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arXiv · 2006.08865

Antiferromagnetic long-range order in $5d^1$ double-perovskite Sr$_2$MgReO$_6$

Shang Gao·Daigorou Hirai·Hajime Sagayama·Hiroyuki Ohsumi·Zenji Hiroi·Taka-hisa Arima
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Abstract

The double-perovskite A$_2$BB'O$_6$ with heavy transition metal ions on the ordered B' sites is an important family of compounds to study the interplay between electron correlation and spin-orbit coupling (SOC). Here we prepared high-quality Sr$_2$MgReO$_6$ powder and single-crystal samples and performed non-resonant and resonant synchrotron x-ray diffraction experiments to investigate its magnetic ground state. By combining the magnetic susceptibility and heat capacity measurements, we conclude that Sr$_2$MgReO$_6$ exhibits a layered antiferromagnetic (AF) order at temperatures below $\sim$ 55 K with a propagation vector q = (001), which contrasts the previously suspected spin glass state. Our works clarify the magnetic order in Sr$_2$MgReO$_6$ and demonstrate it as a candidate system to look for magnetic octupolar orders and exotic spin dynamics.

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Shang Gao, Daigorou Hirai, Hajime Sagayama, Hiroyuki Ohsumi, Zenji Hiroi, Taka-hisa Arima. 2020-06-16. Antiferromagnetic long-range order in $5d^1$ double-perovskite Sr$_2$MgReO$_6$. https://doi.org/10.1103/physrevb.101.220412

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