C. Laulh, S. Ravy, P. Fertey, E. Elkam, F. LegrandE. Collet, M. Lorenc, M. Buron-Le Cointe, H. CailleauStudies of ultrafast structural changes at SOLEIL synchrotron:

sub-ns and sub-ps pump-probe diffraction on CRISTAL beamline(CRISTAL beamline - SOLEIL synchrotron)(Institute of Physics - Rennes)Ph. Hollander, S. Hustache, J.-P. Ricaud, P. Fret, T. Moreno(SOLEIL synchrotron)M.-L. Boillot(Institut de Chimie Molculaire et Matriaux dOrsay)ANR ULTiMATE ULTrafast co-operative and coherent photo-switching of molecular MATErials

OutlineStudies of ultrafast structural changes at SOLEIL synchrotron:

sub-ns and sub-ps pump-probe diffraction on CRISTAL beamlinePump-probe diffraction: how ?

Pump-probe diffraction: motivations

Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6

Summary

OutlineStudies of ultrafast structural changes at SOLEIL synchrotron:

sub-ns and sub-ps pump-probe diffraction on CRISTAL beamlinePump-probe diffraction: how ?

Pump-probe diffraction: motivations

Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6

Summary

Pump-probe diffraction

Natural temporal width of a synchrotron X-ray pulse: 70 ps FWHM

low- mode: 10 ps FWHM (preliminary tests in Dec 2011)

Slicing mode: 80 fs FWHM (2014)Making a movie of structural evolutions on the timescales of atomic vibration

E ~ 10 meV Tosc ~ 400 fs Following photoinduced structural changes as a function of timeUndulator80 fs // 70 psLaserh = 1.55 eVt25 fsRX Toward ultrashort X-ray pulses at SOLEIL synchrotron

0 m31.25 m36.00 mCRISTAL: future installation for pump-probe experiments6-circle4-circleUndulator

0 m31.25 m36.00 mCRISTAL: future installation for pump-probe experiments6-circle4-circle42.13 mTi:Sa oscillator + regenerative Ti:Sa amplifier = 800 nm, 25 fs FWHM 500 J/pulse @ 10 kHz, 6 mJ/pulse @ 1 kHz~ 1 ms(~ 1 kHz)Undulator

0 m31.25 m36.00 mCRISTAL: future installation for pump-probe experiments6-circle4-circle42.13 mTi:Sa oscillator + regenerative Ti:Sa amplifier = 800 nm, 25 fs FWHM 500 J/pulse @ 10 kHz, 6 mJ/pulse @ 1 kHz~ 1 ms(~ 1 kHz)UndulatorXPAD detector Photon counting enabled on level high of a logic gate Up to 847 kHz frequency90 nsDelayDelay [ns]Total intensity [a.u.]x 106

OutlineStudies of ultrafast structural changes at SOLEIL synchrotron:

sub-ns and sub-ps pump-probe diffraction on CRISTAL beamlinePump-probe diffraction: how ?

Pump-probe diffraction: motivations

Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6

Summary

Laser-induced phenomena in condensed mattert : few fs Out-of-equilibrium states Decoupled degrees of freedom t = 0 : laser driven electronic transition = 800 nm E = 1.55 eV

t < few ps : coherent phononsLaser-induced phenomena in condensed mattert : few fs Out-of-equilibrium states Decoupled degrees of freedom t = 0 : laser driven electronic transition = 800 nm E = 1.55 eVLa0.42Ca0.58MnO3P. Beaud et al.,PRL (2009)Sudden shift of the equilibrium coordinates of the ions:

Displacive excitation(5 3/2 2)Coherent phonons

t < few ps : coherent phononsLaser-induced phenomena in condensed mattert : few fs Out-of-equilibrium states Decoupled degrees of freedom t = 0 : laser driven electronic transition = 800 nm E = 1.55 eVLa0.42Ca0.58MnO3P. Beaud et al.,PRL (2009)Sudden shift of the equilibrium coordinates of the ions:

Displacive excitation(5 3/2 2)Coherent phononst < few 100 ps : ultrafast phase transitionsP. Baum et al., Science (2007)VO2Photoinduced ph. tr.T TcT Tct0t1t2TemperatureLaser excitationt0t1t2

t < few ps : coherent phononsLaser-induced phenomena in condensed mattert : few fs Out-of-equilibrium states Decoupled degrees of freedom t = 0 : laser driven electronic transition = 800 nm E = 1.55 eVLa0.42Ca0.58MnO3P. Beaud et al.,PRL (2009)Sudden shift of the equilibrium coordinates of the ions:

Displacive excitation(5 3/2 2)Coherent phononst < few 100 ps : ultrafast phase transitionsP. Baum et al., Science (2007)VO2Photoinduced ph. tr.T TcT Tct0t1t2TemperatureLaser excitationt0t1t2t in range [10 fs - 100 ps]:

lattice dynamics driven by interactions with electronic degrees of freedom

Laser-induced phenomena in condensed mattert : few fs Out-of-equilibrium states Decoupled degrees of freedom t = 0 : laser driven electronic transition = 800 nm E = 1.55 eVCoherent phononsPhotoinduced ph. tr.t ~ 1 - 100 ns : propagation of deformation wavesPhonon creation: local increase of temperatureStressed regions: propagation of a strain wavecompressive strainStrain wavesHeat diff.t ~ 1 - 10 s : laser-induced heat diffusionHeat diffusion: homogeneisation of temperature

