Thermodynamically stable equal-module exchange magnetic classes

TL;DR

This paper demonstrates that within Landau theory, equilibrium equal-module exchange magnetic structures naturally emerge as stable states in magnetic crystals without extra conditions or dimensional constraints.

Contribution

It introduces a general scheme showing the automatic appearance of stable equal-module exchange structures in magnetic crystals, bypassing previous limitations.

Findings

Equal-module exchange structures are thermodynamically stable.

No additional conditions like the Andreev-Marchenko scalar are required.

Structures are not limited by the irreducible representation dimensionality.

Abstract

It is shown that within the framework of application of the general scheme of the Landau theory of phase transitions to the magnetic crystals the equilibrium and stable equal-module exchange structures automatically appears in addition to the other magnetic states. No additional conditions such as the existence of the Andreev-Marchenko spin scalar are needed. Furthermore, they are not constrained by the dimensionality of irreducible representation as it typically takes place for the Andreev-Marchenko-type structures.