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Experimental studies of ions and atoms interaction with insulating surface; Etude experimentale de l'interaction rasante d'atomes et d'ions sur des surfaces isolantes

Abstract

Grazing collisions (<3 deg.) of keV ions and atoms: H{sup +}, Ne{sup +}, Ne{sup 0}, Na{sup +} on LiF (001) single crystal, an ionic insulator, are investigated by a time of flight technique. The incident beam is chopped and the scattered particles are collected on a position sensitive detector providing differential cross section while the time of flight gives the energy loss. Deflection plates allow the charge state analysis. Secondary electrons are detected in coincidence allowing direct measurements of electron emission yield, angular and energetic distribution through time of flight measurements. The target electronic structure characterized by a large band gap, governs the collisional processes: charge exchange, electronic excitations and electron emission. In particular, these studies show that the population of local target excitations surface excitons is the major contribution to the kinetic energy transfer (stopping power). Auger neutralization of Ne{sup +} and He{sup +} ions reveals the population of quasi-molecular excitons, an exciton bound on two holes. Referenced in the literature as trion. A direct energy balance determines the binding energy associated with these excited states of the surface. Besides these electronic energy loss processes, two nuclear energy loss mechanisms are characterized. These processes imply momentum transfer to individual  More>>
Authors:
Publication Date:
Oct 15, 2000
Product Type:
Thesis/Dissertation
Report Number:
FRNC-TH-6997
Resource Relation:
Other Information: TH: These physique; 117 refs.; Also available from Bibliotheque universitaire de Sciences, Domaine universitaire Batiment 407, 91405 - Orsay Cedex (France)
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AUGER EFFECT; BEAM NEUTRALIZATION; CHARGE EXCHANGE; ELASTIC SCATTERING; ELECTRON EMISSION; ENERGY LOSSES; EXCITONS; ION-ATOM COLLISIONS; SECONDARY EMISSION; SURFACES
OSTI ID:
20873620
Research Organizations:
Paris-11 Univ., 91 - Orsay (France)
Country of Origin:
France
Language:
French
Other Identifying Numbers:
TRN: FR0700012041634
Availability:
Available from INIS in electronic form
Submitting Site:
FRN
Size:
154 pages
Announcement Date:
Jun 06, 2007

Citation Formats

Villette, J. Experimental studies of ions and atoms interaction with insulating surface; Etude experimentale de l'interaction rasante d'atomes et d'ions sur des surfaces isolantes. France: N. p., 2000. Web.
Villette, J. Experimental studies of ions and atoms interaction with insulating surface; Etude experimentale de l'interaction rasante d'atomes et d'ions sur des surfaces isolantes. France.
Villette, J. 2000. "Experimental studies of ions and atoms interaction with insulating surface; Etude experimentale de l'interaction rasante d'atomes et d'ions sur des surfaces isolantes." France.
@misc{etde_20873620,
title = {Experimental studies of ions and atoms interaction with insulating surface; Etude experimentale de l'interaction rasante d'atomes et d'ions sur des surfaces isolantes}
author = {Villette, J}
abstractNote = {Grazing collisions (<3 deg.) of keV ions and atoms: H{sup +}, Ne{sup +}, Ne{sup 0}, Na{sup +} on LiF (001) single crystal, an ionic insulator, are investigated by a time of flight technique. The incident beam is chopped and the scattered particles are collected on a position sensitive detector providing differential cross section while the time of flight gives the energy loss. Deflection plates allow the charge state analysis. Secondary electrons are detected in coincidence allowing direct measurements of electron emission yield, angular and energetic distribution through time of flight measurements. The target electronic structure characterized by a large band gap, governs the collisional processes: charge exchange, electronic excitations and electron emission. In particular, these studies show that the population of local target excitations surface excitons is the major contribution to the kinetic energy transfer (stopping power). Auger neutralization of Ne{sup +} and He{sup +} ions reveals the population of quasi-molecular excitons, an exciton bound on two holes. Referenced in the literature as trion. A direct energy balance determines the binding energy associated with these excited states of the surface. Besides these electronic energy loss processes, two nuclear energy loss mechanisms are characterized. These processes imply momentum transfer to individual target atoms during close binary collisions or, if the projectile is charged, to collective mode of optical phonons induced by the projectile coulomb field. The effect of the temperature on the scattering profile, the contribution of topological surface defects to the energy loss profile and to skipping motion on the surface are analyzed in view of classical trajectory simulations. (author)}
place = {France}
year = {2000}
month = {Oct}
}