro- and antiferromagnets with a weak interlayer coupling and/or magnetic anisotropy, that are based on the non-linear Dyson-Maleev, Schwinger, and combined boson-pseudofermion representations, are analyzed. Analytical results for the temperature dependences of (sublattice) magnetization and short-range order parameter, and the critical points are obtained. The influence of external magnetic field is considered. Fluctuation corrections to SSWT are calculated within a random-phase approximation which takes into account correctly leading and next-leading logarithmic singularities. These corrections are demonstrated to improve radically the agreement with experimental data on layered perovskites and other systems. Thus an account of these fluctuations provides a quantitative theory of layered magnets.

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V. Yu. Irkhin, A. A. Katanin, M. I. Katsnelson. 1999-01-15. On the self-consistent spin-wave theory of layered Heisenberg magnets. https://doi.org/10.1103/physrevb.60.1082

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