Square and rhombic lattices of magnetic skyrmions in a centrosymmetric binary compound

• Published in: Nature communications Vol. 13; no. 1; p. 1472
• Main Authors: Takagi, Rina, Matsuyama, Naofumi, Ukleev, Victor, Yu, Le, White, Jonathan S., Francoual, Sonia, Mardegan, José R. L., Hayami, Satoru, Saito, Hiraku, Kaneko, Koji, Ohishi, Kazuki, Ōnuki, Yoshichika, Arima, Taka-hisa, Tokura, Yoshinori, Nakajima, Taro, Seki, Shinichiro
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 30.03.2022; Nature Publishing Group; Nature Portfolio
• Subjects: 639/301/119/1001; 639/766/119/997; Crystal structure; Dependence; Elastic scattering; Experiments; Fourier transforms; Humanities and Social Sciences; Hypothetical particles; Laboratories; Lattices; Magnetic fields; multidisciplinary; Particle spin; Particle theory; Phase diagrams; Physics; Rare earth compounds; Science; Science (multidisciplinary); Swirling; X-ray scattering
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-022-29131-9

Magnetic skyrmions are topologically stable swirling spin textures with particle-like character, and have been intensively studied as a candidate of high-density information bit. While magnetic skyrmions were originally discovered in noncentrosymmetric systems with Dzyaloshinskii-Moriya interaction, recently a nanometric skyrmion lattice has also been reported for centrosymmetric rare-earth compounds, such as Gd 2 PdSi 3 and GdRu 2 Si 2 . For the latter systems, a distinct skyrmion formation mechanism mediated by itinerant electrons has been proposed, and the search of a simpler model system allowing for a better understanding of their intricate magnetic phase diagram is highly demanded. Here, we report the discovery of square and rhombic lattices of nanometric skyrmions in a centrosymmetric binary compound EuAl 4 , by performing small-angle neutron and resonant elastic X-ray scattering experiments. Unlike previously reported centrosymmetric skyrmion-hosting materials, EuAl 4 shows multiple-step reorientation of the fundamental magnetic modulation vector as a function of magnetic field, probably reflecting a delicate balance of associated itinerant-electron-mediated interactions. The present results demonstrate that a variety of distinctive skyrmion orders can be derived even in a simple centrosymmetric binary compound, which highlights rare-earth intermetallic systems as a promising platform to realize/control the competition of multiple topological magnetic phases in a single material. Typically, skyrmions appear in magnet systems which are non-centrosymmetric. Here, using neutron and X-ray scattering, Takagi et al show the emergence of a skyrmion phase in the centrosymmetric material EuAl 4 . This expands the range of materials potential hosting skyrmions.