The 20-nm Skyrmion Generated at Room Temperature by Spin-Orbit Torques  

作　　者：Jiahao Liu Zidong Wang Teng Xu Hengan Zhou Le Zhao Soong-Guen Je Mi-Young Im Liang Fang Wanjun Jiang 刘嘉豪;王子东;许腾;周恒安;赵乐;Soong-Guen Je;Mi-Young Im;方粮;江万军(State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics,Tsinghua University,Beijing 100084,China;Frontier Science Center for Quantum Information,Tsinghua University,Beijing 100084,China;Institute for Quantum Information&State Key Laboratory of High Performance Computing,College of Computer,National University of Defense Technology,Changsha 410073,China;Center for X-ray Optics,Lawrence Berkeley National Laboratory,Cyclotron Road,Berkeley,CA 94720,USA;Department of Physics,Chonnam National University,Gwangju,61186,Republic of Korea)

机构地区：[1]State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics,Tsinghua University,Beijing 100084,China [2]Frontier Science Center for Quantum Information,Tsinghua University,Beijing 100084,China [3]Institute for Quantum Information&State Key Laboratory of High Performance Computing,College of Computer,National University of Defense Technology,Changsha 410073,China [4]Center for X-ray Optics,Lawrence Berkeley National Laboratory,Cyclotron Road,Berkeley,CA 94720,USA [5]Department of Physics,Chonnam National University,Gwangju,61186,Republic of Korea

出　　处：《Chinese Physics Letters》2022年第1期40-45,共6页中国物理快报（英文版）

基　　金：supported by the Basic Science Center Project of NSFC (Grant No. 51788104);the National Key R&D Program of China (Grant No. 2017YFA020620);the Beijing Natural Science Foundation (Grant No. Z190009);the National Key R&D Program of China (Grant No. 2018YFB1003304);the National Natural Science Foundation of China (Grant Nos. 11774194,51831005, 11861131008, 11804182, and 61832007);the Tsinghua University Initiative Scientific Research Program and the Beijing Advanced Innovation Center for Future Chip (ICFC) supported by U.S. Department of Energy (DE-AC02-05CH11231);by Lawrence Berkeley National Laboratory through the Laboratory Directed Research and Development (LDRD) Program。

摘　　要：The discovery of magnetic skyrmions provides a promising pathway for developing functional spintronic memory and logic devices. Towards the future high-density memory application, nanoscale skyrmions with miniaturized diameters, ideally down to 20 nm are required. Using x-ray magnetic circular dichroism transmission microscopy,nanoscale skyrmions are observed in the [Pt/Co/Ir]15 multilayer at room temperature. In particular, small skyrmions with minimum diameters approaching 20 nm could be generated by the current-induced spin-orbit torques. Through implementing material specific parameters, the dynamic process of skyrmion generation is further investigated by performing micromagnetic simulations. According to the simulation results, we find that both the tube-like Neel-type skyrmions and the bobber-like Neel-type skyrmions can be electrically generated. In particular, the size of the bobber-like Neel-type skyrmions can be effectively reduced by the spin-orbit torques,which leads to the formation of 20 nm Neel-type skyrmions. Our findings could be important for understanding the formation dynamics of nanoscale Neel-type spin textures, skyrmions and bobber in particular, which could also be useful for promoting nanoscale skyrmionic memories and logic devices.

关 键 词：temperature DIAMETERS APPROACHING 

分 类 号：O469[理学—凝聚态物理]