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Dynamics of irradiatedclusters and molecules
Solvated molecules
Deposited clusters
Free clusters
ElectronEmission
Laser
Projectile
Irradiation of solvated « bio »molecules- Microscopic mechanisms- Role of water environment- Medical applications- Society applications
Deposited/embedded species- Shaping at nanoscale- Defect formation- Chromophore effects and therapy applications
Laser irradiations of free clusters- Huge energy absorption in intense laser fields- Production of energetic electrons, ions, photons- Many-body « laboratory »- Time resolved dynamics
SpecificationsDynamical descriptionof irradiation and response of - Electrons- Ions - Environment
Implies:
- Variety of systems
- Variety of time scales
- Variety of scenarios
Implies:
- Robustness
- Flexibility
- Modularity
Implies:
- Use of well tested methods
- Simplicity
- Documentation
Example : Na+
9 + laser
I = 5. 1011 W.cm-2 Pulse in cos2
Delay = 50 fsFWHM = 125 fs = 2.3 eV
Laser intensity
0E
Laser polarization
Time Dependent Density Functional Theory (TDDFT)
Ensemble of orbitals (1 electron) / no correlation
One body density
Effective mean field theory (Kohn-Sham)
Explicit ions via pseudo potentials
Detail of structure + ionic Molecular Dynamics (MD)
Ions
Electrons
Kohn-Sham potential Ions + ext.
Local Density Approximation (LDA)
Exch. + Corr. Coulomb direct+ Self Interaction Correction (SIC) …
TDLDA-MD : coupled non adiabatic electrons + ions dynamics
Model (cluster/molecule)
Semi-classical theory available (Vlasov, VUU)
Time Dependent Density Functional Theory (TDDFT)
Ensemble of orbitals (1 electron) / no correlation
One body density
Effective mean field theory (Kohn-Sham)
Explicit ions via pseudo potentials
Detail of structure + ionic Molecular Dynamics (MD)
Ions
Electrons
Kohn-Sham potential Ions + ext.
Local Density Approximation (LDA)
Exch. + Corr. Coulomb direct+ Self Interaction Correction (SIC) …
TDLDA-MD : coupled non adiabatic electrons + ions dynamics
Model (cluster/molecule)
Semi-classical theory available (Vlasov, VUU)
fs
ps
Observables
Optical response : DipoleSpectral analysis Photoabsorption cross sections
Excitation energy
Positions and velocities Kinetic energy, temperature
IonizationTotal number of emitted electronsIonization probabilitiesKinetic energy spectra of electrons (PES)Angular distributions of emitted electrons (PAD)
Ions
Electrons
Electron emission fromirradiated clusters
Las
er (
, I,
, z)
Electron energy
Photoelectrons
Yie
ld( )
d/dE
Ionization
Yie
ld
Photon energy
I
Energy resol. angul. distri.
Electron emission fromirradiated clusters
Las
er (
, I,
, z)
Photoelectrons
Electron energy
Yie
ld
Angle
Angular distrib.
Yie
ld( ) La
ser
Ionization
Yie
ld
d/dE
d/d
Photon energy
Electron emission fromirradiated clusters
III
Time resolved dynamics
FEL lasers
II
Optical Response
Yie
ld
Electron emission fromirradiated clusters
Las
er (
, I,
, z)
Photoelectrons
Electron energy
Yie
ld
Angle
Angular distrib.
Yie
ld( ) La
ser
Ionization
Yie
ld
d/dE
d/d
Photon energy
Electron emission fromirradiated clusters
FEL lasers
I
III
Time resolved dynamics
Energy resol. angul. distri.
II
Optical Response
Yie
ld
Exp F
reiburg
Level energy
Exp
Energy resolved angular distributions
Angle-energy correlation
d/ddE
Laser polarization
Exp
. Ros
tock
Angle C60
Theo
PADExp
Theo
Energy resolved angular distributions
Laser polarization
Exp
. Ros
tock
Angle C60
TheoNa58 (no 2d)JelliumOrientation Average
Angle-energy correlation
d/ddE
The orientation Problem…
Exp F
reiburg
Level energy
Exp
PADExp
Theo
Electron emission fromirradiated clusters
Las
er (
, I,
, z)
Photoelectrons
Electron energy
Yie
ld
Angle
Angular distrib.
