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arXiv · 2405.15479

Quasi-two-dimensional ferromagnetism in the triangular magnet EuAl$_{12}$O$_{19}$

G. Bastien·Q. Courtade·A. Eliáš·T. Haidamak·P. Proschek·M. Dušek·J. Priessnitz·P. Baláž·R. H. Colman
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Abstract

We report ferromagnetic ordering at $T_\mathrm {C}=1.3\,$K in the quasi-two dimensional magnet EuAl$_{12}$O$_{19}$ with large spins $S=7/2$. This ferromagnetic state was characterized by magnetization and specific heat measurements and the experimental results were compared with classical Monte Carlo simulations. They reveal a strong single ion anisotropy leading to an uniaxial spontaneous magnetization along the $c$ axis. Furthermore the application of a magnetic field in the hard magnetization plane $ab$ reduces the Curie temperature and it reaches zero temperature at a magnetic field of $\mu_\mathrm{0} H_c \approx 0.5\,$T.

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G. Bastien, Q. Courtade, A. Eliáš, T. Haidamak, P. Proschek, M. Dušek, J. Priessnitz, P. Baláž, R. H. Colman. 2024-05-24. Quasi-two-dimensional ferromagnetism in the triangular magnet EuAl$_{12}$O$_{19}$. https://doi.org/10.1103/physrevb.110.094436

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