Controlling H2+ molecular harmonic radiation by spatial inhomogeneous field

Abstract

Abstract: Controlling the molecular harmonic generation and distribution from H2+ driven by the spatial inhomogeneous field have been theoretically investigated by solving the Non-Bohn-Oppenheimer time-dependent Schrodinger equation. It shows that when the laser field is larger than zero, the contribution from the negative-H to the harmonic spectrum is higher than that from the positive-H; when the laser field is smaller than zero, the contribution from the positive-H to the harmonic spectrum is higher than that from the negative-H. The harmonic cutoff can be extended when the spatial position of the inhomogeneous field is moving away from the center. However, the contribution from the negative-H to the higher harmonic orders will be decreased when the spatial position of the inhomogeneous field is chosen to be the negative value. The ionization probabilities, the time-frequency analyses of the harmonic spectra and the time-dependent wave functions have been shown to explain harmonic emission process. Finally, by superposing a properly selected harmonics, a 45 as pulse can be produced.

Key words: attosecond pulse

CLC Number:

O562.4

References

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