Electronic Structure of Transition Metal Dichalcogenides PdTe2 and Cu0.05PdTe2 Superconductors Obtained by Angle-Resolved Photoemission Spectroscopy

Yan Liu; Jianzhou Zhao; Li Yu; Chengtian Lin; Cheng Hu; Defa Liu; Yingying Peng; Zhuojin Xie; Junfeng He; Chaoyu Chen; Ya Feng; Hemian Yi; Xu Liu; Lin Zhao; Shaolong He; Guodong Liu; Xiaoli Dong; Jun Zhang; Chuangtian Chen; Zuyan Xu; Hongming Weng; Xi Dai; Zhong Fang; X. J. Zhou

arXiv · 1505.06641

Electronic Structure of Transition Metal Dichalcogenides PdTe2 and Cu0.05PdTe2 Superconductors Obtained by Angle-Resolved Photoemission Spectroscopy

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Abstract

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, Cu0.05PdTe2. 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 mechanism. Here we report systematic high resolution angle-resolved photoemission (ARPES) studies on PdTe2 and Cu0.05$PdTe2 single crystals, combined with the band structure calculations. We present for the first time in detail 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 Cu0.05PdTe2. Our results lay a foundation for further exploration and investigation on PdTe2 and related superconductors.

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Yan Liu, Jianzhou Zhao, Li Yu, Chengtian Lin, Cheng Hu, Defa Liu, Yingying Peng, Zhuojin Xie, Junfeng He, Chaoyu Chen, Ya Feng, Hemian Yi, Xu Liu, Lin Zhao, Shaolong He, Guodong Liu, Xiaoli Dong, Jun Zhang, Chuangtian Chen, Zuyan Xu, Hongming Weng, Xi Dai, Zhong Fang, X. J. Zhou. 2015-05-25. Electronic Structure of Transition Metal Dichalcogenides PdTe2 and Cu0.05PdTe2 Superconductors Obtained by Angle-Resolved Photoemission Spectroscopy. https://arxiv.org/abs/1505.06641

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