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arXiv · 2111.09661

Interplay between quadrupolar and magnetic interactions in 5$d^{1}$ double perovskite Ba$_2$MgReO$_6$ under pressure

Hiroto Arima·Yoshiaki Oshita·Daigorou Hirai·Zenji Hiroi·Kazuyuki Matsubayashi
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Abstract

We measured the electrical resistivity, AC magnetic susceptibility, and specific heat of the cubic double perovskite Ba$_2$MgReO$_6$ under pressure. The application of pressure leads to a gradual increase in the transition temperature to the canted antiferromagnetic order, while the quadrupolar order is suppressed above 5 GPa, at which a collinear antiferromagnetic state appears. The obtained unit cell volume-temperature phase diagram for the compound as well as the related compounds suggests that Ba$_2$MgReO$_6$ exists near the phase boundary between the noncollinear and the collinear antiferromagnetic order with multipole decrees of freedom.

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Hiroto Arima, Yoshiaki Oshita, Daigorou Hirai, Zenji Hiroi, Kazuyuki Matsubayashi. 2021-11-18. Interplay between quadrupolar and magnetic interactions in 5$d^{1}$ double perovskite Ba$_2$MgReO$_6$ under pressure. https://doi.org/10.7566/jpsj.91.013702

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