Correlated Electron Research Group (CERG) and Cross-Correlated Materials Research Group (CMRG), RIKEN-ASI, Wako 351-0198, Japan.
Nat Commun. 2012;3:988. doi: 10.1038/ncomms1990.
The manipulation of spin textures with electric currents is an important challenge in the field of spintronics. Many attempts have been made to electrically drive magnetic domain walls in ferromagnets, yet the necessary current density remains quite high (10(7) A cm(-2)). A recent neutron study combining Hall effect measurements has shown that an ultralow current density of J10(2) A cm(-2) can trigger the rotational and translational motion of the skyrmion lattice in MnSi, a helimagnet, within a narrow temperature range. Raising the temperature range in which skyrmions are stable and reducing the current required to drive them are therefore desirable objectives. Here we demonstrate near-room-temperature motion of skyrmions driven by electrical currents in a microdevice composed of the helimagnet FeGe, by using in-situ Lorentz transmission electron microscopy. The rotational and translational motions of skyrmion crystal begin under critical current densities far below 100 A cm(-2).
电流操控自旋纹理是自旋电子学领域的一个重要挑战。许多人尝试过通过电流驱动铁磁体中的磁畴壁,但所需的电流密度仍然相当高(约为 10(7) A/cm(-2))。最近的一项结合了霍尔效应测量的中子研究表明,在一个较窄的温度范围内,超低压电流密度 J~10(2) A/cm(-2) 可以引发 MnSi(一种螺旋磁体)中 skyrmion 晶格的旋转和平移运动。因此,提高 skyrmion 稳定的温度范围并降低驱动它们所需的电流是理想的目标。在这里,我们通过使用原位洛伦兹透射电子显微镜,在由螺旋磁体 FeGe 组成的微器件中演示了电流驱动的近室温 skyrmion 运动。在远低于 100 A/cm(-2)的临界电流密度下,skyrmion 晶体的旋转和平移运动开始。