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arXiv · 1702.04495

Intense keV isolated attosecond pulse generation by orthogonally polarized multicycle midinfrared two-color laser field

Guicun Li·Yinghui Zheng·Zhinan Zeng·Ruxin Li
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Abstract

We theoretically investigate the generation of intense keV attosecond pulses in an orthogonally polarized multicycle midinfrared two-color laser field. It is demonstrated that multiple continuum-like humps, which have a spectral width of about twenty orders of harmonics and an intensity of about one order higher than adjacent normal harmonic peaks, are generated under proper two-color delays, owing to the reduction of the number of electron-ion recollisions and suppression of inter-half-cycle interference effect of multiple electron trajectories when the long wavelength midinfrared driving field is used. Using the semiclassical trajectory model, we have revealed the two-dimensional manipulation of the electron-ion recollision process, which agrees well with the time frequency analysis. By filtering these humps, intense isolated attosecond pulses are directly generated without any phase compensation. Our proposal provides a simple technique to generate intense isolated attosecond pulses with various central photon energies covering the multi-keV spectral regime by using multicycle driving pulses with high pump energy in experiment.

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Guicun Li, Yinghui Zheng, Zhinan Zeng, Ruxin Li. 2017-02-15. Intense keV isolated attosecond pulse generation by orthogonally polarized multicycle midinfrared two-color laser field. https://doi.org/10.3788/col201715.071901

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