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arXiv · 2304.14896

The Double-$Q$ Ground State with Topological Charge Stripes in the Skyrmion Candidate $\text{GdRu}_{\text{2}}\text{Si}_{\text{2}}$

G. D. A. Wood·D. D. Khalyavin·D. A. Mayoh·J. Bouaziz·A. E. Hall·S. J. R. Holt·F. Orlandi·P. Manuel·S. Blügel·J. B. Staunton·O. A. Petrenko·M. R. Lees·G. Balakrishnan
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Abstract

$\text{GdRu}_{\text{2}}\text{Si}_{\text{2}}$ is a centrosymmetric magnet in which a skyrmion lattice has recently been discovered. Here, we investigate the magnetic structure of the zero field ground state using neutron diffraction on single crystal and polycrystalline $^{\text{160}}\text{GdRu}_{\text{2}}\text{Si}_{\text{2}}$. In addition to observing the principal propagation vectors $\mathbf{q}_{1}$ and $\mathbf{q}_{2}$, we discover higher order magnetic satellites, notably $\mathbf{q}_{1} + 2\mathbf{q}_{2}$. The appearance of these satellites are explained within the framework of a new double-$Q$ constant-moment solution. Using powder diffraction we implement a quantitative refinement of this model. This structure, which contains vortexlike motifs, is shown to have a one-dimensional topological charge density.

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G. D. A. Wood, D. D. Khalyavin, D. A. Mayoh, J. Bouaziz, A. E. Hall, S. J. R. Holt, F. Orlandi, P. Manuel, S. Blügel, J. B. Staunton, O. A. Petrenko, M. R. Lees, G. Balakrishnan. 2023-04-28. The Double-$Q$ Ground State with Topological Charge Stripes in the Skyrmion Candidate $\text{GdRu}_{\text{2}}\text{Si}_{\text{2}}$. https://doi.org/10.1103/physrevb.107.l180402

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