Simulation of femtosecondlaser ablation of gold into water
Povarnitsyn M.E.1, Itina T.E.2, Levashov P.R.1, Khishchenko K.V.1
1JIHT RAS, Moscow, Russia2LabHC, St-Etienne, France
XXVIII International Conference on Interaction of Intense Energy Fluxes with MatterMarch 2-7, 2013, Elbrus, Kabardino-Balkaria, Russia
Motivation
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
Application of NPs – cancer and antibacterial treatment,imaging, censors, etc.
H20
Au
laser
Size distribution of NPs
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
Problem definition
H20
Au
laser
H2O Au
z
= 800 nm, = 200 fsI 1013 W/cm2
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
Two-temperature hydrodynamic model
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
Eidmann et al. PRE 62 (2000)
Pump-probe for cold
Elsayed et al. PRL 58, 1212 (1987) CuGroeneveld et al. PRL 64, 784 (1990) AgSchoenlein et al. PRL 58, 1680 (1987) Au
Collision frequency
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
Thermal conductivity and electron-ion coupling
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
Laser energy absorption
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
Phase diagram of Au (EOS)
a – 0 GPab – -1 GPac – -4 GPad – -7 GPa
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
GES library version 1.0.7: #23004 (two-temperature, multi-phase)
Water Hugoniot curve (EOS)
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
GES library version 1.0.7 #02250 (single-phase, caloric)
• Two-temperature one-fluid hydrodynamics
• Laser absorption (Helmholtz equation for S or P polarization)
• Electron thermal conductivity
• Electron-ion collisions and energy exchange
• Two-temperature equation of state
• Several materials
Model summary
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
Main stages of fs ablation
H20
Au
laser
H2O Au
z
= 800 nm, = 200 fs
Au
Au
H2O
H2O SW SW
AuH2O
1)
2)
3)
4)
Te >> Ti
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
I0=2×1013 W/cm2 (Fabs= 0.098 J/cm2)
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
I0=3×1013 W/cm2 (Fabs= 0.26 J/cm2)
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
r 10 – 100 nm
I0=4×1013 W/cm2 (Fabs= 0.55 J/cm2)
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
I0=5×1013 W/cm2 (Fabs= 0.95 J/cm2)
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
I0=5×1013 W/cm2 (Fabs= 0.95 J/cm2)
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
• The large-size particles are the result of liquid layer ejection and fragmentation
• The near-critical and supercritical trajectories appear for front target layers and the mass fraction of the liquid–gas mixture increases
• Formation of small NPs can be observed for these trajectories and estimation of the NP size matches quite well with the experimental findings
• The calculation results explain bimodal size distributions of NPs frequently observed in experiment
Summary
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
[1] M.E. Povarnitsyn, N.E. Andreev, E.M. Apfelbaum, T.E. Itina, K.V. Khishchenko, O.F. Kostenko, P.R. Levashov and M.E. Veysman. A wide-range model for simulation of pump-probe experiments with metals. // Applied Surface Science. 258, 9480 (2012).
[2] M. E. Povarnitsyn, N. E. Andreev, P. R. Levashov, K. V. Khishchenko, and O. N. Rosmej. Dynamics of thin metal foils irradiated by moderate-contrast high-intensity laser beams // Phys. Plasmas. 19, 023110 (2012).
[3] M. E. Povarnitsyn, T. E. Itina, P. R. Levashov, K. V. Khishchenko. Mechanisms of nanoparticle formation by ultra-short laser ablation of metals in liquid environment // Phys. Chem. Chem. Phys. 15, 3108 (2013).
Publications
Povarnitsyn et al. Simulation of femtosecond… March 2, 2013
