Multipole surface-plasmon modes on simple metals

The average multipole surface-plasmon energy for simple metals, as well as that of ordinary surface and bulk plasmons, is obtained using energy-weighted moments of the electronic response to sufficiently general external perturbations. A local approximation of exchange and correlation effects is use...

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Detalles Bibliográficos
Autores: Sellarès González, Jordi, Barberán Falcón, Núria
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:1994
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/9904
Acceso en línea:https://hdl.handle.net/2445/9904
Access Level:acceso abierto
Palabra clave:Plasmons (Física)
Electrons
Plasmons (Physics)
Descripción
Sumario:The average multipole surface-plasmon energy for simple metals, as well as that of ordinary surface and bulk plasmons, is obtained using energy-weighted moments of the electronic response to sufficiently general external perturbations. A local approximation of exchange and correlation effects is used within a jellium model. Band-structure effects are incorporated through an effective electronic mass. Taking advantage of the transparency of the method, we analyze under what circumstances such modes might be observable. It is shown that due to an interplay between Coulomb and kinetic energies, the multipole modes become unobservable for increasing values of the transferred momentum (q) parallel to the surface. The value of q at which the multipole mode becomes unobservable is much smaller than the cutoff value for Landau damping. The effect of the electronic surface diffuseness is also analyzed. We compare our results with previous density-functional calculations and with recent experimental data for Na, K, and Cs.