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arXiv · 1712.05504

Neutron Diffraction Study on Single-crystalline UAu${_2}$Si$_2$

Chihiro Tabata·Milan Klicpera·Bachir Ouladdiaf·Hiraku Saito·Michal Vališka·Klára Uhlířová·Naoyuki Miura·Vladimír Sechovský·Hiroshi Amitsuka
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Abstract

Magnetic structure of tetragonal UAu$_2$Si$_2$ was investigated by single-crystal neutron diffraction experiments. Below $T_{\rm N}$ = 20 K it orders antiferromagnetically with a propagation vector of $k = (2/3, 0, 0)$ and magnetic moments of uranium ions pointing along the tetragonal $c$-axis. Weak signs of the presence of a ferromagnetic component of magnetic moment were traced out.Taking into account a group theory calculation and experimental results of magnetization and $^{29}$Si-NMR, the magnetic structure is determined to be a squared-up antiferromagnetic structure, with a stacking sequence ($+ + -$) of the ferromagnetic $ac$-plane sheets along the $a$-axis. This result highlights similar magnetic correlations in UAu$_2$Si$_2$ and isostructural URu$_2$Si$_2$.

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Chihiro Tabata, Milan Klicpera, Bachir Ouladdiaf, Hiraku Saito, Michal Vališka, Klára Uhlířová, Naoyuki Miura, Vladimír Sechovský, Hiroshi Amitsuka. 2017-12-15. Neutron Diffraction Study on Single-crystalline UAu${_2}$Si$_2$. https://doi.org/10.1103/physrevb.96.214442

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