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arXiv · 2210.05099

New Gd-based magnetic compound GdPt$_2$B with a chiral crystal structure

Yoshiki J. Sato·Hikari Manako·Yoshiya Homma·Dexin Li·Ryuji Okazaki·Dai Aoki
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Abstract

Herein, we report the discovery of a novel Gd-based magnetic compound GdPt$_2$B with a chiral crystal structure. X-ray diffraction and chemical composition analyses reveal a CePt$_2$B-type crystal structure (space group: $P6_422$) for GdPt$_2$B. Moreover, we successfully grew single crystals of GdPt$_2$B using the Czochralski method. Magnetization measurements and the Curie$-$Weiss analysis demonstrate that the ferromagnetic interaction is dominant in GdPt$_2$B. A clear transition is observed in the temperature dependence of electrical resistivity, magnetic susceptibility, and specific heat at $T_{\rm O}$ = 87 K. The magnetic phase diagram of GdPt$_2$B, which consists of a field-polarized ferromagnetic region and a magnetically ordered region, resembles those of known chiral helimagnets. Furthermore, magnetic susceptibility measurements reveal a possible spin reorientation within the magnetically ordered phase in magnetic fields perpendicular to the screw axis. The results demonstrate that GdPt$_2$B is a suitable platform for investigating the competing effects of ferromagnetic and antisymmetric exchange interactions in rare-earth-based chiral compounds.

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Yoshiki J. Sato, Hikari Manako, Yoshiya Homma, Dexin Li, Ryuji Okazaki, Dai Aoki. 2022-10-11. New Gd-based magnetic compound GdPt$_2$B with a chiral crystal structure. https://doi.org/10.1103/physrevmaterials.6.104412

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