Electronic structure of transition metal dichalcogenides PdTe_2 and Cu_(0.05)PdTe_2 superconductors obtained by angle-resolved photoemission spectroscopy  

作　　者：刘艳 赵建洲 俞理 林成天 胡成 刘德发 彭莹莹 谢卓晋 何俊峰 陈朝宇 冯娅 伊合绵 刘旭 赵林 何少龙 刘国东 董晓莉 张君 陈创天 许祖彦 翁虹明 戴希 方忠 周兴江 

机构地区：[1]National Laboratory for Superconductivity,Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences [2]Max-Planck-Institut für Festk rperforschung,Heisenbergstrasse 1,70569 Stuttgart,Germany [3]Technical Institute of Physics and Chemistry,Chinese Academy of Sciences [4]Collaborative Innovation Center of Quantum Matter

出　　处：《Chinese Physics B》2015年第6期100-108,共9页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant No.11190022);the National Basic Research Program of China(Grant Nos.2011CB921703 and 2011CBA00110);the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant No.XDB07020300)

摘　　要：The layered transition metal chalcogenides have been a fertile land in solid state physics for many decades. Various MX2-type transition metal dichalcogenides, such as WTe2, IrTe2, and MoS2, have triggered great attention recently, either for the discovery of novel phenomena or some extreme or exotic physical properties, or for their potential applications. PdTe2 is a superconductor in the class of transition metal dichalcogenides, and superconductivity is enhanced in its Cu- intercalated form, Cuo.05PdTe2. It is important to study the electronic structures of PdTe2 and its intercalated form in order to explore for new phenomena and physical properties and understand the related superconductivity enhancement mecha- nism. Here we report systematic high resolution angle-resolved photoemission （ARPES） studies on PdTe2 and Cuo.05PdTe2 single crystals, combined with the band structure calculations. We present in detail for the first time the complex multi-band Fermi surface topology and densely-arranged band structure of these compounds. By carefully examining the electronic structures of the two systems, we find that Cu-intercalation in PdTe2 results in electron-doping, which causes the band structure to shift downwards by nearly 16 meV in Cuo.05PdTe2. Our results lay a foundation for further exploration and investigation on PdTe2 and related superconductors.The layered transition metal chalcogenides have been a fertile land in solid state physics for many decades. Various MX2-type transition metal dichalcogenides, such as WTe2, IrTe2, and MoS2, have triggered great attention recently, either for the discovery of novel phenomena or some extreme or exotic physical properties, or for their potential applications. PdTe2 is a superconductor in the class of transition metal dichalcogenides, and superconductivity is enhanced in its Cu- intercalated form, Cuo.05PdTe2. It is important to study the electronic structures of PdTe2 and its intercalated form in order to explore for new phenomena and physical properties and understand the related superconductivity enhancement mecha- nism. Here we report systematic high resolution angle-resolved photoemission （ARPES） studies on PdTe2 and Cuo.05PdTe2 single crystals, combined with the band structure calculations. We present in detail for the first time the complex multi-band Fermi surface topology and densely-arranged band structure of these compounds. By carefully examining the electronic structures of the two systems, we find that Cu-intercalation in PdTe2 results in electron-doping, which causes the band structure to shift downwards by nearly 16 meV in Cuo.05PdTe2. Our results lay a foundation for further exploration and investigation on PdTe2 and related superconductors.

关 键 词：transition metal dichalcogenides PdTe2 SUPERCONDUCTOR PHOTOEMISSION 

分 类 号：O511.3[一般工业技术—材料科学与工程]