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Matter in Extreme Condition atX-ray Free-Electron Lasers
Bob Nagler
Monday, July 2, 12
Collaborators (amongst many others ...)
Orlando Ciricosta, Colin Brown, Andrew Higginbotham, Christopher Murphy, Justin WarkUniversity of Oxford
Byoung-ick Cho, Kyle Engelhorn, Roger Falcone, Phillip HeimannLawrence Berkeley National Laboratory
Bob Nagler, Hae Ja Lee, Eric Galtier, Jacek Krzywinski, Mark Messerschmidt, William Schlotter, Joshua Turner, Catherine Graves, Tianhan Wang, Benny Wu, Diling Zhu, Andreas Scherz, Jerry Hastings, Johannes
SchropSLAC National Accelerator Laboratory
Hyun-Kyung ChungIAEA
Yuan Ping, Damian HirschLawrence Livermore National Laboratory
Tomas Burian, Jaromir Chalupsky, Vera Hajkova, Ludek Vysin, Libor JuhaIOP, Academy of Sciences of the Czech Republic
Sven Toleikis, Marion Harmand, Thomas TschencherDESY
Ulf Zastrau
2
Monday, July 2, 12
Outline
‣ Matter in extreme conditions and high energy density systems
‣ X-ray Free-Electron Lasers are ideal
‣ First experiments
‣ Summary
3
Monday, July 2, 12
Matter in extreme conditions
4Courtesy of Richard W. Lee
Monday, July 2, 12
Matter in extreme conditions occurs widely in nature
5
A.M. Dziewonski and D. L. AndersonPhysics of the Earth and Planetary Interiors 25, 297 (1981).
S. K. Saxena & L. S. Dubrovinsky, American Mineralogist 85, 372 (2000).J. C. Boettger & D. C. Wallace, Physical Review B 55, 2840 (1997).C. S. Yoo et al., Physical Review Letters 70, 3931 (1993).
Monday, July 2, 12
Matter in extreme conditions occurs widely in nature
6
JupiterMetallic H:
200GPa1eV
core H:~5000GPa~10eV
Monday, July 2, 12
Matter in extreme conditions occurs widely in nature
7
Hot Dense Matter (HDM)‣ supernova, stellar interiors, accretion disks‣ plasma devices, laser produced plasmas, Z-
pinches‣ directly and indirectly driven inertial fusion
Warm Dense Matter (WDM)‣ cores of large planets, gas giants‣ transient state in X-ray driven inertial confinement
fusion ‣ systems that start solid and end as a plasma
Monday, July 2, 12
Matter in extreme conditions
8
Matter in Extreme Conditions
‣ High Density‣ High temperature‣ High Pressure, shocks
Monday, July 2, 12
Challenges : numerical code comparison
9
Iron<Z
> a
vera
ge c
harg
e st
ate
Temperature (eV)
8
4
12
16
20 100 200 300
Courtesy of Richard W. Lee
Monday, July 2, 12
Challenges : EOS numerical code comparison
10
Iron Copper
Equation of State: relation between N, P, T
Courtesy of Richard W. Lee
Monday, July 2, 12
11
Monday, July 2, 12
Theoretical Challenges:
12
� =VCoulomb
EKinetic
Monday, July 2, 12
For Solid
‣ V_coulomb (quick estimate):
13
Fc =1
4⇡✏0
q2
r2
Vc ' Fc r
Monday, July 2, 12
For Solid
‣ V_coulomb (quick estimate):
‣ q ~ 1e
‣ r~0.5nm
‣ V_c~5eV
‣ E_thermal ~ kb T ~ 25meV (room temperature)
14
Fc =1
4⇡✏0
q2
r2
� ' 100� 1000
Vc ' Fc r
Monday, July 2, 12
For Plasma
15
Vc ' � 1
4⇡✏0
q2
r
Monday, July 2, 12
For Plasma
‣ V_c = 1-10eV
‣ E_thermal = 1000eV - 10.000eV
16
� ' 10�2 � 10�3
Vc ' � 1
4⇡✏0
q2
r
Monday, July 2, 12
Theoretical challenges: Atomic Physics
17
Debye (screening) Length:
For solid density (~2 10^28 m^-3) and kbT~10eV, we get:
�D ' 1A
Monday, July 2, 12
Challenges : EOS numerical code comparison
18
