Comparison of He He to H2 H2

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Comparison of He/He to H2/H2
Comparison of He/He to H2/H2
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H2 in a Laser Field
Physical Processes

• Tunneling ionization
• Rescattering with ionic core
• Impact excitation
• Field ionization and dissociation.

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Tunneling Ionization
Effective Potential
Initial conditions
Classical trajectory
Regularized coordinates
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Impact Excitation
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Impact Excitation-II
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Impact Excitation Probability
Vibration wavepacket
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Field Ionization
?u totally ionized ?u partially ionized.
How far can proton move in one fs?
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Field Ionization-II
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Ionization versus Dissociation
Ionization Ei(R) V(R) V(Rj) 1/Rj 1/R
E(R) - E(Rj)
H2
Dissociation Ed(R) V(R) 0.5
Ed(R) ? Ei(R)
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Branch Ratio

• Total impact exication probability
• Branch ratio of the ionization and dissociation
• Alignment dependence for the ionization or
  dissociation
• .

Branch ratio of H2 in a laser field
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Ionization and Dissociation Spectra (Averaged)
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Comparing with Experiments
H. Niikura, Nature 417 (2002) 917.
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Ionization and Dissociation Spectra (Parallel)
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Ionization and Dissociation Spectra(Perpendicular
)
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Comparing with Experiments
From Lew Cockes Talk