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TTF FEL Results
Jacek Krzywinski
• TTF FEL Performance
•FEL Physics Experiments
•FELIS (Free Electron Laser -Interaction with Solids
•|Cluster Experiment
TTF FEL Performance
Photon Beam Diagnostic TeamScientists:
Josef FeldhausChristofer Gerth
Ulrich HahnRasmus Ischebeck
Barbara SteegKai TiedkeRolf Treush
Engineers and Technicians:Lutz Bittner
Thorsten HansMathias HesseFini Jastrow
Michael MeschkatErnst Weiner
Saturation: from 80-120 nm
Tranverse coherence > 90%
Diffraction patterns from double and crossed slits
Variation of pulse length: 50 - 100 fs
variation via bunch compressor 1
Second harmonics spectra:
wavelength 48.5 nm
Demonstration of:
J. Krzywinski 1,2, A. Andrejczuk 1,3, U. Hahn 2, M. Kirm 4, A. Kauch 5,M. Jurek 1,2, J.B. Pelka 1, H. Reniewicz 3 ,W. Sobala 6, M. Sikora 7,
R. Sobierajski 2,8
1Institute of Physics, Polish Academy of Sciences,2HASYLAB at DESY, Germany,
3University of Bialystok, Poland,4Institut Für Eksperimentalphysik der Hamburg Universität
5Warsaw University,Poland6Institute of Nuclear Physics, Cracow,Poland
7University of Mining and Metallurgy8Warsaw University of Technology, Cracow, Poland
FELIS(Free Electron Laser-Interaction with Solids)
Experimental layout
TOF
Evaporation cell
CCD CameraLight source
VUV Detectors
VUVlaser beam
X,Y,Z,ϕsample manipulator
APhotocurrent
Experimental layout
VUV beam parameters
Pulse length 30-100 fsPulse energy 1- 30 uJWavelength 89-98 nmMinimum spot size 10 µm
Experimental results Example of ablation detected by TOF spectrometer (Si sample)
0 1 2 3 4 5 6 7-0.04
-0.02
0
0.02
0.04
0.06
0.08
0.1
0.12
Time [µs]
TOF signal [V]
Si+
O+
H+
0.1 0.2 0.3 0.4 0.5 0.6
0
0.2
0.4
0.6
0.8
1
Beam intensity [a.u.]
Normalized inte gral of MCP signal [a . u . ]
Experimental results Si+ ion emission threshold
0 2 4 6 8 100
2
4
6
8
10
Pulse energy [uJ]
Num
ber
of p
ulse
s max = 2.5uJmean = 1.2uJNpulses = 10
∆=2.5mmSi
0 2 4 6 8 100
2
4
6
8
10
Pulse energy [uJ]
Num
ber
of p
ulse
s max = 5.1uJmean = 1.3uJNpulses = 10
∆=1mmSi
0 2 4 6 8 100
2
4
6
8
10
Pulse energy [uJ]
Num
ber
of p
ulse
s max = 3.4uJmean = 1uJ
Npulses = 10
∆=0mm
Si
Si
C+
3C+
4C+
5C+
6C+
7C+
8C+
9C+
10C+
11C+
12C+ 14C+15C+
Cluster emission from graphite surface
Graphitehv = 10.1 eV
fluence ~0.1 J/cm^2
Cluster emission from MgF2 surface
Surface modification
AFM results
V. Kuestner, S. Jacobi, GKSS
C-film (10nm) / Si-substrate
C-film (10nm) / Si-substrate
C-film (10nm) / Si-substrate
C-film (40-nm) / Si-substrate
Plasma creation• multiple ionisation
• maximum kinetic energy > 10 keV (C5+)
• non thermal ion energy distribution
0 2 4 6 8 100
2
4
6
8
10
Pulse energy [uJ]
Num
ber
of p
ulse
s max = 5.4uJmean = 1.6uJNpulses = 10
∆=0mm
FELIS Jan. 2002
scan20020119163300_/t0 /set mass/charge scale /versus/ Max of I0 peak[V][]
0 50 100 150 200
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09TOF -scan20020119163300_023.dat /cond._2/t0
Mass/charge [amu/e]
Voltage [V]
scan20020119163000_/t0 /set mass/charge scale /versus/ Integ. of I0mcp-sc[V*s][]
