c. laulhé, s. ravy, p. fertey, e. elkaïm, f. legrand e. collet, m. lorenc, m. buron-le cointe, h....
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C. Laulhé, S. Ravy, P. Fertey, E. Elkaïm, F. Legrand
E. Collet, M. Lorenc, M. Buron-Le Cointe, H. Cailleau
Studies 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. Féret, T. Moreno(SOLEIL synchrotron)
M.-L. Boillot(Institut de Chimie Moléculaire et Matériaux d’Orsay)
ANR ULTiMATE – « ULTrafast co-operative and coherent photo-switching of molecular MATErials »
Outline
Studies of ultrafast structural changes at SOLEIL synchrotron:
sub-ns and sub-ps pump-probe diffraction on CRISTAL beamline
I. Pump-probe diffraction: how ?
II. Pump-probe diffraction: motivations
III. Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6
IV. Summary
Outline
Studies of ultrafast structural changes at SOLEIL synchrotron:
sub-ns and sub-ps pump-probe diffraction on CRISTAL beamline
I. Pump-probe diffraction: how ?
II. Pump-probe diffraction: motivations
III. Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6
IV. 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 time
Undulator
80 fs // 70 ps
Laserh = 1.55 eV
Δt
25 fs
RX
• Toward ultrashort X-ray pulses at SOLEIL synchrotron…
Onduleur147.6 ns(6.8 MHz)
70 ps
Onduleur147.6 ns(6.8 MHz)
70 ps
0 m31.25 m36.00 m
CRISTAL: future installation for pump-probe experiments
6-circle 4-circle
Undulator
Onduleur147.6 ns(6.8 MHz)
70 ps
Onduleur147.6 ns(6.8 MHz)
70 ps
0 m31.25 m36.00 m
CRISTAL: future installation for pump-probe experiments
6-circle 4-circle
42.13 m
Ti:Sa oscillator + regenerative Ti:Sa amplifier • = 800 nm, 25 fs FWHM• 500 µJ/pulse @ 10 kHz, 6 mJ/pulse @ 1 kHz
~ 1 ms(~ 1 kHz)
Undulator
Onduleur147.6 ns(6.8 MHz)
70 ps
Onduleur147.6 ns(6.8 MHz)
70 ps
0 m31.25 m36.00 m
CRISTAL: future installation for pump-probe experiments
6-circle 4-circle
42.13 m
Ti:Sa oscillator + regenerative Ti:Sa amplifier • = 800 nm, 25 fs FWHM• 500 µJ/pulse @ 10 kHz, 6 mJ/pulse @ 1 kHz
~ 1 ms(~ 1 kHz)
Undulator
XPAD detector• Photon counting enabled on level high of a logic gate• Up to 847 kHz frequency
90 ns
Delay
0 50 100 150 200 2500.0
0.5
1.0
1.51.5
2.0
2.5
Delay [ns]Tota
l in
tensi
ty
[a.u
.]
x 106
Outline
Studies of ultrafast structural changes at SOLEIL synchrotron:
sub-ns and sub-ps pump-probe diffraction on CRISTAL beamline
I. Pump-probe diffraction: how ?
II. Pump-probe diffraction: motivations
III. Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6
IV. Summary
Laser-induced phenomena in condensed matter
t : few fs
→ Out-of-equilibrium states→ Decoupled degrees of freedom
cond.
valence
E
cond.
valence
E
• t = 0 : laser driven electronic transition = 800 nm ↔ E = 1.55 eV
t < few ps : coherent phonons
µsnspsfs10 100 10 100 1010010
Laser-induced phenomena in condensed matter
t : few fs
→ Out-of-equilibrium states→ Decoupled degrees of freedom
cond.
valence
E
cond.
valence
E
• t = 0 : laser driven electronic transition = 800 nm ↔ E = 1.55 eV
Diff
ract
ed
in
ten
sity
(a.u
.)
-0.5 0.0 0.5 1.0 1.5Time (ps)
La0.42Ca0.58MnO3
P. 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 phonons
µsnspsfs10 100 10 100 1010010
Laser-induced phenomena in condensed matter
t : few fs
→ Out-of-equilibrium states→ Decoupled degrees of freedom
cond.
valence
E
cond.
valence
E
• t = 0 : laser driven electronic transition = 800 nm ↔ E = 1.55 eV
Diff
ract
ed
in
ten
sity
(a.u
.)