Yie
ld( ) La
ser
Ionization
Yie
ld
d/dE
d/d
Photon energy
Electron emission fromirradiated clusters
FEL lasers
I
III
Time resolved dynamics
Energy resol. angul. distri.
II
Optical Response
Yie
ld
FWHM = 20 fs
C2H4
Laser polariz.
Below resonances Resonance region Well above reson.
Ethylene in laser fields
Organic molecule as test case for irradiation with very high frequency lasersComparison to metal clusters (resonance)
Electron emission fromirradiated clusters
Las
er (
, I,
, z)
Photoelectrons
Electron energy
Yie
ld
Angle
Angular distrib.
Yie
ld( ) La
ser
Ionization
Yie
ld
d/dE
d/d
Photon energy
Electron emission fromirradiated clusters
FEL lasers
I
III
Time resolved dynamics
Energy resol. angul. distri.
II
Optical Response
Yie
ld
Electron emission fromirradiated clusters
Las
er (
, I,
, z)
Photoelectrons
Electron energy
Yie
ld
Angle
Angular distrib.
Yie
ld( ) La
ser
Ionization
Yie
ld
d/dE
d/d
Photon energy
Electron emission fromirradiated clusters
FEL lasers
I
III
Time resolved dynamics
Energy resol. angul. distri.
II
Optical Response
Yie
ld
Las
er (
, I,
, z)
FEL lasers
II
Electron emission fromirradiated clusters Photoelectrons
Electron energy
Yie
ld
Angle
Angular distrib.
Yie
ld( ) La
ser
Ionization
Yie
ld
d/dE
d/d
Photon energy
Electron emission fromirradiated clusters
I
III
Time resolved dynamics
Energy resol. angul. distri.
Optical Response
Yie
ld
Las
er (
, I,
, z)
FEL lasers
II
Electron emission fromirradiated clusters Photoelectrons
Electron energy
Yie
ld
Angle
Angular distrib.
Yie
ld( ) La
ser
Ionization
Yie
ld
d/dE
d/d
Photon energy
Electron emission fromirradiated clusters
I
III
Time resolved dynamics
Energy resol. angul. distri.
Optical Response
Yie
ld
Las
er (
, I,
, z)
FEL lasers
II
Electron emission fromirradiated clusters Photoelectrons
Electron energy
Yie
ld
Angle
Angular distrib.
Yie
ld( ) La
ser
Ionization
Yie
ld
d/dE
d/d
Photon energy
Electron emission fromirradiated clusters
I
III
Time resolved dynamics
Energy resol. angul. distri.
Optical Response
Yie
ld
Pump – probe for vibration
Strong
Ionization
Weak
Pump
Probe
Mie ~ / R3
Time / Delay
Pla
smon
Mie
/ Io
niz
.
IonizationmapsVibrations
Ionization
Monopole « Pump – Probe »
Dynamics
Ionization as a function of delay between pump and probe laser pulses
Structure (vibrations…)
Dynamics (viscosity…)
Pu
mp
Pro
be
Ionic vibration period
Expansion rate
Exp. Gerber
Irradiation of clusters and molecules
Laser
Projectile
Signals from electrons
Solvated molecules
Deposited clusters
Free clusters
ElectronEmission
Dynamical descriptionof irradiation and response of - electrons- ions- environment
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
Dynamics of ionization in TDDFT- Self Interaction problem (SIC)- Benchmark TDSIC calculation done- Simple approximations in the oven- Dynamical correlations in the future (electronic transport)
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
PeopleP. M. Dinh, P. G. Reinhard, ES, Z. Wang
Example of collision : Na+
9 + Ar 8+
E = 2.32 keV b = 20 a0
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