Relative effectiveness of biquadratic interactions and stabilizing DMI

Determine whether, for the coplanar four-sublattice ground state on the rotated square lattice considered in the paper, the biquadratic interaction is the most effective term for generating magnon magnetic moment and whether a stabilizing Dzyaloshinskii–Moriya interaction decreases the magnitude of that magnetic moment.

Background

The paper studies magnons in a coplanar odd-parity-wave magnetic ground state on a rotated square lattice with four sublattices. Because the magnon spin vanishes in this state, the magnetic moment is purely orbital. Numerical spectra for several parameter sets compare the effects of biquadratic interactions, easy-plane and easy-axis anisotropies, and out-of-plane Dzyaloshinskii–Moriya interaction (DMI) on the magnitude of the magnon magnetic moment.

For the parameter set in which DMI is the principal mechanism stabilizing the ground state, with biquadratic interactions and easy-plane anisotropy removed, the calculated magnetic moment is significantly smaller than in the other cases. The authors therefore formulate an explicit conjecture concerning the comparative role of biquadratic interactions and stabilizing versus destabilizing DMI; the paper does not establish this conjecture analytically or across the full parameter space.

References

We conjecture that for this GS, the biquadratic term is most effective at generating magnon magnetic moment, while a stabilizing DMI leads to a decrease of the magnitude of the magnetic moment.

— Orbital current rectifier and linear magnon Edelstein effect in $p$-wave antialtermagnets  (2609.03075 - Mæland et al., 2 Sep 2026) in Section 3.2, subsection “Magnon magnetic moment,” discussion of Fig. 2(e)