(1.School of Integrated Circuit Science & Engineering, Beihang University, Beijing 100191, China) (2.School of Electronic and Information Engineering, Beihang University, Beijing 100191, China) (3.Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000, China）
Voltage induced surface acoustic wave (SAW) is a hot research topic for manipulating magnetic properties in spintronics, due to its characteristics of high efficiency, low power consumption and long propagation distance. The ferrimagnet has attracted much attentions due to its fast magnetic domain wall (DW) motion. The study of its DW motion assisted by SAW is of great significance for the magnetic memory and DW logic devices. Here, we chose ferrimagnetic CoTb film with perpendicular magnetic anisotropy, and fabricated the coupled device of the SAW and Hall bar structure. The coercive fields and DW motion in CoTb film under SAW are explored by magneto-optical Kerr microscopy. We found the coercive fields reduced by 10% in CoTb film system, which is mainly originated from the reduction of the nucleation and propagation fields under the SAW. Furthermore, we observed the DW motion speed increased up to 76% with the assistance of the SAW, which reached 3683 μm/s. Our work has successfully realized the rapid DW motion driven by SAW in the ferrimagnetic system, which provides an alternative to the future low-consumption spintronic devices.