講演情報
[10p-PB3-30]Highly efficient current-induced domain wall motion in a room temperature van der Waals magnet
〇(D)Yufeng Wu1, Yicheng Guan1, Yan Zhang1, Jae-Chun Jeon1, Wenjie Zhang1, Ke Xiao1, Stuart Parkin1 (1.Max Planck Institute)
キーワード：
spintronic、Van der Waals Magnet、Domain Wall Motion
Two-dimensional (2D) van der Waals (vdW) magnets provide a promising platform for next-generation spintronic devices owing to their atomically smooth interfaces, reduced defect density, and tunable magnetic properties. Among them, Fe3GaTe2 (FGaT) has attracted significant attention because of its robust ferromagnetism above room temperature and strong perpendicular magnetic anisotropy. Here, we demonstrate highly efficient current-induced domain wall motion (CIDWM) in FGaT racetrack devices over a broad temperature range from 50 K to room temperature. Domain walls are driven by spin-transfer torque (STT) with an ultra-low threshold current density of only a few MA cm-2 and exhibit record-high velocities reaching ~25 m s-7 at low temperatures, representing the fastest domain wall motion reported so far in a vdW magnetic material. Compared with conventional ferromagnetic thin-film systems, FGaT shows significantly reduced pinning and enhanced domain-wall mobility, which are attributed to the structural perfection of the layered vdW crystal. To elucidate the driving mechanism, spin polarization was directly measured using superconducting point-contact spectroscopy. Combined with a one-dimensional STT model, the results reveal a large non-adiabatic torque contribution with β/α > 1, indicating exceptionally efficient angular momentum transfer from conduction electrons to domain walls.Leveraging this highly efficient domain-wall transport, we further realize an electrically readable racetrack memristor based on precise domain-wall positioning. The device demonstrates multilevel resistance states corresponding to more than four data bits while operating at remarkably low current densities. These results establish Fe3GaTe2 as a compelling vdW spintronic material and highlight the potential of vdW racetrack devices for low-power memory, neuromorphic computing, and cryogenic spintronic applications.