摘要
具有Kagome晶格的晶体有很多有趣的性质,包括受挫磁阻、电荷有序、拓扑态、超导和关联现象.为了在电子学和自旋电子学应用中实现高性能Kagome晶格化合物,需要对能带结构仔细调整.本文采用输运测量、角分辨光电子能谱和从头计算等方法研究了Kagome晶格晶体Ni_(3)In_(2)S_(2)的电子结构.输运测量表明,Ni_(3)In_(2)S_(2)是一种在Kagome晶格材料中具有创纪录的高载流子迁移率(空穴和电子迁移率分别约为8683和7356 cm^(2)V^(-1)S^(-1))和极大磁电阻(在2 K和13 T时为15,518%)的补偿半金属.Ni在Kagome晶格中的3d电子导致的非直接带隙、小的电子/空穴口袋和大的带宽的能带结构特征很好地解释了这些特殊的性质.这项工作表明,晶体场和掺杂是优化Kagome晶格晶体输运特性的关键因素.我们的工作为Kagome晶格半金属在电子学和自旋电子学方面的应用提供了材料基础和优化路径.
The kagome-lattice crystal hosts various intriguing properties including the frustrated magnetism,charge order,topological state,superconductivity and correlated phenomena.To achieve high-performance kagome-lattice compounds for electronic and spintronic applications,careful tuning of the band structure would be desired.Here,the electronic structures of kagome-lattice crystal Ni_(3)In_(2)S_(2) were investigated by transport measurements,angle-resolved photoemission spectroscopy as well as ab initio calculations.The transport measurements reveal Ni_(3)In_(2)S_(2) as a compensated semimetal with record-high carrier mobility(~8683 and 7356 cm^(2) V^(−1) S^(−1) for holes and electrons)and extreme magnetoresistance(15,518%at 2 K and 13 T)among kagome-lattice materials.These extraordinary properties are well explained by its band structure with indirect gap,small electron/hole pockets and large bandwidth of the 3d electrons of Ni on the kagome lattice.This work demonstrates that the crystal field and doping serve as the key tuning knobs to optimize the transport properties in kagome-lattice crystals.Our work provides material basis and optimization routes for kagome-lattice semimetals towards electronics and spintronics applications.
作者
房红伟
吕孟
苏豪
袁健
李一苇
徐丽璇
刘帅
魏立阳
刘馨琪
杨海峰
姚岐
王美晓
郭艳峰
史武军
陈宇林
刘恩克
柳仲楷
Hongwei Fang;Meng Lyu;Hao Su;Jian Yuan;Yiwei Li;Lixuan Xu;Shuai Liu;Liyang Wei;Xinqi Liu;Haifeng Yang;Qi Yao;Meixiao Wang;Yanfeng Guo;Wujun Shi;Yulin Chen;Enke Liu;Zhongkai Liu(School of Physical Science and Technology,ShanghaiTech University,Shanghai 201210,China;University of Chinese Academy of Sciences,Beijing 100049,China;Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China;State Key Laboratory of Low Dimensional Quantum Physics,Department of Physics,Tsinghua University,Beijing 100084,China;ShanghaiTech Laboratory for Topological Physics,ShanghaiTech University,Shanghai 201210,China;Center for Transformative Science,ShanghaiTech University,Shanghai 201210,China;Shanghai High Repetition Rate XFEL and Extreme Light Facility(SHINE),ShanghaiTech University,Shanghai 201210,China;Department of Physics,University of Oxford,Oxford OX13PU,United Kingdom)
基金
supported by the National Key R&D Program of China(2017YFA0305400 and 2019YFA0704900)
Chinese Academy of Sciences-Shanghai Science Research Center(CAS-SSRC-YH2015-01)
Double First-Class Initiative Fund of Shanghai Tech University
the support from the Engineering and Physical Sciences Research Council Platform Grant(EP/M020517/1)
the Major Research Plan of the National Natural Science Foundation of China(NSFC,92065201)
Shanghai Municipal Science and Technology Major Project(2018SHZDZX02)
the support from the NSFC(52088101 and 11974394)
the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(XDB33000000)
the support from Shanghai Committee of Science and Technology(22ZR1441800)
Shanghai-XFEL Beamline Project(SBP)(31011505505885920161A2101001)
the support from the NSFC(12004248)and the support from the NSFC(12104304)
Shanghai Sailing Program(20YF1430500)。