Laser-induced phenomena in condensed mattert : few fs Out-of-equilibrium states Decoupled degrees of freedom t = 0 : laser driven electronic transition = 800 nm E = 1.55 eVCoherent phononsPhotoinduced ph. tr.t ~ 1 - 100 ns : propagation of deformation wavesPhonon creation: local increase of temperatureStressed regions: propagation of a strain wavecompressive strainStrain wavesHeat diff.t ~ 1 - 10 s : laser-induced heat diffusionHeat diffusion: homogeneisation of temperaturet in range [100 ps - 10 s]:

Laser induced strain waves and heat diffusion - control of the electronic properties ??

OutlineStudies of ultrafast structural changes at SOLEIL synchrotron:

sub-ns and sub-ps pump-probe diffraction on CRISTAL beamlinePump-probe diffraction: how ?

Pump-probe diffraction: motivations

Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6

Summary

Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6[TPA (FeIII) TCC]Tris(2-pyridylmthyle)3,4,5,6-tetrachlorocatecholateLattice cooperative effects?[TPA (FeIII) TCC] PF6

Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6[TPA (FeIII) TCC]Tris(2-pyridylmthyle)3,4,5,6-tetrachlorocatecholateLattice cooperative effects?[TPA (FeIII) TCC] PF6M. Lorenc et al., PRL 103 028301 (2009) Time-resolved structure determination at 180 K: :fraction of moleculesin the HS stateUnit cell parameter a :elastic deformationsDebye-Waller factor B:crystal temperature

Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6[TPA (FeIII) TCC]Tris(2-pyridylmthyle)3,4,5,6-tetrachlorocatecholateLattice cooperative effects?[TPA (FeIII) TCC] PF6M. Lorenc et al., PRL 103 028301 (2009) Time-resolved structure determination at 180 K: :fraction of moleculesin the HS stateUnit cell parameter a :elastic deformationsDebye-Waller factor B:crystal temperature1

Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6[TPA (FeIII) TCC]Tris(2-pyridylmthyle)3,4,5,6-tetrachlorocatecholateLattice cooperative effects?[TPA (FeIII) TCC] PF6M. Lorenc et al., PRL 103 028301 (2009) Time-resolved structure determination at 180 K: :fraction of moleculesin the HS stateUnit cell parameter a :elastic deformationsDebye-Waller factor B:crystal temperature12

Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6[TPA (FeIII) TCC]Tris(2-pyridylmthyle)3,4,5,6-tetrachlorocatecholateLattice cooperative effects?[TPA (FeIII) TCC] PF6M. Lorenc et al., PRL 103 028301 (2009) Time-resolved structure determination at 180 K: :fraction of moleculesin the HS stateUnit cell parameter a :elastic deformationsDebye-Waller factor B:crystal temperature123

Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6[TPA (FeIII) TCC]Tris(2-pyridylmthyle)3,4,5,6-tetrachlorocatecholateLattice cooperative effects?[TPA (FeIII) TCC] PF6M. Lorenc et al., PRL 103 028301 (2009) Time-resolved structure determination at 180 K: :fraction of moleculesin the HS stateUnit cell parameter a :elastic deformationsDebye-Waller factor B:crystal temperature1234

Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6 Experimental setup

Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6 Experimental setup Rocking curve measurementsEwald spherekphi-scan Imaging the 002 Bragg spot in 3DBragg spot extensions along a and b:

Spread of (002) lattice plane tiltingsin the a and b directionsacb

Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6

Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6

Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6Two characteristic timescales:- Few 100 ns after excitation: peak broadening without profile change - Few s after excitation: peak broadening with apparition of a tail

Two lattice plane deformation cycles:- During step 2) propagation of deformation waves- During step 3) heat diffusion

Summary First time-resolved experiment at the CRISTAL beamline [ns resolution]

[TPA Fe(III) TCC] PF6: lattice plane deformations in laser-induced transient states

Improvement of the temporal resolution:- November 2011: reception of a fs laser 70 ps resolution

- Year 2012: optimization of the low-alpha mode of operation 10 ps resolution

- Year 2014: slicing mode of operation 100 fs resolution Study of the interplays between lattice and electronic degrees of freedom

Control of electronic properties in molecular crystals

undulatorlaserwigglerbendingmagnet e-beam 70ps75fs75fsSub-ps resolution: slicing Time resolution ~ 100 fswigglerelectron bunch(70 ps)Laser pulse: 25 fs, few mJ2.5 kHz, 800 nmExchange of energybetween electrons and IR photonsbendingmagnetIn the sliced zone, the electrons have energies spanning the range [E-E ; E+ E]. They will be spatially dispersed during their pass in the bending magnet.electron bunch(75 fs)Seminal paper :Zholents and Zolotorev, PRL 76 912 (1996)

Available at Bessy, SLS, ALSLaser

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