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arXiv · 2511.00399

Absence of magnetic order and magnetic fluctuations in RuO$_{2}$

Jiabin Song·Chao Mu·Shilin Zhu·Xuebo Zhou·Wei Wu·Yun-ze Long·Jianlin Luo·Zheng Li
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Abstract

A novel magnetic class blending ferromagnetism and antiferromagnetism, termed altermagnetism, has gained significant attention for its staggered order in coordinate and momentum spaces, time-reversal symmetry-breaking phenomena, and promising applications in spintronics. Ruthenium dioxide (RuO$_{2}$) has been considered a candidate material for altermagnetism, yet the presence of magnetic moments on Ru atoms remains a subject of debate. In this study, we systematically investigated the magnetic properties of RuO$_{2}$ powder using nuclear quadrupole resonance (NQR) measurements. The NQR spectra show that there is no internal magnetic field. Furthermore, the temperature independence of spin-lattice relaxation rate, $1/T_1T$, proves that there are no magnetic fluctuations. Our results unambiguously demonstrate that Ru atoms in RuO$_{2}$ possess neither static magnetic moments nor fluctuating magnetic moments, and thus RuO$_{2}$ does not possess the magnetic characteristics essential for altermagnetism.

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Jiabin Song, Chao Mu, Shilin Zhu, Xuebo Zhou, Wei Wu, Yun-ze Long, Jianlin Luo, Zheng Li. 2025-11-01. Absence of magnetic order and magnetic fluctuations in RuO$_{2}$. https://doi.org/10.1103/cb99-6thg

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