Small-angle neutron scattering in the fully polarized phase of noncollinear magnets with interfacial-like Dzyaloshinskii-Moriya interaction

Physical Review B: Condensed Matter and Materials Physics. 2022. Vol. 106. No. 17. Article 174408.

Utesov O.

Spin waves in noncollinear magnets with Cnv symmetry are discussed in the context of inelastic neutron
scattering in small-angle scattering geometry. In the framework of aminimal model including exchange coupling,
Dzyaloshinskii-Moriya interaction (DMI), and single-ion anisotropy, we consider the system properties at
moderate external magnetic fields and in the high-field fully polarized phase. In the latter case, the magnon
spectrum is gapped and nonreciprocal due to DMI with the minimum perpendicular to the field direction for the
in-plane field and is ferromagneticlike for the field along the high-symmetry axis. Inelastic spin-wave small-angle
neutron scattering (SWSANS) in the fully polarized phase is considered in four different geometries. It is shown
that analysis of the field dependence of the SWSANS cutoff feature in these geometries allows determining
all important parameters of the model. The possibility of the proposed method utilization in thin films with
interfacial DMI is also discussed.

Keywords: тонкие пленки, thin films, magnons, магноны, Взаимодействие Дзялошинского-Мория, Dzyaloshinskii-Moriya interaction, small-angle neutron scattering, малоугловое рассеяние нейтронов