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Title: Heating model for metals irradiated by a subpicosecond laser pulse

Abstract

We propose a model describing the heating and ablation of a metallic target irradiated by a subpicosecond laser pulse. It takes into account the temperature equilibration between the electrons and ions and the density variation of the target material during the heating process. A simple analytical equation of state is developed, which allows one to calculate the total pressure in the heated layer for different electron and ion temperatures. The thermodynamic behavior of a nonequilibrium system is discussed, and nonequilibrium spinodals and cohesion limits are introduced. The model is applied for a description of the thermal ablation process driven by a sub-ps laser pulse. Aluminum and copper targets are considered, and it is shown that the dominant ablation process is due to breaking the nonequilibrium cohesion limit. The numerical results are in good agreement with recent experimental data.

Authors:
; ;  [1]
  1. Centre Lasers Intenses et Applications, UMR 5107 CNRS, Universite Bordeaux 1, CEA, Universite Bordeaux 1, 351, Cours de la Liberation, 33405 Talence Cedex (France)
Publication Date:
OSTI Identifier:
20951428
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 19; Other Information: DOI: 10.1103/PhysRevB.75.195124; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABLATION; ALUMINIUM; COPPER; DENSITY; ELECTRONS; EQUATIONS OF STATE; HEATING; ION TEMPERATURE; IONS; IRRADIATION; LASER RADIATION; LASERS; PULSES

Citation Formats

Chimier, B., Tikhonchuk, V. T., and Hallo, L.. Heating model for metals irradiated by a subpicosecond laser pulse. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.195124.
Chimier, B., Tikhonchuk, V. T., & Hallo, L.. Heating model for metals irradiated by a subpicosecond laser pulse. United States. doi:10.1103/PHYSREVB.75.195124.
Chimier, B., Tikhonchuk, V. T., and Hallo, L.. Tue . "Heating model for metals irradiated by a subpicosecond laser pulse". United States. doi:10.1103/PHYSREVB.75.195124.
@article{osti_20951428,
title = {Heating model for metals irradiated by a subpicosecond laser pulse},
author = {Chimier, B. and Tikhonchuk, V. T. and Hallo, L.},
abstractNote = {We propose a model describing the heating and ablation of a metallic target irradiated by a subpicosecond laser pulse. It takes into account the temperature equilibration between the electrons and ions and the density variation of the target material during the heating process. A simple analytical equation of state is developed, which allows one to calculate the total pressure in the heated layer for different electron and ion temperatures. The thermodynamic behavior of a nonequilibrium system is discussed, and nonequilibrium spinodals and cohesion limits are introduced. The model is applied for a description of the thermal ablation process driven by a sub-ps laser pulse. Aluminum and copper targets are considered, and it is shown that the dominant ablation process is due to breaking the nonequilibrium cohesion limit. The numerical results are in good agreement with recent experimental data.},
doi = {10.1103/PHYSREVB.75.195124},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 19,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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