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Title: Dielectric properties of laser exploded clusters

Abstract

The optical properties of a gas of laser-pulse exploded clusters are determined by the time evolving polarizabilities of individual clusters. In turn, the polarizability of an individual cluster is determined by the time evolution of individual electrons within the cluster's electrostatic potential. We calculate the linear cluster polarizability using the Vlasov equation. A quasistatic equilibrium is calculated from a bi-Maxwellian distribution that models both the hot and cold electrons, using inputs from a particle-in-cell simulation [T. Taguchi et al., Phys. Rev. Lett. 92, 205003 (2004)]. We then perturb the system to first order in the field and integrate the response of individual electrons to the self-consistent field following unperturbed orbits. The dipole spectrum depicts strong absorption at frequencies much smaller than {omega}{sub p}/{radical}2. This enhanced absorption results from a beating of the laser field with electron orbital motion.

Authors:
; ;  [1]
  1. Institute for Research in Electrical and Applied Physics, University of Maryland, College Park, Maryland 20742 (United States)
Publication Date:
OSTI Identifier:
20974890
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 3; Other Information: DOI: 10.1063/1.2712814; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ABSORPTION; ATOMIC CLUSTERS; BOLTZMANN-VLASOV EQUATION; DIELECTRIC PROPERTIES; DIPOLES; ELECTRONS; LASER RADIATION; LASERS; OPTICAL PROPERTIES; PLASMA; PLASMA HEATING; PLASMA SIMULATION; POLARIZABILITY; SELF-CONSISTENT FIELD

Citation Formats

Palastro, John P., Antonsen, Thomas, and Gupta, Ayush. Dielectric properties of laser exploded clusters. United States: N. p., 2007. Web. doi:10.1063/1.2712814.
Palastro, John P., Antonsen, Thomas, & Gupta, Ayush. Dielectric properties of laser exploded clusters. United States. doi:10.1063/1.2712814.
Palastro, John P., Antonsen, Thomas, and Gupta, Ayush. Thu . "Dielectric properties of laser exploded clusters". United States. doi:10.1063/1.2712814.
@article{osti_20974890,
title = {Dielectric properties of laser exploded clusters},
author = {Palastro, John P. and Antonsen, Thomas and Gupta, Ayush},
abstractNote = {The optical properties of a gas of laser-pulse exploded clusters are determined by the time evolving polarizabilities of individual clusters. In turn, the polarizability of an individual cluster is determined by the time evolution of individual electrons within the cluster's electrostatic potential. We calculate the linear cluster polarizability using the Vlasov equation. A quasistatic equilibrium is calculated from a bi-Maxwellian distribution that models both the hot and cold electrons, using inputs from a particle-in-cell simulation [T. Taguchi et al., Phys. Rev. Lett. 92, 205003 (2004)]. We then perturb the system to first order in the field and integrate the response of individual electrons to the self-consistent field following unperturbed orbits. The dipole spectrum depicts strong absorption at frequencies much smaller than {omega}{sub p}/{radical}2. This enhanced absorption results from a beating of the laser field with electron orbital motion.},
doi = {10.1063/1.2712814},
journal = {Physics of Plasmas},
number = 3,
volume = 14,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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