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 XXVIII International Conference on Interaction of Intense Energy Fluxes with Matter March 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. H20H20 Au laser

Size distribution of NPs Povarnitsyn et al.Simulation of femtosecond…March 2, 2013

Problem definition H20H20 Au laser H2OH2OAu z = 800 nm,  = 200 fs I  W/cm 2 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)Cu Groeneveld et al. PRL 64, 784 (1990)Ag Schoenlein 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 GPa b – -1 GPa c – -4 GPa d – -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 #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 H20H20 Au laser H2OH2OAu z = 800 nm,  = 200 fs Au H2OH2O H2OH2O SW Au H2OH2O 1) 2) 3) 4) T e >> T i Povarnitsyn et al.Simulation of femtosecond…March 2, 2013

I 0 =2×10 13 W/cm 2 (F abs = J/cm 2 ) Povarnitsyn et al.Simulation of femtosecond…March 2, 2013

I 0 =3×10 13 W/cm 2 (F abs = 0.26 J/cm 2 ) Povarnitsyn et al.Simulation of femtosecond…March 2, 2013 r  10 – 100 nm

I 0 =4×10 13 W/cm 2 (F abs = 0.55 J/cm 2 ) Povarnitsyn et al.Simulation of femtosecond…March 2, 2013

I 0 =5×10 13 W/cm 2 (F abs = 0.95 J/cm 2 ) Povarnitsyn et al.Simulation of femtosecond…March 2, 2013

I 0 =5×10 13 W/cm 2 (F abs = 0.95 J/cm 2 )  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, (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

Purpose: Expert system for simulation of laser experiments Principles open user-friendly Tools wide-range physical models simulation module user web interface visualization Benefits experiment cost reduction interpretation of experimental findings education Virtual Laser Laboratory Povarnitsyn et al.Simulation of femtosecond…March 2, 2013 Concept of Virtual Laser Laboratory