Flexible manipulation of local magnetic configurations on the sub-micro scale has long been a pursuit in the field of magnetism science owing to its potential applications in future spintronic devices. This goal can be achieved by using current-induced spin torque to drive the magnetic domain walls. However, the current density threshold of 10^6-10^8 A/cm^2 in metallic systems induced by intrinsic and extrinsic pinning effects increases the energy consumption of the device and limits its application. The marriage between magnetism and topology opens a door for efficient magnetism manipulation, but to date, complex structures (such as multilayer film structures) are still required. Here, we report a unique process of magnetism modulation in the recently discovered magnetic Weyl semimetal Co3Sn2S2 through current-assisted domain wall depinning. Non-adiabatic spin-transfer torques, which are induced by current and significantly modulated by the linear dispersion of Weyl fermions, impose on the local magnetic moments inside the domain walls, leading to a greatly improved efficiency of domain wall motion in magnetic Weyl semimetals compared with conventional metals. By analysing the changes of hysteresis loops under different DC currents, a low current threshold of 1.5*10^5 A/cm^2, and two orders of magnitude improvement of depinning efficiency are obtained in this single material layer. The high efficiency to drive domain walls by current suggests that magnetic Weyl semimetal is a hopeful material system for realizing low-energy consumption spintronic devices.
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