[11p-M101-8~14] 10.2 スピン基盤技術・萌芽的デバイス技術

▲ [11p-M101-11] Magnetization compensation temperature and field-driven domain wall creep motion in ferrimagnetic Tb/CoFeB/MgO layer

〇Yoichi Shiota¹、Yushou Hirata¹、Takaya Okuno¹、Duck-Ho Kim¹、Takahiro Moriyama¹、Teruo Ono¹ (1.ICR Kyoto Univ.)

キーワード：Ferrimagnet, Magnetization compensation temperature, Magnetic domain wall

We studied the magnetization compensation temperature (T_M) and field-driven domain wall creep motion with respect to CoFeB thickness in Tb/CoFeB/MgO layer. Antiferromagnetic coupling between the magnetic moment of Tb and CoFeB leads to a ferrimagnetic behavior in CoFeB/MgO junctions. We found that T_M was increased by decreasing the thickness of CoFeB, which can be explained by the ratio of total magnetic moment of Tb and CoFeB. Field-driven magnetic domain wall (DW) dynamics in a creep region were then investigated using a real-time DW detection method. The faster DW velocity was obtained in thicker CoFeB, which is in contrast to the previously reported results in the ferromagnetic wires.