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arXiv · 2201.07356

In-plane magnetic structure and exchange interactions in the high-temperature antiferromagnet Cr2Al

Chengxi Zhao·Kisung Kang·Joerg C. Neuefeind·Andre Schleife·Daniel P. Shoemaker
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Abstract

The ordered tetragonal intermetallic Cr$_2$Al forms the same structure type as Mn$_2$Au, and the latter has been heavily investigated for its potential in antiferromagnetic spintronics due to its degenerate in-plane N\'{e}el vector. We present the single crystal flux growth of Cr$_2$Al and orientation-dependent magnetic properties. Powder neutron diffraction of Cr$_2$Al and first-principles simulations reveal that the magnetic ordering is likely in-plane and therefore identical to Mn$_2$Au, providing a second material candidate in the MoSi$_2$ structure type to evaluate the fundamental interactions that govern spintronic effects. The single ordering transition seen in thermal analysis and resistivity indicates that no canting of the moments along the $c$ axis is likely. Magnetometry, resistivity, and differential scanning calorimetry measurements confirm the N\'{e}el temperature to be $634 \pm 2$ K. First-principles simulations indicate that the system has a small density of states at the Fermi energy and confirm the lowest-energy magnetic ground state ordering, while Monte Carlo simulations match the experimental N\'{e}el temperature.

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Chengxi Zhao, Kisung Kang, Joerg C. Neuefeind, Andre Schleife, Daniel P. Shoemaker. 2022-01-18. In-plane magnetic structure and exchange interactions in the high-temperature antiferromagnet Cr2Al. https://doi.org/10.1103/physrevmaterials.5.084411

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