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Updated: Aug 30, 2026

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
Strong energy dependence of the electron-phonon coupling strength on Bi(100)
J E Gayone1, S V Hoffmann, Z Li
1Institute for Storage Ring Facilities, University of Aarhus, DK-8000 Aarhus C, Denmark.
Abstract:
We have studied the energy dependence of the electron-phonon coupling strength on Bi(100). A fit of the temperature-dependent surface state linewidth results in a change of the coupling parameter lambda from 0.20+/-0.02 to 0.72+/-0.05 as the binding energy of the surface state increases from 70 to 330 meV. This result cannot be reconciled with the usual interpretation of lambda as the electron-phonon mass enhancement parameter at the Fermi energy. We suggest that this behavior is mainly caused by the strong energy dependence of the bulk density of states in this region.
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