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arXiv · 2511.21039

Probing magnetic-field-induced multipolar ordering through field-angle-resolved magnetostriction and thermal expansion in PrIr$_2$Zn$_{20}$

Naoki Okamoto·Yohei Kono·Takahiro Onimaru·Keisuke T. Matsumoto·Kazumasa Hattori·Shunichiro Kittaka
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Abstract

We performed field-angle-resolved magnetostriction and thermal-expansion measurements on PrIr$_2$Zn$_{20}$, a cubic non-Kramers compound exhibiting antiferroquadrupolar order below $T_{\rm Q}=0.125$ K. Thermal expansion exhibits two qualitatively different anomalies under magnetic fields applied along the $[001]$ direction, providing experimental support for the existence of an intermediate A phase previously reported. Furthermore, comparison between the experimental results and theoretical modeling indicates a strong anisotropic coupling of the $O_{20}$ quadrupolar moment, which plays a key role in stabilizing the A phase. These findings demonstrate that multipolar states in non-Kramers systems can be effectively tuned by magnetic-field orientation, providing insights into the anisotropic nature of quadrupolar interactions.

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Naoki Okamoto, Yohei Kono, Takahiro Onimaru, Keisuke T. Matsumoto, Kazumasa Hattori, Shunichiro Kittaka. 2025-11-26. Probing magnetic-field-induced multipolar ordering through field-angle-resolved magnetostriction and thermal expansion in PrIr$_2$Zn$_{20}$. https://doi.org/10.1103/5ksm-qhrl

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