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arXiv · 1402.3434

Quasi-phase-matching high-harmonic radiation using chirped THz pulses

Katalin Kovács·Emeric Balogh·János Hebling·Valer Tosa·Katalin Varjú
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Abstract

High-order harmonic generation in the presence of a chirped THz pulse is investigated numerically with a complete 3D non-adiabatic model. The assisting THz pulse illuminates the HHG gas cell laterally inducing quasi-phase-matching. We demonstrate that it is possible to compensate the phase mismatch during propagation and extend the macroscopic cutoff of a propagated strong IR pulse to the single-dipole cutoff. We obtain two orders of magnitude increase in the harmonic efficiency of cutoff harmonics ($\approx$170 eV) using a THz pulse of constant wavelength, and a further factor of 3 enhancement when a chirped THz pulse is used.

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Katalin Kovács, Emeric Balogh, János Hebling, Valer Tosa, Katalin Varjú. 2014-02-14. Quasi-phase-matching high-harmonic radiation using chirped THz pulses. https://doi.org/10.1103/physrevlett.108.193903

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