Iron Copper
Monday, July 2, 12
MEC studies with XUV and X-ray FEL radiation
� < �p � > �p
Optical laser excitation XUV and X-ray laser excitation
� < �p is typically 10-15 eV (UV)
Monday, July 2, 12
Requirements
1. XUV or X-ray wavelength
2. Short pulses, sub-ps)
3. Lots of photons
Monday, July 2, 12
Matter in extreme condition at 4th generation light sources
MEC at LCLS: Matter in Extreme Condition instrument
HEDS instrument at the European X-FEL
Experiments at other Facilities:FLASH: WDM creating Thomson Scattering on Dense He
Experiments at LCLS on existing end-station:SXR: solid density Al Plasma Plasma kinetics in Al PlasmaXPP: Diffraction on Shocked Iron Fourier Domain Interferometry on X-ray heated matterCXI: Diffraction on Shocked Iron
Monday, July 2, 12
Highlight 4 experiments
‣ Creating Transparent Aluminum in Flash
‣ Measuring highly ionized charge states in solid Al at SXR, LCLS
‣ Shock experiments and Equation of State
22
Monday, July 2, 12
Multilayer coated off-axis parabola
FLASH @ 13.5 nm
Target stage scans through focus 4 µm Al filter
Photodiode
Fast shutterApertureGas monitor detector Gas attenuator
Target samples:Al, Mg, Si3N4
3 mm
Monday, July 2, 12
1x1013 1x1014 1x1015 1x1016 1x10170
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Transm
issi
on
Binned
Intensity (W/cm2)1x1013 1x1014 1x1015 1x1016
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Transm
issi
on
Binned
Intensity (W/cm2)
Aluminium Magnesium
Monday, July 2, 12
Saturable absorption in the XUV
1x1013 1x1014 1x1015 1x10160
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Transm
issi
on
Binned
Intensity (W/cm2)
Silicon nitride
Monday, July 2, 12
K-edge
L-edge
ωp
σff
(µm
-1)
Ephot
1s2 2s2 2p6 3s2 3p1 K L M
Electron configuration in atomicaluminium:
1s2
3s2 3p1
2p6
2s2 2p6
Saturable absorption in Aluminium
Monday, July 2, 12
L-edge shift
Ef
73eV
ωfel=92eV
2p6
2s2118eV
Monday, July 2, 12
Ef
2p6
2s2
ħω= 92 eV
L-edge shift
73eV
118eV
Monday, July 2, 12
Ef
93.5eV
ωfel=92eV
2p5
2s2
L-edge shift
Monday, July 2, 12
1x1012 1x1013 1x1014 1x1015 1x1016 1x10170
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Transm
issi
on
Experimental Data, binnedTheoretical transmission, 15fs pulseTheoretical transmission, 35fs pulse
Intensity (W/cm2)1x1012 1x1013 1x1014 1x1015 1x1016 1x10170
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Transm
issi
on
Experimental Data, binnedTheoretical transmission, 15fs pulseTheoretical transmission, 35fs pulse
Intensity (W/cm2)
1x1013 1x1014 1x1015 1x1016 1x10170
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Transm
issi
on
Experimental Data, binned
Intensity (W/cm2)
Aluminium Magnesium
Silicon Nitride
Cold transmission in the low intensity limit:- 52nm Al oxide: 16%- 52nm Mg + 20 nm Al + oxide: 10%- 83 nm SiN: 65%
Effective measure of the core-hole fraction!
Nagler et al. Nature Physics 5, 1341 (2009)
Saturable absorption in the XUV
Monday, July 2, 12
Temperature in Solid Aluminum Target
Monday, July 2, 12
Temperature in Solid Aluminum Target
Monday, July 2, 12
[email protected]!"#$%&'()*+,-!&.!$)/$".$0( 12
Gas monitor detectorMultilayer coated off-axis parabola
Target sample holder scans through focus
XUV spectrometer
FLASH @ 92 eV5 mm
