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Simulation of femtosecond laser ablation of gold into water. Povarnitsyn M.E. 1 , Itina T.E. 2 , Levashov P.R. 1 , Khishchenko K.V. 1 1 JIHT RAS, Moscow, Russia 2 LabHC, St-Etienne, France povar@ihed.ras.ru.
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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, Russia 2LabHC, St-Etienne, France povar@ihed.ras.ru XXVIII International Conference onInteraction of Intense Energy Fluxes with MatterMarch 2-7, 2013, Elbrus, Kabardino-Balkaria, Russia
Motivation Application of NPs – cancer and antibacterial treatment, imaging, censors, etc. laser H20 Au Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
Size distribution of NPs Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
Problem definition H2O Au = 800 nm, = 200 fs I 1013 W/cm2 laser H20 z Au Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
Two-temperature hydrodynamic model Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
Collision frequency Eidmann et al. PRE 62 (2000) Pump-probe for cold Elsayed et al. PRL 58, 1212 (1987) Cu Groeneveld et al. PRL 64, 784 (1990) Ag Schoenlein et al. PRL 58, 1680 (1987) Au Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
Thermal conductivity and electron-ion coupling Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
Laser energy absorption Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
Phase diagram of Au (EOS) GES library version 1.0.7: #23004 (two-temperature, multi-phase) a – 0 GPa b – -1 GPa c – -4 GPa d – -7 GPa Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
Water Hugoniot curve (EOS) GES library version 1.0.7 #02250 (single-phase, caloric) Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
Model summary • 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 Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
Main stages of fs ablation H2O Au 1) 2) 3) 4) = 800 nm, = 200 fs H2O Te >> Ti Au laser SW H2O SW Au H20 Au H2O Au z Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
I0=2×1013 W/cm2 (Fabs= 0.098 J/cm2) Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
I0=3×1013 W/cm2 (Fabs= 0.26 J/cm2) r 10 – 100 nm Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
I0=4×1013 W/cm2 (Fabs= 0.55 J/cm2) Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
I0=5×1013 W/cm2 (Fabs= 0.95 J/cm2) Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
I0=5×1013 W/cm2 (Fabs= 0.95 J/cm2) Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
Summary • 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 Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…
Publications [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). Povarnitsyn et al. March 2, 2013 Simulation of femtosecond…