High Harmonic Analysis

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High Harmonic Analysis Using a COLTRIMS
Technique Ben Gramkow November 2, 2005
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(No Transcript)
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Outline

• COLTRIMS
• High Harmonics
• Pump-Probe Experiment

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Outline

• COLTRIMS
• High Harmonics
• Pump-Probe Experiment

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COLTRIMS
COLd Target Recoil-Ion Momentum Spectroscopy

• Spectrometer
• Detectors
• Magnetic Collection Field
• Target Jets
• Vacuum System

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COLTRIMS
Spectrometer Detectors
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COLTRIMS
COLd Target Recoil-Ion Momentum Spectroscopy

• Spectrometer
• Detectors
• Magnetic Collection Field
• Target Jets
• Vacuum System

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COLTRIMS
Spectrometer
E-field
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COLTRIMS
COLd Target Recoil-Ion Momentum Spectroscopy

• Spectrometer
• Detectors
• Magnetic Collection Field
• Target Jets
• Vacuum System

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COLTRIMS
Detectors
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COLTRIMS
COLd Target Recoil-Ion Momentum Spectroscopy

• Spectrometer
• Detectors
• Magnetic Collection Field
• Target Jets
• Vacuum System

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COLTRIMS
Magnetic Collection Field
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COLTRIMS
COLd Target Recoil-Ion Momentum Spectroscopy

• Spectrometer
• Detectors
• Magnetic Collection Field
• Target Jets
• Vacuum System

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COLTRIMS
Target Jet
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COLTRIMS
COLd Target Recoil-Ion Momentum Spectroscopy

• Spectrometer
• Detectors
• Magnetic Collection Field
• Target Jets
• Vacuum System

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COLTRIMS
Vacuum System
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COLTRIMS
Vacuum System
1.2x10-5 torr
2.7x10-8 torr
0.44 torr
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Outline

• COLTRIMS
• High Harmonics
• Pump-Probe Experiment

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High Harmonic Generation

• Three Step HHG Model
• Ionization
• Free Electron Motion
• Recombination
• High Harmonic Analysis
• Divergence
• Harmonic Content
• Flux

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High Harmonic Generation

• Three Step HHG Model
• Ionization
• Free Electron Motion
• Recombination
• High Harmonic Analysis
• Divergence
• Harmonic Content
• Flux

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High Harmonic Generation
Ionization
1014 - 1015 W/cm2
gt 1015 W/cm2
lt 1014 W/cm2
Multi-photon Processes (ATI)
Tunneling Ionization
Over the Barrier Ionization
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High Harmonic Generation

• Three Step HHG Model
• Ionization
• Free Electron Motion
• Recombination
• High Harmonic Analysis
• Divergence
• Harmonic Content
• Flux

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High Harmonic Generation
Free Electron Motion
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High Harmonic Generation

• Three Step HHG Model
• Ionization
• Free Electron Motion
• Recombination
• High Harmonic Analysis
• Divergence
• Harmonic Content
• Flux

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High Harmonic Generation
Recombination

• Two photons per optical cycle
• Doubled frequency separation

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High Harmonic Generation

• Three Step HHG Model
• Ionization
• Free Electron Motion
• Recombination
• High Harmonic Analysis
• Divergence
• Harmonic Content
• Flux

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High Harmonic Analysis
Divergence
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High Harmonic Analysis
Divergence
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High Harmonic Analysis
Divergence
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High Harmonic Generation

• Three Step HHG Model
• Ionization
• Free Electron Motion
• Recombination
• High Harmonic Analysis
• Divergence
• Harmonic Content
• Flux

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High Harmonic Analysis
Harmonic Content
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High Harmonic Analysis
Time of Flight Spectra
Electrons
Recoil Ions
Time of Flight ns
Time of Flight ns
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High Harmonic Analysis
Wiggle Spectrum
Time of Flight ns
Time of Flight ns
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High Harmonic Analysis
Momentum Spectra
Pz vs. Px a.u.
Pz vs. Py a.u.
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High Harmonic Analysis
Photoelectron Energy Spectrum
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High Harmonic Generation

• Three Step HHG Model
• Ionization
• Free Electron Motion
• Recombination
• High Harmonic Analysis
• Divergence
• Harmonic Content
• Flux

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High Harmonic Analysis
Flux

• Two orders of magnitude low
• We have not sought to maximize it.

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Outline

• COLTRIMS
• High Harmonics
• Pump-Probe Experiment

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Pump-Probe Experiment

• Laser pump, x-ray probe
• Well-defined probe energy
• Valence Electrons
• Inner-Shell Electrons

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Pump-Probe Experiment
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Pump-Probe Experiment
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Closing Remarks
Our high harmonics can be examined with
COLTRIMS. Our laser pulse duration and intensity
lets follow the dynamics of the lightest
molecules.
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Equations and Parameters
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Free Electron Motion
Ekin, max 3.17 Up
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Harmonic Sources
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Photoelectron Energy Spectrum
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Photoelectron Energy Spectrum
Harmonic Order
11th 13th 15th 17th 19th 21st 23rd 25th
Ehn eV 17.05 20.15 23.25 26.35 29.45 32.55 36.65 39.75
Ehn - Ip eV 1.35 4.45 7.55 10.65 13.75 16.85 19.95 23.05
p a.u. 0.31 0.57 0.74 0.88 1.01 1.11 1.21 1.3
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Photoelectron Energy Spectrum
11th 13th 15th 17th 19th 21st 23rd 25th
Ehn eV 17.05 20.15 23.25 26.35 29.45 32.55 36.65 39.75
Ehn - Ip eV 1.35 4.45 7.55 10.65 13.75 16.85 19.95 23.05
p a.u. 0.31 0.57 0.74 0.88 1.01 1.11 1.21 1.3
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Equations and Parameters