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Magnetic skyrmion lattice disclinations in pentagon- and heptagon-shaped FeGe nanostructures

Thibaud Denneulin1,*, Nikolai S. Kiselev2, Vladyslav M. Kuchkin3, and Rafal E. Dunin-Borkowski1

  • *Contact author: t.denneulin@fz-juelich.de
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Phys. Rev. B 114, 024411 – Published 7 July, 2026

DOI: https://doi.org/10.1103/nwd2-1hk9

Abstract

Magnetic skyrmions in chiral magnets typically arrange into hexagonal lattices, with their structural order influenced by factors such as temperature, external magnetic fields, and geometric constraints. While translational defects in skyrmion lattices such as dislocations have been extensively studied, individual angular defects, or disclinations, remain largely unexplored. Here, we report on the stabilization of fivefold and sevenfold disclinations in pentagon- and heptagon-shaped FeGe single-crystal nanostructures created using focused ion beam milling. The magnetic and elastic structures of the disclinated lattices are investigated using Fresnel imaging and off-axis electron holography in a transmission electron microscope. The results are supported by micromagnetic simulations and analytical models based on linear elasticity theory.

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synopsis

Stabilizing Magnetic Defects

Published 7 July, 2026

Researchers have shown that defects in lattices of magnetic quasiparticles called skyrmions can be created, stabilized, and manipulated.

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Phys. Rev. B 114, 024411– Published 7 July, 2026
  • Received 11 January 2026
  • Revised 29 April 2026
  • Accepted 12 May 2026
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