-0.5 0.0 0.5 1.0 1.5Time (ps)
La0.42Ca0.58MnO3
P. Beaud et al.,PRL (2009)
Sudden shift of the equilibrium coordinates of
the ions:
Displacive excitation
(5 3/2 2)
Coherent phonons
t < few 100 ps : ultrafast phase transitions
P. Baum et al., Science (2007)
VO2
Photoinduced ph. tr.
Diff
ract
ed in
tens
ity (
a.u.
)D
iffra
cted
inte
nsity
(a.
u.)
Diff
ract
ed in
tens
ity (
a.u.
)
T ˂ Tc T ˃ Tc
t0 t1 t2
TemperatureLaser excitation
t0
t1
t2
t < few ps : coherent phonons
µsnspsfs10 100 10 100 1010010
Laser-induced phenomena in condensed matter
t : few fs
→ Out-of-equilibrium states→ Decoupled degrees of freedom
cond.
valence
E
cond.
valence
E
• t = 0 : laser driven electronic transition = 800 nm ↔ E = 1.55 eV
Diff
ract
ed
in
ten
sity
(a.u
.)
-0.5 0.0 0.5 1.0 1.5Time (ps)
La0.42Ca0.58MnO3
P. Beaud et al.,PRL (2009)
Sudden shift of the equilibrium coordinates of
the ions:
Displacive excitation
(5 3/2 2)
Coherent phonons
t < few 100 ps : ultrafast phase transitions
P. Baum et al., Science (2007)
VO2
Photoinduced ph. tr.
Diff
ract
ed in
tens
ity (
a.u.
)D
iffra
cted
inte
nsity
(a.
u.)
Diff
ract
ed in
tens
ity (
a.u.
)
T ˂ Tc T ˃ Tc
t0 t1 t2
TemperatureLaser excitation
t0
t1
t2
t in range [10 fs - 100 ps]:
lattice dynamics driven by interactions with electronic degrees of freedom
µsnspsfs10 100 10 100 1010010
Laser-induced phenomena in condensed matter
t : few fs
→ Out-of-equilibrium states→ Decoupled degrees of freedom
cond.
valence
E
cond.
valence
E
• t = 0 : laser driven electronic transition = 800 nm ↔ E = 1.55 eV
Coherent phonons Photoinduced ph. tr.
t ~ 1 - 100 ns : propagation of deformation waves
Phonon creation: local increase of temperature
Stressed regions: propagation of a strain wave
cond.
valence
E Phonon creation
cond.
valence
E Phonon creation
compressive strain
Strain waves Heat diff.
t ~ 1 - 10 µs : laser-induced heat diffusion
Heat diffusion: homogeneisation of temperature
µsnspsfs10 100 10 100 1010010
Laser-induced phenomena in condensed matter
t : few fs
→ Out-of-equilibrium states→ Decoupled degrees of freedom
cond.
valence
E
cond.
valence
E
• t = 0 : laser driven electronic transition = 800 nm ↔ E = 1.55 eV
Coherent phonons Photoinduced ph. tr.
t ~ 1 - 100 ns : propagation of deformation waves
Phonon creation: local increase of temperature
Stressed regions: propagation of a strain wave
cond.
valence
E Phonon creation
cond.
valence
E Phonon creation
compressive strain
Strain waves Heat diff.
t ~ 1 - 10 µs : laser-induced heat diffusion
Heat diffusion: homogeneisation of temperature
t in range [100 ps - 10 µs]:
Laser induced strain waves and heat diffusion - control of the electronic properties ??
Outline
Studies of ultrafast structural changes at SOLEIL synchrotron:
sub-ns and sub-ps pump-probe diffraction on CRISTAL beamline
I. Pump-probe diffraction: how ?
II. Pump-probe diffraction: motivations
III. Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6
IV. Summary
Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6
[TPA (FeIII) TCC]Tris(2-pyridylméthyle)3,4,5,6-tetrachlorocatecholate
Lattice ↔ cooperative effects?
↑↓ ↑↓ ↑
↑ ↑ ↑↑↑
ETransfert de charge
ligand-métal
h
ΔtΔt = 0 ~ 1 ps1.
55 e
V
10 m
eV
↑↓ ↑↓ ↑
↑ ↑ ↑↑↑
ETransfert de charge
ligand-métal
h
ΔtΔt = 0 ~ 1 ps1.
