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arXiv · 2411.15969

Spin amplitude wave due to dipole-quadrupole hybridization in spin-1 pyrochlore magnets

Hiroki Nakai·Chisa Hotta
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Abstract

We explore the quantum pseudospin-1 pyrochlore magnet featuring Fe$^{2+}$-based spinel oxides that addresses the formation of amplitude-modulated spin-density waves. We propose that the relatively small spin-orbit coupling and the small extra crystal field splitting in these materials create anisotropic exchange interactions and strong single-ion anisotropy, respectively, whose interplay becomes the source of quadrupolar moments selectively appearing on certain sublattices, leading to a spatially modulated hybrid of dipolar and quadrupolar moments. This mechanism represents the possibility of insulating magnets to form an exotic phase with coexisting liquid-solid properties.

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Hiroki Nakai, Chisa Hotta. 2024-11-24. Spin amplitude wave due to dipole-quadrupole hybridization in spin-1 pyrochlore magnets. https://doi.org/10.1103/lg4b-152s

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