Systematic study of doping effect on the electronic structure of Cu$_{x}$NbSe$_{2}$

ORAL

Abstract

NbSe$_{2}$ is the one of the most studied transition metal dichalcogenide(TMD) materials. It has two phases : superconducting and charge density wave(CDW) phases. The superconductivity in NbSe$_{2}$ is known to be a conventional BCS superconductor. On the other hand, CDW mechanism in NbSe$_{2}$ cannot be explained by the conventional Fermi surface nesting scenario. To find out the exact mechanism of the CDW in NbSe$_{2}$, we try to change the electronic structure of NbSe$_{2}$ by Cu doping. In this presentation, we report the electronic structure studies of the Cu$_{x}$NbSe$_{2}$(x=0, 0.02, 0.04, 0.06, 0.08) measured by angle resolved photoemission spectroscopy (ARPES). We indeed observe doping effects on the electronic structure. The main effect is a Fermi surface topology change, which in turn modifies the nesting condition for CDW phase. To see the nesting condition more clearly, we performed auto-correlation analysis of the data. In addition, we studied the doping and temperature effects on the band renormalization and kink energy.

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Authors

  • Y.K. Kim

    • Insitute of Physics and Applied Physics, Yonsei University
    • Institute of Physics and Applied Physics
    • Institute of Physics and Applied Physics, Yonsei University, Korea

  • Y.Y. Koh

    • Institute of Physics and Applied Physics, Yonsei University, Korea

  • W.S. Jung

    • Institute of Physics and Applied Physics, Yonsei University, Korea

  • G.R. Han

    • Institute of Physics and Applied Physics, Yonsei University, Korea

  • S.R. Park

    • Institute of Physics and Applied Physics, Yonsei University, Korea

  • C.S. Leem

    • Institute of Physics and Applied Physics, Yonsei University, Korea

  • Chul Kim

    • Institute of Physics and Applied Physics, Yonsei University, Korea

  • D.J. Song

    • Institute of Physics and Applied Physics, Yonsei University, Korea

  • W.S. Kyung

    • Institute of Physics and Applied Physics, Yonsei University, Korea

  • H.Y. Choi

    • Institute of Physics and Applied Physics, Yonsei University, Korea

  • L.X. Yang

    • 2Department of Physics, Surface Physics Laboratory(National Key Laboratory) and Advanced Materials Laboratory,Fudan University, P. R. China

  • C. He

    • 2Department of Physics, Surface Physics Laboratory(National Key Laboratory) and Advanced Materials Laboratory,Fudan University, P. R. China

  • F. Chen

    • 2Department of Physics, Surface Physics Laboratory(National Key Laboratory) and Advanced Materials Laboratory,Fudan University, P. R. China

  • D.L. Feng

    • 2Department of Physics, Surface Physics Laboratory(National Key Laboratory) and Advanced Materials Laboratory,Fudan University, P. R. China

  • C. Kim

    • Institute of Physics and Applied Physics, Yonsei University, Seoul, Korea
    • Institute of Physics and Applied Physics, Yonsei University, Korea