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arXiv · 2210.02754

Site Split of Antiferromagnetic $\alpha$-Mn Revealed by $^{55}$Mn Nuclear Magnetic Resonance

Masahiro Manago·Gaku Motoyama·Shijo Nishigori·Kenji Fujiwara·Katsuki Kinjo·Shunsaku Kitagawa·Kenji Ishida·Kazuto Akiba·Shingo Araki·Tatsuo C. Kobayashi·Hisatomo Harima
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Abstract

The magnetic structure of antiferromagnetic $\alpha$-Mn has been unclarified for almost 70 years since its magnetism was discovered. We measured the zero-field nuclear magnetic resonance spectra of antiferromagnetic $\alpha$-Mn to obtain further insight into magnetism below $T_{\text{N}} = 95$ K. The site II spectra split into two sites with five subpeaks owing to quadrupole interaction, and this shows that the ordered moments at site II are slightly tilted from the $[001]$ direction. The site III spectra revealed that this site splits into four sites below $T_{\text{N}}$. These findings clearly demonstrate that the antiferromagnetic $\alpha$-Mn symmetry is lower than previously considered.

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Masahiro Manago, Gaku Motoyama, Shijo Nishigori, Kenji Fujiwara, Katsuki Kinjo, Shunsaku Kitagawa, Kenji Ishida, Kazuto Akiba, Shingo Araki, Tatsuo C. Kobayashi, Hisatomo Harima. 2022-10-06. Site Split of Antiferromagnetic $\alpha$-Mn Revealed by $^{55}$Mn Nuclear Magnetic Resonance. https://doi.org/10.7566/jpsj.91.113701

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