B. Chimier | University of Bordeaux (France) (original) (raw)
Papers by B. Chimier
Applied Physics Letters, 2015
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Laser-based Micro- and Nanoprocessing IX, 2015
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Damage to VUV, EUV, and X-ray Optics IV; and EUV and X-ray Optics: Synergy between Laboratory and Space III, 2013
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Laser-Induced Damage in Optical Materials: 2010, 2010
We present a coupled study of laser-induced damage and ablation of fused silica in the femtosecon... more We present a coupled study of laser-induced damage and ablation of fused silica in the femtosecond regime. Both thresholds are essentially different and investigations under a wide excursion of pulse duration (< 10 fs to 300 fs) and applied fluence (Fth < F < 10 Fth) provide quantitative knowledge on i) the strength of the so-called "deterministic" character of femtosecond
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Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM) XVI, 2011
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Physics of Plasmas, 2014
ABSTRACT By using a liquid metal as a target one may significantly enhance the yield of hard x-ra... more ABSTRACT By using a liquid metal as a target one may significantly enhance the yield of hard x-rays with a sequence of two intense femtosecond laser pulses. The influence of the time delay between the two pulses is studied experimentally and interpreted with numerical simulations. It was suggested that the first arbitrary weak pulse produces microjets from the target surface, while the second intense pulse provides an efficient electron heating and acceleration along the jet surface. These energetic electrons are the source of x-ray emission while striking the target surface. The microjet formation is explained based on the results given by both optical diagnostics and hydrodynamic modeling by a collision of shocks originated from two distinct zones of laser energy deposition. (C) 2014 AIP Publishing LLC.
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UVX 2012 - 11e Colloque sur les Sources Cohérentes et Incohérentes UV, VUV et X ; Applications et Développements Récents, 2013
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Nonlinear Optics, 2013
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Physics of Plasmas, 2008
Tight focusing of a subpicosecond laser pulse in transparent dielectrics is an efficient way to r... more Tight focusing of a subpicosecond laser pulse in transparent dielectrics is an efficient way to release laser energy and to produce plasma. A micro-explosion results in a submicrometer cavity formation if the deposited laser energy exceeds a threshold. A self-consistent model is developed that describes this process. The energy deposition is described by a full set of Maxwell's equations in
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Physics of Plasmas, 2008
Interaction of a laser beam with a target may generate a high velocity expanding plasma plume, so... more Interaction of a laser beam with a target may generate a high velocity expanding plasma plume, solid debris, and liquid nano- and microparticles. They can be produced from plasma recombination, vapor condensation or by a direct expulsion of the heated liquid phase. Two distinct sizes of particles are observed depending on the temperature achieved in the plasma plume: Micrometer-size fragments
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Physical Review Letters, 2013
We have probed, with time-resolved x-ray absorption near-edge spectroscopy (XANES), a femtosecond... more We have probed, with time-resolved x-ray absorption near-edge spectroscopy (XANES), a femtosecond-laser-heated aluminum foil with fluences up to 1 J/cm2. The spectra reveal a loss of the short-range order in a few picoseconds. This time scale is compared with the electron-ion equilibration time, calculated with a two-temperature model. Hydrodynamic simulations shed light on complex features that affect the foil dynamics, including progressive density change from solid to liquid (∼10 ps). In this density range, quantum molecular dynamics simulations indicate that XANES is a relevant probe of the ionic temperature.
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Physical Review B, 2011
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Physical Review B, 2009
The expansion of a thin metallic layer isochorically heated by a subpicosecond laser pulse is stu... more The expansion of a thin metallic layer isochorically heated by a subpicosecond laser pulse is studied theoretically and numerically. An analytical model that accounts for the liquid-vapor phase transition in expanding flow is developed. Numerical simulations performed for an aluminum target that is described by a multiphase equation of state confirm the analytical model. A repartition of the liquid and
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EPL (Europhysics Letters), 2010
For fast heating, solid-liquid phase transition is generally assumed to be an isochoric process r... more For fast heating, solid-liquid phase transition is generally assumed to be an isochoric process related to the ion temperature. However, the experimental studies of fast melting process do not completely agree with the theory. We discuss the validity of the isochoric assumption for fast heating by considering the fast melting of aluminum and gold thin films. The results show that solid-liquid phase transition can occur due to the foil expansion in a picosecond time scale, without significant ion heating, for deposited energies of the order of the melting enthalpy. The estimated melting time for gold thin film irradiated by a short laser pulse is in agreement with experimental measurements.
