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arXiv · 1305.4556

High-order harmonic generation from diatomic molecules in elliptically polarized driving fields: a generalized interference condition

T. Das·B. B. Augstein·C. Figueira de Morisson Faria
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Abstract

We investigate the influence of intense, elliptically polarized driving fields on high-order harmonic spectra from aligned diatomic molecules. We derive a generalized two-center interference condition for elliptically polarized fields, which accounts for s-p mixing and the orbital symmetry, within the strong-field and the single-active electron approximation. We show that the non-vanishing ellipticity introduces an effective dynamic shift in the angle for which the two-center interference maxima and minima occur, with regard to the existing condition for linearly polarized fields. This shift depends on the ratio between the field-dressed momentum components of the returning electron parallel and perpendicular to the major ellipticity axis along each possible orbit. Because of this dependence, we find that there will be a blurring in the two-center interference minima, and that increasing ellipticity leads to splitting in such patterns. These features are investigated in detail for H2 and Ar2.

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T. Das, B. B. Augstein, C. Figueira de Morisson Faria. 2013-05-20. High-order harmonic generation from diatomic molecules in elliptically polarized driving fields: a generalized interference condition. https://doi.org/10.1103/physreva.88.023404

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