Nanometric modulations of the magnetic structure of the element Nd

TL;DR

This study uses small-angle neutron scattering to uncover complex, nanometer-scale magnetic modulations in neodymium, revealing new phase-dependent vectors and spin textures likely stabilized by RKKY interactions.

Contribution

It reports previously unobserved modulation vectors and phase-dependent magnetic structures in Nd, advancing understanding of its complex magnetic ordering.

Findings

Identification of new modulation vectors in Nd

Detection of phase-dependent changes in magnetic order

Evidence of nanometer-scale spin textures stabilized by RKKY interactions

Abstract

The rare earth neodymium arguably exhibits the most complex magnetic ordering and series of magnetic phase transitions of the elements. Here we report the results of small-angle neutron scattering (SANS) measurements as a function of temperature and applied magnetic field to study magnetic correlations on nanometer length scales in Nd. The SANS measurements reveal the presence of previously unreported modulation vectors characterizing the ordered spin configuration which exhibit changes in magnitude and direction that are phase dependent. Between 5.9 and 7.6 K the additional modulation vector has a magnitude $Q$ =0.12 \AA$^{-1}$ and is primarily due to order of the Nd layers which contain a center of inversion. In this region of the phase diagram, the SANS measurements also identify a phase boundary at $\approx$1 T. An important feature of these modulation vectors is that they indicate the presence of nanometer length scale spin textures which are likely stabilized by frustrated Ruderman-Kittel-Kasuya-Yosida (RKKY) interactions rather than a Dzyaloshinskii-Moriya (DM) exchange interaction.