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Title: Quantum-size effects in the energy loss of charged particles interacting with a confined two-dimensional electron gas

Abstract

Time-dependent density-functional theory is used to calculate quantum-size effects in the energy loss of antiprotons interacting with a confined two-dimensional electron gas. The antiprotons follow a trajectory normal to jellium circular clusters of variable size, crossing every cluster at its geometrical center. Analysis of the characteristic time scales that define the process is made. For high-enough velocities, the interaction time between the projectile and the target electrons is shorter than the time needed for the density excitation to travel along the cluster. The finite-size object then behaves as an infinite system, and no quantum-size effects appear in the energy loss. For small velocities, the discretization of levels in the cluster plays a role and the energy loss does depend on the system size. A comparison to results obtained using linear theory of screening is made, and the relative contributions of electron-hole pair and plasmon excitations to the total energy loss are analyzed. This comparison also allows us to show the importance of a nonlinear treatment of the screening in the interaction process.

Authors:
 [1];  [2];  [3];  [2]; ;  [4];  [2];  [4];  [2];  [2]
  1. Laboratoire des Collisions Atomiques et Moleculaires (CNRS UMR 8625), Batiment 351, Universite Paris-Sud, 91405 Orsay Cedex (France)
  2. (Spain)
  3. Departamento de Fisica de Materiales, Facultad de Quimicas UPV/EHU, Apartado 1072, 20080 San Sebastian (Spain)
  4. Donostia International Physics Center DIPC, P. Manuel de Lardizabal 4, 20018 San Sebastian (Spain)
Publication Date:
OSTI Identifier:
20786724
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevA.73.012901; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; 36 MATERIALS SCIENCE; ANTIPROTONS; CHARGED PARTICLES; COMPARATIVE EVALUATIONS; DENSITY FUNCTIONAL METHOD; ELECTRON GAS; ELECTRONS; EXCITATION; HOLES; NONLINEAR PROBLEMS; PLASMONS; TIME DEPENDENCE; TWO-DIMENSIONAL CALCULATIONS

Citation Formats

Borisov, A. G., Donostia International Physics Center DIPC, P. Manuel de Lardizabal 4, 20018 San Sebastian, Juaristi, J. I., Unidad de Fisica de Materiales, Centro Mixto CSIC-UPV/EHU, P. Manuel de Lardizabal 3, 20018 San Sebastian, Muino, R. Diez, Sanchez-Portal, D., Unidad de Fisica de Materiales, Centro Mixto CSIC-UPV/EHU, P. Manuel de Lardizabal 3, 20018 San Sebastian, Echenique, P. M., Departamento de Fisica de Materiales, Facultad de Quimicas UPV/EHU, Apartado 1072, 20080 San Sebastian, and Unidad de Fisica de Materiales, Centro Mixto CSIC-UPV/EHU, P. Manuel de Lardizabal 3, 20018 San Sebastian. Quantum-size effects in the energy loss of charged particles interacting with a confined two-dimensional electron gas. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Borisov, A. G., Donostia International Physics Center DIPC, P. Manuel de Lardizabal 4, 20018 San Sebastian, Juaristi, J. I., Unidad de Fisica de Materiales, Centro Mixto CSIC-UPV/EHU, P. Manuel de Lardizabal 3, 20018 San Sebastian, Muino, R. Diez, Sanchez-Portal, D., Unidad de Fisica de Materiales, Centro Mixto CSIC-UPV/EHU, P. Manuel de Lardizabal 3, 20018 San Sebastian, Echenique, P. M., Departamento de Fisica de Materiales, Facultad de Quimicas UPV/EHU, Apartado 1072, 20080 San Sebastian, & Unidad de Fisica de Materiales, Centro Mixto CSIC-UPV/EHU, P. Manuel de Lardizabal 3, 20018 San Sebastian. Quantum-size effects in the energy loss of charged particles interacting with a confined two-dimensional electron gas. United States. doi:10.1103/PHYSREVA.73.0.
Borisov, A. G., Donostia International Physics Center DIPC, P. Manuel de Lardizabal 4, 20018 San Sebastian, Juaristi, J. I., Unidad de Fisica de Materiales, Centro Mixto CSIC-UPV/EHU, P. Manuel de Lardizabal 3, 20018 San Sebastian, Muino, R. Diez, Sanchez-Portal, D., Unidad de Fisica de Materiales, Centro Mixto CSIC-UPV/EHU, P. Manuel de Lardizabal 3, 20018 San Sebastian, Echenique, P. M., Departamento de Fisica de Materiales, Facultad de Quimicas UPV/EHU, Apartado 1072, 20080 San Sebastian, and Unidad de Fisica de Materiales, Centro Mixto CSIC-UPV/EHU, P. Manuel de Lardizabal 3, 20018 San Sebastian. Sun . "Quantum-size effects in the energy loss of charged particles interacting with a confined two-dimensional electron gas". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20786724,
title = {Quantum-size effects in the energy loss of charged particles interacting with a confined two-dimensional electron gas},
author = {Borisov, A. G. and Donostia International Physics Center DIPC, P. Manuel de Lardizabal 4, 20018 San Sebastian and Juaristi, J. I. and Unidad de Fisica de Materiales, Centro Mixto CSIC-UPV/EHU, P. Manuel de Lardizabal 3, 20018 San Sebastian and Muino, R. Diez and Sanchez-Portal, D. and Unidad de Fisica de Materiales, Centro Mixto CSIC-UPV/EHU, P. Manuel de Lardizabal 3, 20018 San Sebastian and Echenique, P. M. and Departamento de Fisica de Materiales, Facultad de Quimicas UPV/EHU, Apartado 1072, 20080 San Sebastian and Unidad de Fisica de Materiales, Centro Mixto CSIC-UPV/EHU, P. Manuel de Lardizabal 3, 20018 San Sebastian},
abstractNote = {Time-dependent density-functional theory is used to calculate quantum-size effects in the energy loss of antiprotons interacting with a confined two-dimensional electron gas. The antiprotons follow a trajectory normal to jellium circular clusters of variable size, crossing every cluster at its geometrical center. Analysis of the characteristic time scales that define the process is made. For high-enough velocities, the interaction time between the projectile and the target electrons is shorter than the time needed for the density excitation to travel along the cluster. The finite-size object then behaves as an infinite system, and no quantum-size effects appear in the energy loss. For small velocities, the discretization of levels in the cluster plays a role and the energy loss does depend on the system size. A comparison to results obtained using linear theory of screening is made, and the relative contributions of electron-hole pair and plasmon excitations to the total energy loss are analyzed. This comparison also allows us to show the importance of a nonlinear treatment of the screening in the interaction process.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 1,
volume = 73,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2006},
month = {Sun Jan 15 00:00:00 EST 2006}
}
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