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The European Physical Journal Special Topics, 2009
Interaction of a laser beam with a target generates a high velocity expanding plasma plume, solid... more Interaction of a laser beam with a target generates a high velocity expanding plasma plume, solid debris and liquid nano- and microparticles. They are produced from plasma recombination and vapor condensation and can be deposited on optical elements located nearby the target. Two distinct kinds of particles were observed depending on the temperature achieved in the plasma plume: large micrometer-size
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Applied Surface Science, 2012
ABSTRACT Interaction of ultrafast laser, i.e. from the femtosecond (fs) to the nanosecond (ns) re... more ABSTRACT Interaction of ultrafast laser, i.e. from the femtosecond (fs) to the nanosecond (ns) regime, with initially transparent matter may produce very high energy density hot spots in the bulk as well as at the material surface, depending on focusing conditions. In the fs regime, absorption is due to ionisation of the dielectric, which enables absorption process to begin, and then hydrodynamic to take place. In the ns regime both absorption and hydrodynamic are coupled to each other, which complexifies considerably the comprehension but matter structuration looks similar. A numerical tool including solution of 3D Maxwell equations and a rate equation for free electrons is first compared to some available simple models of laser energy absorption. Then, subsequent material deformation, i.e. structuration, is determined by solving hydrodynamic equations, including or not solid behaviour. We show that nature of the final structures strongly depends on the amount of deposited energy and on the shape of the absorption zone. Then we address some problems related to laser-matter structuration of optical and biological materials in the fs, ps and ns regimes.
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Applied Physics Letters, 2015
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Laser-based Micro- and Nanoprocessing IX, 2015
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Damage to VUV, EUV, and X-ray Optics IV; and EUV and X-ray Optics: Synergy between Laboratory and Space III, 2013
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Laser-Induced Damage in Optical Materials: 2010, 2010
We present a coupled study of laser-induced damage and ablation of fused silica in the femtosecon... more We present a coupled study of laser-induced damage and ablation of fused silica in the femtosecond regime. Both thresholds are essentially different and investigations under a wide excursion of pulse duration (< 10 fs to 300 fs) and applied fluence (Fth < F < 10 Fth) provide quantitative knowledge on i) the strength of the so-called "deterministic" character of femtosecond
Bookmarks Related papers MentionsView impact
Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM) XVI, 2011
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Physics of Plasmas, 2014
ABSTRACT By using a liquid metal as a target one may significantly enhance the yield of hard x-ra... more ABSTRACT By using a liquid metal as a target one may significantly enhance the yield of hard x-rays with a sequence of two intense femtosecond laser pulses. The influence of the time delay between the two pulses is studied experimentally and interpreted with numerical simulations. It was suggested that the first arbitrary weak pulse produces microjets from the target surface, while the second intense pulse provides an efficient electron heating and acceleration along the jet surface. These energetic electrons are the source of x-ray emission while striking the target surface. The microjet formation is explained based on the results given by both optical diagnostics and hydrodynamic modeling by a collision of shocks originated from two distinct zones of laser energy deposition. (C) 2014 AIP Publishing LLC.
