[18a-131-1~10] 10.1 新物質・新機能創成（作製・評価技術）

▼ [18a-131-6] Ultrafast STT-driven domain wall motion in Mn₄N microstrips

〇Toshiki Gushi^1,2、Laurent Vila²、Jean-Philippe Attane²、Olivier Fruchart²、Alain Marty²、Stefania Pizzini³、Jan Vogel³、Matic Klug⁴、Jose Pena-Garcia³、Akihito Anzai¹、Taro Komori¹、Takashi Suemasu¹ (1.Univ. of Tsukuba、2.SPINTEC、3.Institut Neel、4.Kiel Univ.)

キーワード：Domain wall motion, Mn4N, Ferrimagnet

We were interested in Mn₄N thin film as a new candidate for spintronic material and evaluated the current-induced domain wall motion (CIDWM) properties. Mn₄N is expected to achieve ultrafast domain wall (DW) motion with small current density thanks to the small spontaneous magnetization and perpendicular magnetic anisotropy. In this work, we injected current pulses into 1 and 2-µm-wide Mn₄N strips and achieved ultrafast DW motion over 900 m/s with only 1.3 TA/m² current. This result is one of the highest velocity reported, even compared with SOT-assisted systems and presents the potential of Mn₄N as a rare-earth free candidate for CIDWM application.