0 50 100 150 200-0.06
-0.04
-0.02
0
0.02
0.04
0.06
0.08
0.1TOF -scan20020119163000_026.dat /cond._2/t0
Mass/charge [amu/e]
Voltage [V]
scan20020119163300_/t0 /set mass/charge scale /versus/ Max of I0 peak[V][]
0 50 100 150 200
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09TOF -scan20020119163300_037.dat /cond._2/t0
Mass/charge [amu/e]
Voltage [V]
scan20020119163700_/t0 /set mass/charge scale /versus/ Max of I0 peak[V][]
0 50 100 150 200
-0.01
0
0.01
0.02
0.03
0.04
TOF -scan20020119163700_037.dat /cond._2/t0
Mass/charge [amu/e]
Voltage [V]
Au+
Au+
Au+Au+
Au 2+
Au 2+
Au 2+
Au 2+
Au 3+
Au 3+
Au 3+
Au 3+
plasma results Au bulk
HPF=100 V HPF=200V
HPF=200V HPF=800V
First Results from theClusterexperiment at the TTF-FEL
• Motivation
• Experimental Set-Up
• Multi-Photon Ionisation
• Coulomb Explosion of Clusters
Peter GürtlerWiebke LaaschTim LaarmannJoachim SchulzAnja SwiderskiKlaus von HaeftenHubertus WabnitzThomas Möller
Idea of the experimentinteraction of intense soft x-rays with matter
which multi-photon processes are observed
• cross sections (surface, bulk)
• which ions are prepared (charge state, electronically excited states)
• life time of intermediate states
• high-order harmonicgeneration
0 100 200 300 400 500 600 700 800
0,0
0,2
0,4
single shot
average size of clustersN=300
7+6+
8+
5+
4+
Xe++
Xe3+
Xe+
inte
nsity
[arb
. uni
ts]
time of flight [ns]
0 200 400 600 800
0,0
0,1
0,2
0,3
atomic beam
Xe+
inte
nsity
[arb
. uni
ts]
time of flight [ns]
0 200 400 600 800
0,0
0,1
0,2
0,3
ejection energy
average size of clustersN=20
4+
Xe++
Xe3+
Xe2+
Xe+
inte
nsity
[arb
. uni
ts]
time of flight [ns]
0 100 200 300 400 500 600 700 800
0,0
0,1
0,2
0,3
cluster beam
5+
6+7+
8+
4+
Xe++
Xe3+
Xe+
average size of clustersN=2000
inte
nsity
[arb
. uni
ts]
time of flight [ns]
0 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0 6 0 0 7 0 00 . 0
0 . 1
0 . 2
0 . 3
X e +
inte
nsity
[arb
. uni
ts]
t i m e o f f l i g h t [ n s ]
a t o m
0 . 0
0 . 1
0 . 2
0 . 3
0 . 4
6 +7 +
X e 3 +
8 +
X e ++
N ~ 2 - 2 0
0 . 0
0 . 1
0 . 2
0 . 3
0 . 4
5+
4 +
N ~ 8 0
0 . 0
0 . 1
0 . 2
0 . 3
0 . 4
0 . 5
4 238765 1
N ~ 3 0 0 0 0 Dependence on the cluster size
• Single photon absorption in Xe atoms
• emission of highly charge ions from clusters ( up to eight times charges)
• ions have high kinetic energy
1 2 3 4 5 6 70
500
1000
1500
2000
2500
ejec
tion
ener
gy [e
V]
ion charge state
xenon clustersN=2000
Kinetic energy of the ejected ions
• Quadratic dependence on charge
• Coulomb explosion
0 200 400 600 800
Dependence on the power density
Xenon clusters, 50 atoms
1013 Watt/cm2
5*1011 Watt/cm2
Conclusions:
• all features of FEL SASE radiation has been demonstrated in the80-100 nm range : saturation, tunability, coherence, higherharmonics (in addition pulse length control in the 50- 100 fs range)
• two user experiments has been successfully carried out providingunique data of intense soft X-ray - matter interaction in the new domain of parameters
• results of the experiments are essential for planningfuture experiments at soft X-ray FELs