Experimental setup
Monday, July 2, 12
Probing Warm Dense Matter on FLASH: L-shell spectroscopy
FEL photon excited a L-shel core stateħω= 92 eV
Solid, crystallinealuminium
Emitted photons map the occupancy ofthe valence band
ħω
L-shell photo-excitation Radiative recombination
Monday, July 2, 12
‣ Scanned 3 orders of magnitude in intensity
‣ Fluorescence overlaps with atomic emission lines from dilute plasma
‣ Valence band emission takes place ~40 fs after the first arrival of FEL pulse
‣ Measures the average temperature and density immediately after the pulse
‣ Vinko et al., PRL 104, 225001 (2010)
classical plasma
denseplasma
Γ = 1
Γ = 10
Density ( g/cm3)
103
104
101
102
102 10410010-4 10-2 1
Γ = 100
highdensitymatterTe
mpe
ratu
re (e
V)
55 60 65 70 75 80Energy (eV)
T=0.4 eV
T=0.8 eV
T=0.9 eV
T=1.1 eV
5.7 1012 W/cm2
2.0 ×1013 W/cm2
4.3 ×1013 W/cm2
1.5 ×1014 W/cm2
9.3 ×1014 W/cm2
3.4 ×1015 W/cm2
5.1 ×1015 W/cm2
Inte
nsi
ty /
Energ
y3
Al IVemission lines
Monday, July 2, 12
LCLS:SXR experimental setup
X-ray spectrometer: Al K-alpha emission 1460–1680 eV
LCLS pulse
Photon energy: 1560–1830 eVPulse length < 80 fs Pulse Energy ~1.5 mJBandwidth ~ 0.4%
Peak Intensity ~1017 W cm-2
CCD
Diode
ADP (101)crystal
36
1 micron thick Al sample
S. Vinko, Nature 482 (2012) 59-62
Monday, July 2, 12
37
K-edge
L-edge
ωp
σff(µm
-1)
Ephot
1s2
3s2 3p1
2p6
2s2 2p6
LCLS
Electronic structure of Aluminium
K: 1s2
L: 2s2 2p6
Photo-excitation
Neutral Al
Monday, July 2, 12
38
K-edge
L-edge
ωp
σff(µm
-1)
Ephot
1s2
3s2 3p1
2p6
2s2 2p6
LCLS
Electronic structure of Aluminium
Neutral Al
K: 1s1
L: 2s2 2p6
K-alpha emission
Monday, July 2, 12
39
K-edge
L-edge
ωp
σff(µm
-1)
Ephot
1s2
3s2 3p1
2p6
2s2 2p6
LCLS
Electronic structure of Aluminium
K: 1s2
L: 2s2 2p3
Photo-excitation
Ionized Al
Monday, July 2, 12
40
K-edge
L-edge
ωp
σff(µm
-1)
Ephot
1s2
3s2 3p1
2p6
2s2 2p6
LCLS
Electronic structure of Aluminium
Ionized Al
K: 1s1
L: 2s2 2p3
K-alpha emission
Monday, July 2, 12
K-shell spectroscopy of Hot Dense Aluminium
41
K-shell
L-shell
Continuum level
Conduction band
K-alpha VII
1450 1500 1550 1600 1650 1700 1750
Photon Energy (eV)
Inte
nsi
ty (a.u
.)
FEL photon energy: 1830 eV
IV
V
VIVII
VIIIIX
XIX
K-alpha emission
Physical recombination process
double K holessingle K holes
VVI
VIIVIII
IXX
S. Vinko, Nature 482 (2012) 59-62
Monday, July 2, 12
K-shell spectroscopy of Hot Dense Aluminium
42
1460 1480 1500 1520 1540 1560 1580 1600 1620 1640 1660 1680 1700
Photon Energy (eV)
Inte
nsi
ty (lo
g a
.u.)
1578 eV
1602 eV
1628 eV
1653 eV
1679 eV
1702 eV
1727 eV
1753 eV
1767 eV
1803 eV
1826 eV
VVI VII VIII IX X XI
V VI VII VIII IX X
IV
Monday, July 2, 12
Experimental Data
‣ FEL jitter seen to be significant - strong dependence of emission spectra on the excitation wavelengths warrants binning the results in wavelength
43
Because of large jitter in the FEL photon energy, averaging all data in the each run causes large effective bandwidths (~15eV)!
50
40
30
20
10
0
# of
sho
ts
185018001750170016501600FEL photon energy (hv) [eV]
above edge pumping (run 54~72)FEL hv distribution
xrayEtable_above_edge_hist average hv for each run
54/56 57/58 59/60 61/63 64 65 66 67 68/69 70/71 72 !Run!
Pumping photon energies!Step size of histogram : 5eV!
