Relativistic force between fast electrons and planar targets

The full retarded electromagnetic force experienced by swift electrons moving parallel to planar boundaries is revisited, for both metallic and dielectric targets, with special emphasis on the consequences in electron microscopy experiments. The focus is placed on the sign of the transverse force ex...

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Detalles Bibliográficos
Autores: Rivacoba Ochoa, Alberto Luis, Zabala Unzalu, Miren Nerea
Tipo de recurso: artículo
Fecha de publicación:2014
País:España
Institución:Universidad del País Vasco
Repositorio:Addi. Archivo Digital para la Docencia y la Investigación
OAI Identifier:oai:addi.ehu.eus:10810/16289
Acceso en línea:http://hdl.handle.net/10810/16289
Access Level:acceso abierto
Palabra clave:electromagnetic force
electron beams
surface plasmon
dielectric function
cherenkov radiation
energy-loss
microscopy
exceitations
surfaces
media
beam
PHYSICS AND ASTRONOMY
Descripción
Sumario:The full retarded electromagnetic force experienced by swift electrons moving parallel to planar boundaries is revisited, for both metallic and dielectric targets, with special emphasis on the consequences in electron microscopy experiments. The focus is placed on the sign of the transverse force experienced by the electron beam as a function of the impact parameter. For point probes, the force is found to be always attractive. The contribution of the induced magnetic field and the causality requirements of the target dielectric response, given by the Kramers-Kronig (K-K) relations, prove to be crucial issues at small impact parameters. For spatially extended probes, repulsive forces are predicted for close trajectories, in agreement with previous works. The force experienced by the target is also explored, with the finding that in insulators, the momentum associated to Cherenkov radiation (CR) is relevant at large impact parameters.