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  • Letter
  • Open Access

Spin density waves and ground state helices in EuGa2.4Al1.6

M. T. Littlehales1,2,*, S. H. Moody3, P. J. Bereciartua4, D. A. Mayoh5, Z. B. Parkin1, T. J. Blundell6, E. Unsworth6, S. Francoual4, G. Balakrishnan5 et al.

D. Alba Venero2 and P. D. Hatton1,†

  • *Contact author: matthew.t.littlehales@durham.ac.uk
  • †Contact author: p.d.hatton@durham.ac.uk
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Phys. Rev. Research 6, L032015 – Published 19 July, 2024

DOI: https://doi.org/10.1103/PhysRevResearch.6.L032015

Abstract

The Eu(Ga1−xAlx)4 series is composed of centrosymmetric structures which exhibit a wide range of rich topological phenomena, including some members hosting magnetic skyrmions. In this letter, we investigate the previously unreported intermediate compound EuGa2.4Al1.6, which hosts two distinct phase transitions under zero applied magnetic field. We have used resonant elastic x-ray scattering with full linear polarization analysis to unambiguously determine the zero-field magnetic structures, which consist of a transition between a basal plane transverse spin density wave at higher temperatures into a noncollinear helical ground state. Furthermore, we demonstrate a phase coexistence regime below the transition and reveal an elliptically modulated helical magnetic structure emerging from wavevector splitting.

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Phys. Rev. Research 6, L032015– Published 19 July, 2024
  • Received 30 April 2024
  • Accepted 18 June 2024
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