Monday, July 2, 12
K-shell spectroscopy of Hot Dense Aluminium
44Emitted photon energy (eV)
Ener
gy o
f x−r
ay F
EL e
xcita
tion
(eV)
1460 1480 1500 1520 1540 1560 1580 1600 1620 1640 1660 16801560
1580
1600
1620
1640
1660
1680
1700
1720
1740
1760
1780
1800
1820
100000
300000
1e+06
3e+06
1e+07
3e+07
Emitted photon energy (eV)
Ener
gy o
f x−r
ay F
EL e
xcita
tion
(eV)
1460 1480 1500 1520 1540 1560 1580 1600 1620 1640 1660 16801560
1580
1600
1620
1640
1660
1680
1700
1720
1740
1760
1780
1800
1820
100000
300000
1e+06
3e+06
1e+07
3e+07I-IV V VI VII VIII IX X XI
X-r
ay
FE
L p
ho
ton e
nerg
y (e
V)
Em
itted
pho
ton n
um
ber (sr -1 e
V -1)
II-V VI VII VIII
1!105
3!105
1!106
3!106
1!107
3!107
Emitted photon energy (eV)
IX X
S. Vinko, Nature 482 (2012) 59-62
Monday, July 2, 12
Charge state distribution - CSD
45
0 1 2 3 4 5 6 7 8 9 10 11 12 13
Charge state
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
Fra
ctio
nal y
ield
inte
gra
ted
ove
r p
uls
e
1580 eV1630 eV1680 eV1730 eV1780 eV1830 eV
S. Vinko, Nature 482 (2012) 59-62
Monday, July 2, 12
K-shell spectroscopy of Hot Dense Aluminium
46Emitted photon energy (eV)
Ener
gy o
f x−r
ay F
EL e
xcita
tion
(eV)
1460 1480 1500 1520 1540 1560 1580 1600 1620 1640 1660 16801560
1580
1600
1620
1640
1660
1680
1700
1720
1740
1760
1780
1800
1820
100000
300000
1e+06
3e+06
1e+07
3e+07IV V VI VII VIII IX X XI
Resonance transitio
ns
X-ra
y FE
L ph
oton
ene
rgy
(eV)
Emitted photon num
ber (sr -1 eV -1)
V VI VII VIII
1×105
3×105
1×106
3×106
1×107
3×107
Emitted photon energy (eV)
IX X
K-edge
S. Vinko, Nature 482 (2012) 59-62
Monday, July 2, 12
47
Electronic structure of Aluminium
K: 1s2
L: 2s2 2p3
Photo-excitation
K: 1s1
L: 2s2 2p3
K-alpha emission
Monday, July 2, 12
CSD and emission spectrum
48
0 1 2 3 4 5 6 7 8 9 10 11 12 13
Charge state
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
Fra
ctio
nal y
ield
inte
gra
ted
ove
r p
uls
e
1580 eV1630 eV1680 eV1730 eV1780 eV1830 eV
Emitted photon energy (eV)
Ener
gy o
f x−r
ay F
EL e
xcita
tion
(eV)
1460 1480 1500 1520 1540 1560 1580 1600 1620 1640 1660 16801560
1580
1600
1620
1640
1660
1680
1700
1720
1740
1760
1780
1800
1820
100000
300000
1e+06
3e+06
1e+07
3e+07IV V VI VII VIII IX X XI
Resonance transitio
ns
X-ra
y FE
L ph
oton
ene
rgy
(eV)
Emitted photon num
ber (sr -1 eV -1)
V VI VII VIII
1×105
3×105
1×106
3×106
1×107
3×107
Emitted photon energy (eV)
IX X
K-edge
S. Vinko, Nature 482 (2012) 59-62
Monday, July 2, 12
0 20 40 60 80 100 120 140 160Time (fs)
0
50
100
150
200
Tem
pera
ture
(eV)
Plasma parameters: electron temperature
49
0 1 2 3 4 5 6 7 8 9 10 11 12 13
Charge state
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
Fra
ctio
nal y
ield
inte
gra
ted
ove
r p
uls
e
1580 eV1630 eV1680 eV1730 eV1780 eV1830 eV
S. Vinko, Nature 482 (2012) 59-62
Monday, July 2, 12
0 20 40 60 80 100 120 140 160
Time (fs)
1x1023
2x1023
3x1023
4x1023
5x1023
6x1023
Densi
ty (ele
ctr
ons
cm
-3)
Plasma parameters: free-electron density
50
Ion density of solid-state Al (2.7 g cm-3)
0 1 2 3 4 5 6 7 8 9 10 11 12 13
Charge state
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
Fra
ctio
nal y
ield
inte
gra
ted
ove
r p
uls
e
1580 eV1630 eV1680 eV1730 eV1780 eV1830 eV
S. Vinko, Nature 482 (2012) 59-62
Monday, July 2, 12
Conclusions
‣ First experimental results looking at high-intensity X-ray FEL interaction with solid density Al samples: dynamics are very different to single-atom case;
‣ Electron collisional processes dominate the CSD, even in the presence of the intense X-ray pulse;‣ simulations indicate ‘thermal’ CSD within a fraction of the pulse
‣ Temperatures in excess of 150-200 eV achieved at solid densities;
‣ Absorption/heating determined by the ionized states, ground-state cross sections largely irrelevant!
‣ Emission spectrum generated by a quasi-monochromatic X-ray pulse is not necessarily representative of the CSD, but is sensitive to the K-edges of the excited system.
51
Monday, July 2, 12
Shock physics and Equations of State
52
Z
NPT
shock velocity
Monday, July 2, 12
Shock physics and Equations of State
53
Z
Density
shock velocity
Continuity of Mass, Momentum, Energy over shock front
3 equations, 5 unknowns
Monday, July 2, 12
Line-imaging velocimeter for shock diagnostics, P. Celliers et al., Rev. Sci. Instr., 4916, 75, (2004)Courtesy of Wark et al.
VISAR diagnostic for High Pressure Physics
F(r)
Monday, July 2, 12
Conclusion
X-ray FELs are a game changing tool in MEC science
Monday, July 2, 12