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Quasi-Particle Spectra, Charge-Density-Wave, Superconductivity and Electron-Phonon Coupling in 2H-NbSe2

T. Valla·A. V. Fedorov·P. D. Johnson·P-A. Glans·C. McGuinness·K. E. Smith·E. Y. Andrei·H. Berger
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Abstract

High-resolution photoemission has been used to study the electronic structure of the charge density wave (CDW) and superconducting (SC) dichalcogenide, 2H- NbSe2. From the extracted self-energies, important components of the quasiparticle (QP) interactions have been identified. In contrast to previously studied TaSe2, the CDW transition does not affect the electronic properties significantly. The electron-phonon coupling is identified as a dominant contribution to the QP self-energy and is shown to be very anisotropic (k-dependent) and much stronger than in TaSe2.

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T. Valla, A. V. Fedorov, P. D. Johnson, P-A. Glans, C. McGuinness, K. E. Smith, E. Y. Andrei, H. Berger. 2003-12-17. Quasi-Particle Spectra, Charge-Density-Wave, Superconductivity and Electron-Phonon Coupling in 2H-NbSe2. https://doi.org/10.1103/physrevlett.92.086401

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