Diagnosis of a High Harmonic Beam Using

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Kansas State University Department of Physics
Diagnosis of a High Harmonic Beam Using COLTRIMS
Predrag Ranitovic
April 2005
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Outline
1. Motivation
Time resolved photoelectron spectroscopy
Development of an apparatus for performing
pump-probe experiments
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Development of an apparatus for performing
pump-probe experiments
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Outline
1. Motivation
Time resolved photoelectron spectroscopy
Development of an apparatus for performing
pump-probe experiments
Development of an apparatus for performing
pump-probe experiments
Generation and Characterization of a High
Harmonic Beam
2. Summary and Outlook
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Experimental Setup
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High Harmonic Generation
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High Harmonic Generation
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High Harmonic Generation
Gas Tube
Argon gas as a harmonic generation medium
Harmonics intensity varies with the lasers
focusing point
Al filter
Aluminum absorber
? 800 nm
? ? 40 fs,
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High Harmonic Generation
Aluminum absorber
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High Harmonic Generation
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COLTRIMS
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COLTRIMS Momentum Imaging Technique
Mono energetic electron with the momentum along
the spectrometer electric field
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Ar time of flight and detector image
y mm/2
t ns
x mm/2
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Electron time of flight and detector image
B 12 Gauss
y mm/2
t ns
x mm/2
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Electron time of flight and detector image
Electron time of flight and detector image
B 8 Gauss
y mm/2
t ns
x mm/2
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Electron time of flight and detector image
Electron time of flight and detector image
B 6 Gauss
y mm/2
t ns
x mm/2
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The Wiggles
r mm/2
r m
t ns
t s
T357.4/B ns
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Momentum Imaging
P
y
P a.u.
P a.u.
x
z
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Momentum Imaging
B 6 Gauss
P
P
x
y
P a.u.
P a.u.
z
z
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Momentum Imaging
B 8 Gauss
P
x
P a.u.
t ns
z
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Photoelectron energies

E eV
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Photoelectron energies
P
x
P a.u.
z
E eV
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Summary and Outlook
X-ray Angular Divergence
Photon flux
Harmonic Orders
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The Wiggles