55 e
V
10 m
eV
[TPA (FeIII) TCC] PF6
Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6
[TPA (FeIII) TCC]Tris(2-pyridylméthyle)3,4,5,6-tetrachlorocatecholate
Lattice ↔ cooperative effects?
↑↓ ↑↓ ↑
↑ ↑ ↑↑↑
ETransfert de charge
ligand-métal
h
ΔtΔt = 0 ~ 1 ps1.
55 e
V
10 m
eV
↑↓ ↑↓ ↑
↑ ↑ ↑↑↑
ETransfert de charge
ligand-métal
h
ΔtΔt = 0 ~ 1 ps1.
55 e
V
10 m
eV
[TPA (FeIII) TCC] PF6
M. Lorenc et al., PRL 103 028301 (2009)
• Time-resolved structure determination at 180 K:
<Fe-N> :fraction of molecules
in the HS state
Unit cell parameter a :elastic deformations
Debye-Waller factor B:crystal temperature
Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6
[TPA (FeIII) TCC]Tris(2-pyridylméthyle)3,4,5,6-tetrachlorocatecholate
Lattice ↔ cooperative effects?
↑↓ ↑↓ ↑
↑ ↑ ↑↑↑
ETransfert de charge
ligand-métal
h
ΔtΔt = 0 ~ 1 ps1.
55 e
V
10 m
eV
↑↓ ↑↓ ↑
↑ ↑ ↑↑↑
ETransfert de charge
ligand-métal
h
ΔtΔt = 0 ~ 1 ps1.
55 e
V
10 m
eV
[TPA (FeIII) TCC] PF6
M. Lorenc et al., PRL 103 028301 (2009)
• Time-resolved structure determination at 180 K:
<Fe-N> :fraction of molecules
in the HS state
Unit cell parameter a :elastic deformations
Debye-Waller factor B:crystal temperature
1
Photoinduced effects in [TPA Fe(III) TPP] PF6:
1) Laser induced switching of molecules
Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6
[TPA (FeIII) TCC]Tris(2-pyridylméthyle)3,4,5,6-tetrachlorocatecholate
Lattice ↔ cooperative effects?
↑↓ ↑↓ ↑
↑ ↑ ↑↑↑
ETransfert de charge
ligand-métal
h
ΔtΔt = 0 ~ 1 ps1.
55 e
V
10 m
eV
↑↓ ↑↓ ↑
↑ ↑ ↑↑↑
ETransfert de charge
ligand-métal
h
ΔtΔt = 0 ~ 1 ps1.
55 e
V
10 m
eV
[TPA (FeIII) TCC] PF6
M. Lorenc et al., PRL 103 028301 (2009)
• Time-resolved structure determination at 180 K:
<Fe-N> :fraction of molecules
in the HS state
Unit cell parameter a :elastic deformations
Debye-Waller factor B:crystal temperature
1 2
Photoinduced effects in [TPA Fe(III) TPP] PF6:
1) Laser induced switching of molecules
2) Deformation wave propagation
Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6
[TPA (FeIII) TCC]Tris(2-pyridylméthyle)3,4,5,6-tetrachlorocatecholate
Lattice ↔ cooperative effects?
↑↓ ↑↓ ↑
↑ ↑ ↑↑↑
ETransfert de charge
ligand-métal
h
ΔtΔt = 0 ~ 1 ps1.
55 e
V
10 m
eV
↑↓ ↑↓ ↑
↑ ↑ ↑↑↑
ETransfert de charge
ligand-métal
h
ΔtΔt = 0 ~ 1 ps1.
55 e
V
10 m
eV
[TPA (FeIII) TCC] PF6
M. Lorenc et al., PRL 103 028301 (2009)
• Time-resolved structure determination at 180 K:
<Fe-N> :fraction of molecules
in the HS state
Unit cell parameter a :elastic deformations
Debye-Waller factor B:crystal temperature
1 2 3
Photoinduced effects in [TPA Fe(III) TPP] PF6:
1) Laser induced switching of molecules
2) Deformation wave propagation3) Heat diffusion in the crystal
Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6
[TPA (FeIII) TCC]Tris(2-pyridylméthyle)3,4,5,6-tetrachlorocatecholate
Lattice ↔ cooperative effects?
↑↓ ↑↓ ↑
↑ ↑ ↑↑↑
ETransfert de charge
ligand-métal
h
ΔtΔt = 0 ~ 1 ps1.
