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Dynamic tunnelling ionization of $H_2^+$ in intense fields

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 نشر من قبل Liang-You Peng
 تاريخ النشر 2004
  مجال البحث فيزياء
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Intense-field ionization of the hydrogen molecular ion by linearly-polarized light is modelled by direct solution of the fixed-nuclei time-dependent Schrodinger equation and compared with recent experiments. Parallel transitions are calculated using algorithms which exploit massively parallel computers. We identify and calculate dynamic tunnelling ionization resonances that depend on laser wavelength and intensity, and molecular bond length. Results for $lambda sim 1064$ nm are consistent with static tunnelling ionization. At shorter wavelengths $lambda sim 790 $ nm large dynamic corrections are observed. The results agree very well with recent experimental measurements of the ion spectra. Our results reproduce the single peak resonance and provide accurate ionization rate estimates at high intensities. At lower intensities our results confirm a double peak in the ionization rate as the bond length varies.

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