Enhancement of domain-wall mobility detected by NMR at the angular momentum compensation temperature

角運動量補償温度でNMRにより検知した磁壁移動度が向上

今井 正樹  ; 中堂 博之 ; 松尾 衛; 前川 禎通; 齊藤 英治

Imai, Masaki; Chudo, Hiroyuki; Matsuo, Mamoru; Maekawa, Sadamichi; Saito, Eiji

The angular momentum compensation temperature of ferrimagnets has attracted much attention because of high-speed magnetic dynamics near . We show that NMR can be used to investigate domain wall dynamics near in ferrimagnets. We performed Fe-NMR measurements on the ferrimagnet HoFeO with = 245 K. In a multi-domain state, the NMR signal is enhanced by domain wall motion. We found that the NMR signal enhancement shows a maximum at in the multi-domain state. The NMR signal enhancement occurs due to increasing domain-wall mobility toward . We develop the NMR signal enhancement model involves domain-wall mobility. Our study shows that NMR in multi-domain state is a powerful tool to determine , even from a powder sample and it expands the possibility of searching for angular momentum-compensated materials.