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arXiv · 0709.3861

Amplification of High Harmonics Using Weak Perturbative High Frequency Radiation

Avner Fleischer·Nimrod Moiseyev
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Abstract

The mechanism underlying the substantial amplification of the high-order harmonics q \pm 2K (K integer) upon the addition of a weak seed XUV field of harmonic frequency qωto a strong IR field of frequency ωis analyzed in the framework of the quantum-mechanical Floquet formalism and the semiclassical re-collision model. According to the Floquet analysis, the high-frequency field induces transitions between several Floquet states and leads to the appearance of new dipole cross terms. The semiclassical re-collision model suggests that the origin of the enhancement lies in the time-dependent modulation of the ground electronic state induced by the XUV field.

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Avner Fleischer, Nimrod Moiseyev. 2007-09-25. Amplification of High Harmonics Using Weak Perturbative High Frequency Radiation. https://doi.org/10.1103/physreva.77.010102

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