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Novel low-energy collective excitation at metal surfaces

V. M. Silkin·A. Garcia-Lekue·J. M. Pitarke·E. V. Chulkov·E. Zaremba·P. M. Echenique
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Abstract

A novel collective excitation is predicted to exist at metal surfaces where a two-dimensional surface-state band coexists with the underlying three-dimensional continuum. This is a low-energy acoustic plasmon with linear dispersion at small wave vectors. Since new modern spectroscopies are especially sensitive to surface dynamics near the Fermi level, the existence of surface-state induced acoustic plasmons is expected to play a key role in a large variety of new phenomena and to create situations with potentially new physics.

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V. M. Silkin, A. Garcia-Lekue, J. M. Pitarke, E. V. Chulkov, E. Zaremba, P. M. Echenique. 2004-02-10. Novel low-energy collective excitation at metal surfaces. https://doi.org/10.1209/epl%2Fi2003-10184-1

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