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Low-temperature skyrmions and spiral reorientation processes in chiral magnets with cubic anisotropy: Guidelines for bridging theory and experiment

A. O. Leonov1,2,*, G. Gödecke3,†, J. Grefe3, S. Süllow3, and D. Menzel3

  • 1Department of Chemistry, Faculty of Science, Hiroshima University Kagamiyama, Higashi Hiroshima, Hiroshima 739-8526, Japan
  • 2International Institute for Sustainability with Knotted Chiral Meta Matter (WPI-SKCM2), Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
  • 3Institut für Physik der Kondensierten Materie, TU Braunschweig, D-38106 Braunschweig, Germany

  • *Contact author: leonov@hiroshima-u.ac.jp
  • †Contact author: g.goedecke@tu-braunschweig.de
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Phys. Rev. Research 8, 013130 – Published 5 February, 2026

DOI: https://doi.org/10.1103/645q-nz7t

Abstract

We revisit the phenomenological Dzyaloshinskii framework, a central theoretical approach for describing magnetization processes in bulk chiral magnets, and demonstrate how magnetocrystalline cubic anisotropy reshapes the phase diagrams of states and provides the key mechanism stabilizing low-temperature skyrmion phases. We show that, for magnetic field directions along the easy anisotropy axes, the phase diagrams feature stable skyrmion pockets for both signs of the anisotropy constant. We further analyze the nature of the transitions at the critical field Hc1, associated with the reorientation of stable and metastable spirals along the field. We also examine the transition at Hc2, where the conical state closes into the homogeneous state accompanied by a deviation of the wave vector from the field direction. By mapping characteristic anisotropy-dependent parameters in the theoretical phase diagrams, we provide guidelines for connecting theory with experiment and for estimating the cubic anisotropy constant in Fe1−xCoxSi and MnSi. Our results indicate that samples Fe1−xCoxSi with small x∼0.1 possess sufficiently strong cubic anisotropy to stabilize a low-temperature skyrmion phase. Overall, these theoretical findings establish a quantitative framework for predicting and interpreting skyrmion stability in other cubic helimagnets as well.

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Phys. Rev. Research 8, 013130– Published 5 February, 2026
  • Received 2 October 2025
  • Accepted 9 January 2026
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