Dynamics of irradiated clusters and molecules

1. Solvated molecules Free clusters Laser Projectile Electron Emission Deposited clusters • Irradiation of solvated • « bio »molecules • Microscopic mechanisms • - Role of water environment • Medical applications • Society applications Dynamics of irradiatedclusters and molecules • Laser irradiations of • free clusters • Huge energy absorption in • intense laser fields • Production of energetic • electrons, ions, photons • - Many-body « laboratory » • Time resolved dynamics Deposited/embedded species - Shaping at nanoscale - Defect formation - Chromophore effects and therapy applications

2. Implies: • Variety of systems • Variety of time scales • Variety of scenarios • Implies: • Robustness • Flexibility • Modularity • Implies: • Use of well tested methods • Simplicity • Documentation Specifications Dynamical description of irradiation and response of -Electrons -Ions -Environment

3. Example: Na+9 + laser E Laser polarization Laser intensity  0 I = 5. 1011 W.cm-2 Pulse in cos2 Delay = 50 fs FWHM = 125 fs w = 2.3 eV

4. Time DependentDensity Functional Theory (TDDFT) Ensemble of orbitals (1 electron) / no correlation One body density Effective mean field theory (Kohn-Sham) Kohn-Sham potential Ions + ext. Coulomb direct Exch. + Corr. TDLDA-MD : coupled non adiabatic electrons + ions dynamics Model (cluster/molecule)  Electrons Local Density Approximation (LDA) +Self Interaction Correction (SIC) … Semi-classical theory available (Vlasov, VUU) Ions Explicit ions via pseudo potentials Detail of structure + ionic Molecular Dynamics (MD)

5. Time DependentDensity Functional Theory (TDDFT) Ensemble of orbitals (1 electron) / no correlation One body density Effective mean field theory (Kohn-Sham) Kohn-Sham potential Ions + ext. Coulomb direct Exch. + Corr. TDLDA-MD : coupled non adiabatic electrons + ions dynamics Model (cluster/molecule)  Electrons fs ps Local Density Approximation (LDA) +Self Interaction Correction (SIC) … Semi-classical theory available (Vlasov, VUU) Ions Explicit ions via pseudo potentials Detail of structure + ionic Molecular Dynamics (MD)

6. Optical response : Dipole Spectral analysis Photoabsorption cross sections Ionization Total number of emitted electrons Ionization probabilities Kinetic energy spectra of electrons (PES) Angular distributions of emitted electrons (PAD) Positions and velocities Kinetic energy, temperature Observables  Electrons  Excitation energy Ions

7. Photoelectrons Yield Ionization Yield Electron energy Laser (w, I, t, z) Photon energy Electron emission from irradiated clusters ds/dE s ( w )

8. I Photoelectrons Yield Ionization Yield Time resolved dynamics Electron energy III Yield Optical Response Laser (w, I, t, z) Angular distrib. II Yield FEL lasers Angle Energy resol. angul. distri. Electron emission from irradiated clusters Electron emission from irradiated clusters ds/dE ds/dW Photon energy Laser s ( w )

9. I Photoelectrons Yield Ionization Yield Electron energy Yield Optical Response Laser (w, I, t, z) Angular distrib. Yield Angle Electron emission from irradiated clusters Electron emission from irradiated clusters ds/dE Time resolved dynamics ds/dW III II Photon energy FEL lasers Laser s ( w ) Energy resol. angul. distri.

10. Theo PAD Exp C60 Angle Exp Theo Exp Freiburg Exp. Rostock Laser polarization Level energy Energy resolved angular distributions Angle-energy correlation ds/dWdE

11. Theo Na58 (no 2d) Jellium Orientation Average PAD Exp C60 Angle Exp Theo Exp Freiburg Exp. Rostock Laser polarization Level energy Energy resolved angular distributions The orientation Problem… Angle-energy correlation ds/dWdE

12. I Photoelectrons Yield Ionization Yield Electron energy Yield Optical Response Laser (w, I, t, z) Angular distrib. Yield Angle Electron emission from irradiated clusters Electron emission from irradiated clusters ds/dE Time resolved dynamics ds/dW III II Photon energy FEL lasers Laser s ( w ) Energy resol. angul. distri.

13. C2H4 Organic molecule as test case for irradiation with very high frequency lasers Comparison to metal clusters (resonance) Laser polariz. Below resonances Resonance region Well above reson. FWHM = 20 fs Ethylene in laser fields

14. I Photoelectrons Yield Ionization Yield Electron energy Yield Optical Response Laser (w, I, t, z) Angular distrib. Yield Angle Electron emission from irradiated clusters Electron emission from irradiated clusters ds/dE Time resolved dynamics ds/dW III II Photon energy FEL lasers Laser s ( w ) Energy resol. angul. distri.

15. I Photoelectrons Yield Ionization Yield Electron energy w w Yield Optical Response Laser (w, I, t, z) Angular distrib. Yield Angle Electron emission from irradiated clusters Electron emission from irradiated clusters ds/dE Time resolved dynamics ds/dW III II Photon energy FEL lasers Laser s ( w ) Energy resol. angul. distri.

16. I Photoelectrons Yield Ionization Yield Electron energy w Yield Optical Response Laser (w, I, t, z) Angular distrib. II Yield FEL lasers Angle Electron emission from irradiated clusters Electron emission from irradiated clusters ds/dE Time resolved dynamics ds/dW III Photon energy Laser s ( w ) Energy resol. angul. distri.

17. I Photoelectrons Yield Ionization Yield Electron energy w Laser (w, I, t, z) Angular distrib. II Yield FEL lasers Angle Electron emission from irradiated clusters Electron emission from irradiated clusters ds/dE Time resolved dynamics Yield Optical Response ds/dW III Photon energy Laser s ( w ) Energy resol. angul. distri.

18. I Photoelectrons Yield Ionization Yield Electron energy w Laser (w, I, t, z) Angular distrib. II Yield FEL lasers Angle Electron emission from irradiated clusters Electron emission from irradiated clusters ds/dE Time resolved dynamics Yield Optical Response ds/dW III Photon energy Laser s ( w ) Energy resol. angul. distri.

19. Probe Ionization Pump Ionization Weak w2Mie ~ 1 / R3 / Ioniz. Mie Plasmon Time / Delay Pump – probe for vibration Strong Ionization maps Vibrations

20. Probe Pump Structure (vibrations…) Dynamics (viscosity…) Exp. Gerber Monopole « Pump – Probe »Dynamics Ionization as a function of delay between pump and probe laser pulses Ionic vibration period Expansion rate

21. Laser Projectile • Environment • Hierarchical model • Dynamical QM/MM • - Na@Ar, Kr, Ne done • - Na @ MgO done • - Na@H2O in the oven • - C, N, O @ H2O in near future • - C, N, O @ H2O @Ar in future Solvated molecules Irradiation of clusters and molecules • Time resolved dynamics • Key importance of non adiabatic • electron/ion couplings • Photoelectron spectroscopy • energy, angle done/ in the oven • - Pump and probe scenarios done • FEL laser domain in the oven • Collisional scenarios in near future • Atto laser domain in the oven Dynamical description of irradiation and response of - electrons - ions - environment Free clusters Dynamics of ionization in TDDFT - Self Interaction problem (SIC) - Benchmark TDSIC calculationdone - Simple approximationsin the oven - Dynamical correlationsin the future (electronic transport) Signals from electrons People P. M. Dinh, P. G. Reinhard, ES, Z. Wang Electron Emission Deposited clusters

22. Example of collision : Na+9 + Ar 8+ E = 2.32 keV b = 20 a0