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arXiv · 2307.00443

Controlling the Bandwidth of High Harmonic Emission Peaks with the Spectral Polarization of the Driver

Eldar Ragonis·Eran Ben Arosh·Lev Merensky·Avner Fleischer
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Abstract

We demonstrate a High-Harmonic-Generation scheme which offers control over the bandwidth of the spectral peaks. The scheme uses a vectorial two-color driver with close central frequencies, generated by spectrally splitting a linearly-polarized input femtosecond-duration laser pulse and subsequent recombining the two halves after their polarizations are made cross-elliptical and counter-rotating. This results in the generation of new emission channels which coalesce into broad odd-integer HHG peaks, the bandwidth of each being proportional to the frequency difference between the two colors, to the harmonic order and inversely-proportional to the driver fields' ellipticities. Peak-broadening to the extent that a supercontinuum is formed is also demonstrated. This source will find use in HHG applications benefiting from high-flux broadband extreme ultra-violet radiation, such as attosecond transient absorption spectroscopy.

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Eldar Ragonis, Eran Ben Arosh, Lev Merensky, Avner Fleischer. 2023-07-01. Controlling the Bandwidth of High Harmonic Emission Peaks with the Spectral Polarization of the Driver. https://arxiv.org/abs/2307.00443

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