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Surface-State Localization at Adatoms

L. Limot·E. Pehlke·J. Kroeger·R. Berndt
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Abstract

Low-temperature scanning tunneling spectroscopy of magnetic and non-magnetic metal atoms on Ag(111) and on Cu(111) surfaces reveals the existence of a common electronic resonance at an energy below the binding energies of the surface states. Using an extended Newns-Anderson model, we assign this resonance to an adsorbate-induced bound state, split off from the bottom of the surface-state band, and broadened by the interaction with bulk states. A lineshape analysis of the bound state indicates that native adatoms decrease the surface-state lifetime, while a cobalt adatom causes no significant change.

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L. Limot, E. Pehlke, J. Kroeger, R. Berndt. 2004-05-18. Surface-State Localization at Adatoms. https://doi.org/10.1103/physrevlett.94.036805

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