Bookmarks Related papers MentionsView impact
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UVX 2012 - 11e Colloque sur les Sources Cohérentes et Incohérentes UV, VUV et X ; Applications et Développements Récents, 2013
Bookmarks Related papers MentionsView impact
Nonlinear Optics, 2013
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Physics of Plasmas, 2008
Tight focusing of a subpicosecond laser pulse in transparent dielectrics is an efficient way to r... more Tight focusing of a subpicosecond laser pulse in transparent dielectrics is an efficient way to release laser energy and to produce plasma. A micro-explosion results in a submicrometer cavity formation if the deposited laser energy exceeds a threshold. A self-consistent model is developed that describes this process. The energy deposition is described by a full set of Maxwell's equations in
Bookmarks Related papers MentionsView impact
Physics of Plasmas, 2008
Interaction of a laser beam with a target may generate a high velocity expanding plasma plume, so... more Interaction of a laser beam with a target may generate a high velocity expanding plasma plume, solid debris, and liquid nano- and microparticles. They can be produced from plasma recombination, vapor condensation or by a direct expulsion of the heated liquid phase. Two distinct sizes of particles are observed depending on the temperature achieved in the plasma plume: Micrometer-size fragments
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Physical Review Letters, 2013
We have probed, with time-resolved x-ray absorption near-edge spectroscopy (XANES), a femtosecond... more We have probed, with time-resolved x-ray absorption near-edge spectroscopy (XANES), a femtosecond-laser-heated aluminum foil with fluences up to 1 J/cm2. The spectra reveal a loss of the short-range order in a few picoseconds. This time scale is compared with the electron-ion equilibration time, calculated with a two-temperature model. Hydrodynamic simulations shed light on complex features that affect the foil dynamics, including progressive density change from solid to liquid (∼10 ps). In this density range, quantum molecular dynamics simulations indicate that XANES is a relevant probe of the ionic temperature.
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Physical Review B, 2011
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Physical Review B, 2009
The expansion of a thin metallic layer isochorically heated by a subpicosecond laser pulse is stu... more The expansion of a thin metallic layer isochorically heated by a subpicosecond laser pulse is studied theoretically and numerically. An analytical model that accounts for the liquid-vapor phase transition in expanding flow is developed. Numerical simulations performed for an aluminum target that is described by a multiphase equation of state confirm the analytical model. A repartition of the liquid and
Bookmarks Related papers MentionsView impact
EPL (Europhysics Letters), 2010
For fast heating, solid-liquid phase transition is generally assumed to be an isochoric process r... more For fast heating, solid-liquid phase transition is generally assumed to be an isochoric process related to the ion temperature. However, the experimental studies of fast melting process do not completely agree with the theory. We discuss the validity of the isochoric assumption for fast heating by considering the fast melting of aluminum and gold thin films. The results show that solid-liquid phase transition can occur due to the foil expansion in a picosecond time scale, without significant ion heating, for deposited energies of the order of the melting enthalpy. The estimated melting time for gold thin film irradiated by a short laser pulse is in agreement with experimental measurements.
Bookmarks Related papers MentionsView impact
The European Physical Journal Special Topics, 2009
Interaction of a laser beam with a target generates a high velocity expanding plasma plume, solid... more Interaction of a laser beam with a target generates a high velocity expanding plasma plume, solid debris and liquid nano- and microparticles. They are produced from plasma recombination and vapor condensation and can be deposited on optical elements located nearby the target. Two distinct kinds of particles were observed depending on the temperature achieved in the plasma plume: large micrometer-size
Bookmarks Related papers MentionsView impact
Applied Surface Science, 2012
ABSTRACT Interaction of ultrafast laser, i.e. from the femtosecond (fs) to the nanosecond (ns) re... more ABSTRACT Interaction of ultrafast laser, i.e. from the femtosecond (fs) to the nanosecond (ns) regime, with initially transparent matter may produce very high energy density hot spots in the bulk as well as at the material surface, depending on focusing conditions. In the fs regime, absorption is due to ionisation of the dielectric, which enables absorption process to begin, and then hydrodynamic to take place. In the ns regime both absorption and hydrodynamic are coupled to each other, which complexifies considerably the comprehension but matter structuration looks similar. A numerical tool including solution of 3D Maxwell equations and a rate equation for free electrons is first compared to some available simple models of laser energy absorption. Then, subsequent material deformation, i.e. structuration, is determined by solving hydrodynamic equations, including or not solid behaviour. We show that nature of the final structures strongly depends on the amount of deposited energy and on the shape of the absorption zone. Then we address some problems related to laser-matter structuration of optical and biological materials in the fs, ps and ns regimes.
Bookmarks Related papers MentionsView impact