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arXiv · 1107.3609

Generation of isolated attosecond pulses in the far field by spatial filtering with an intense few-cycle mid-infrared laser

Cheng Jin·Anh-Thu Le·Carlos A. Trallero-Herrero·C. D. Lin
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Abstract

We report theoretical calculations of high-order harmonic generation (HHG) of Xe with the inclusion of multi-electron effects and macroscopic propagation of the fundamental and harmonic fields in an ionizing medium. By using the time-frequency analysis we show that the reshaping of the fundamental laser field is responsible for the continuum structure in the HHG spectra. We further suggest a method for obtaining an isolated attosecond pulse (IAP) by using a filter centered on axis to select the harmonics in the far field with different divergence. We also discuss the carrier-envelope-phase dependence of an IAP and the possibility to optimize the yield of the IAP. With the intense few-cycle mid-infrared lasers, this offers a possible method for generating isolated attosecond pulses.

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Cheng Jin, Anh-Thu Le, Carlos A. Trallero-Herrero, C. D. Lin. 2011-07-19. Generation of isolated attosecond pulses in the far field by spatial filtering with an intense few-cycle mid-infrared laser. https://doi.org/10.1103/physreva.84.043411

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