Yu X Z, Morikawa D, Nakajima K, Shibata K, Kanazawa N, Arima T, Nagaosa N, Tokura Y
RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198, Japan.
Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan.
Sci Adv. 2020 Jun 17;6(25):eaaz9744. doi: 10.1126/sciadv.aaz9744. eCollection 2020 Jun.
Nanometer-scale skyrmions are prospective candidates for information bits in low-power consumption devices owing to their topological nature and controllability with low current density. Studies on skyrmion dynamics in different classes of materials have exploited the topological Hall effect and current-driven fast motion of skyrmionic bubbles. However, the small current track motion of a single skyrmion and few-skyrmion aggregates remains elusive. Here, we report the tracking of creation and extinction and motion of 80-nm-size skyrmions upon directional one-current pulse excitations at low current density of the order of 10 A m in designed devices with the notched hole. The Hall motion of a single skyrmion and the torque motions of few-skyrmion aggregates have been directly revealed. The results exemplify low-current density controls of skyrmions, which will pave the way for the application of skyrmions.
由于其拓扑性质以及在低电流密度下的可控性，纳米级斯格明子有望成为低功耗设备中信息比特的候选者。对不同类型材料中斯格明子动力学的研究利用了拓扑霍尔效应和斯格明子气泡的电流驱动快速运动。然而，单个斯格明子和少数斯格明子聚集体的小电流轨道运动仍然难以捉摸。在此，我们报告了在具有缺口孔的设计器件中，在低电流密度（约10 A/m量级）的定向单电流脉冲激发下，对80纳米尺寸斯格明子的产生、湮灭和运动的跟踪。单个斯格明子的霍尔运动和少数斯格明子聚集体的转矩运动已被直接揭示。这些结果例证了斯格明子的低电流密度控制，这将为斯格明子的应用铺平道路。