55 e
V
10 m
eV
↑↓ ↑↓ ↑
↑ ↑ ↑↑↑
ETransfert de charge
ligand-métal
h
ΔtΔt = 0 ~ 1 ps1.
55 e
V
10 m
eV
[TPA (FeIII) TCC] PF6
M. Lorenc et al., PRL 103 028301 (2009)
• Time-resolved structure determination at 180 K:
<Fe-N> :fraction of molecules
in the HS state
Unit cell parameter a :elastic deformations
Debye-Waller factor B:crystal temperature
1 2 3 4
Photoinduced effects in [TPA Fe(III) TPP] PF6:
1) Laser induced switching of molecules
2) Deformation wave propagation3) Heat diffusion in the crystal4) Relaxation
Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6
Nd:YAG laser
Open flow N2 cryostat
XPAD 3.2 X-rays
6-circle diffractometer
Continuum – Minilite I
kphikphi
100 µm
kphi
Sample: [TPA Fe(III) TCC] PF6
Pump and probe beam characteristics
Laser X-rays
Wavelength / energy 1064 nm 18.623 keV
Pulse duration 6 ns 70 ps
Power 100 µJ/pulse/mm²
1.3 105
photon/pulse
Spot characteristics Φ 2 mm Rectangular,135 x 450 µm²
Repetition rate: 10 Hz
• Test experiment on CRISTAL• Experimental setup
Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6
Nd:YAG laser
Open flow N2 cryostat
XPAD 3.2 X-rays
6-circle diffractometer
Continuum – Minilite I
kphikphi
100 µm
kphi
Sample: [TPA Fe(III) TCC] PF6
Pump and probe beam characteristics
Laser X-rays
Wavelength / energy 1064 nm 18.623 keV
Pulse duration 6 ns 70 ps
Power 100 µJ/pulse/mm²
1.3 105
photon/pulse
Spot characteristics Φ 2 mm Rectangular,135 x 450 µm²
Repetition rate: 10 Hz
• Test experiment on CRISTAL• Experimental setup kphi
X-rays
002
ckphi
• Rocking curve measurements
Ewald sphere
kphi-scan ↔ Imaging the 002 Bragg spot in 3D
Bragg spot extensions along a and b:
Spread of (002) lattice plane tiltingsin the a and b directions
a
cb
Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6
0 ns
- 10 µs
50 ns
100 ns
300 ns
700 ns
1 µs
5 µs
10 µs
50 µs
100 µs
500 µs
log
0 ns0 ns
- 10 µs- 10 µs
50 ns50 ns
100 ns100 ns
300 ns300 ns
700 ns700 ns
1 µs1 µs
5 µs5 µs
10 µs10 µs
50 µs50 µs
100 µs100 µs
500 µs500 µs
loglog
a
cb
a
cb ∑
Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6
0 ns
- 10 µs
50 ns
100 ns
300 ns
700 ns
1 µs
5 µs
10 µs
50 µs
100 µs
500 µs
log
0 ns0 ns
- 10 µs- 10 µs
50 ns50 ns
100 ns100 ns
300 ns300 ns
700 ns700 ns
1 µs1 µs
5 µs5 µs
10 µs10 µs
50 µs50 µs
100 µs100 µs
500 µs500 µs
loglog
a
cb
a
cb ∑
a
cb
a
cb∑
Test experiment: photoinduced effects in [TPA Fe(III) TCC] PF6
0 ns
- 10 µs
50 ns
100 ns
300 ns
700 ns
1 µs
5 µs
10 µs
50 µs
100 µs
500 µs
log
0 ns0 ns
- 10 µs- 10 µs
50 ns50 ns
100 ns100 ns
300 ns300 ns
700 ns700 ns
1 µs1 µs
5 µs5 µs
10 µs10 µs
50 µs50 µs
100 µs100 µs
500 µs500 µs
loglog
a
cb
a
cb ∑
a
cb
a
cb∑
Two characteristic timescales:- Few 100 ns after excitation: peak broadening without profile change - Few µs 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
undulator
laser
wiggler
bending
magnet
e-be
am
70ps
75fs
75fs
Sub-ps resolution: slicing
• Time resolution ~ 100 fs
wiggler
electron bunch(70 ps)
Laser pulse: 25 fs, few mJ2.5 kHz, 800 nm
Exchange of energybetween electrons and IR photons
bending
magnet
In the “sliced” zone, the electrons have energies spanning the range [E-ΔE ; E+ ΔE]. 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, ALS
Laser