Polarized neutron scattering study on the centrosymmetric skyrmion host material Gd2PdSi3

TL;DR

This study uses polarized neutron scattering to analyze the magnetic structures of the centrosymmetric skyrmion host Gd2PdSi3, revealing temperature-dependent magnetic phases and equal left- and right-handed spin helicities consistent with its crystal symmetry.

Contribution

First polarized neutron scattering investigation of Gd2PdSi3 confirming its elliptic screw magnetic structure and spin-helicity balance in the centrosymmetric skyrmion host.

Findings

Magnetic structure is elliptic screw-type with incommensurate q-vector.

Temperature increase induces sinusoidal magnetic modulations.

Equal fractions of left- and right-handed spin helicities are observed.

Abstract

We have investigated magnetic structures of the centrosymmetrric skyrmion material Gd2PdSi3 by means of polarized neutron scattering near zero field with an isotope-160Gd-enriched single crystal. In a previous study, magnetic structures in Gd2PdSi3 at low temperatures were studied by resonant X-ray scattering measurements [T. Kurumaji et al. Science 365, 914 (2019)]. The present polarized neutron results confirm that the magnetic structure in zero field has elliptic screw-type magnetic modulation with a propagation vector of (q, 0, 0) with q ~ 0.14 and its equivalents. As the temperature increases, the system undergoes a magnetic phase transition while keeping the incommensurate q-vector of (q,0,0). We found that the thermally-induced phase has sinusoidal magnetic modulations with magnetic moments perpendicular both to the c axis and to the q-vector. We also investigate the spin-helicity degree of freedom in the ground state by polarized neutrons, revealing that the system contains equal fractions of the left-handed and right-handed screw-type orders as expected from the centrosymmetric crystal structure.