二维拓扑反铁磁材料MnBi_(2)Te_(4)中超快磁化率和磁振子动力学的实时观测

作     者：F.Michael Bartram 李梦 刘良洋 许祗铭 王永超 车梦倩 李昊 吴扬 徐勇 张金松 杨硕 杨鲁懿 F.Michael Bartram;Meng Li;Liangyang Liu;Zhiming Xu;Yongchao Wang;Mengqian Che;Hao Li;Yang Wu;Yong Xu;Jinsong Zhang;Shuo Yang;Luyi Yang

作者机构：State Key Laboratory of Low Dimensional Quantum PhysicsDepartment of PhysicsTsinghua UniversityBeijing 100084China Department of PhysicsUniversity of TorontoToronto M5S 1A7Canada Beijing Innovation Center for Future ChipsTsinghua UniversityBeijing 100084China Tsinghua-Foxconn Nanotechnology Research CenterDepartment of PhysicsTsinghua UniversityBeijing 100084China College of Math and PhysicsBeijing University of Chemical TechnologyBeijing 100029China Frontier Science Center for Quantum InformationBeijing 100084China Collaborative Innovation Center of Quantum MatterBeijing 100084China RIKEN Center for Emergent Matter Science(CEMS)WakoSaitama 351-0198Japan Hefei National LaboratoryHefei 230088China 

出 版 物：《Science Bulletin》 (科学通报（英文版）)

年 卷 期：2023年第68卷第22期

页      面：2734-2742,M0005页

核心收录：

学科分类：080801[工学-电机与电器] 0808[工学-电气工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：supported by the National Key R&D Program of China(2020YFA0308800 and 2021YFA1400100) the National Natural Science Foundation of China(12074212) supported by the National Natural Science Foundation of China(12174214 and 92065205) the National Key R&D Program of China(2018YFA0306504) the Innovation Program for Quantum Science and Technology(2021ZD0302100) supported by the National Natural Science Foundation of China(12274252) the National Key R&D Program of China(2018YFA0307100) supported by the National Natural Science Foundation of China(21975140 and 51991343) Fundamental Research Funds for the Central Universities(Buctrc202212) supported by funds from the University of Toronto 

主　　题：2D topological antiferromagnet Ultrafast magnetization dynamics Ultrafast magnon dynamics Spintronics Magnonics Ultrafast spectroscopy 

摘      要：原子级薄的范德华磁性材料不仅为探索二维极限下的基本物理学提供了肥沃的土壤,也为新型超快功能器件创造了巨大的机会.本文系统研究了少层拓扑反铁磁MnBi_(2)Te_(4)晶体在不同层厚、温度和磁场下的超快磁化率和自旋波动力学.作者发现激光诱导的(退)磁化过程可用于精确地跟踪不同磁场区域中的不同磁状态,包括显示出明显的奇偶层数效应.此外,频率为数十千兆赫兹的反铁磁磁振子模式可以被光脉冲激发并在时域中直接被观察到,其频率强烈地依赖于磁场.值得注意的是,磁化率和磁振子动力学不仅可以在时间分辨的磁光克尔效应中观察到,而且在时间分辨的反射率中也可以观察到,这表明磁态和电子结构之间存在很强的相关性.本工作研究了这种新型二维反铁磁体中的超快自旋动力学,为二维反铁磁自旋电子学和磁振子学的潜在应用以及磁态和拓扑量子态的超快调控研究铺平了道路.