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arXiv · 2308.04631

Decoding phase and time-dependent interferograms of high-order harmonics

C. Granados·Ching-Ling Hsiao·Marcelo F. Ciappina·Khadga J. Karki
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Abstract

Interferometric measurements of high-harmonics induced by multiple laser fields in an emerging field of research that promises optimized yield of harmonics, and time and space-resolved nonlinear spectroscopy. Most of the measurements have been done by controlling the time-delay between the pulses. Here, we show that by changing one additional parameter, i.e. the phase-difference between the fields, together with the time-delay, one can, on the one hand, enhance the harmonic yield and, on the other hand, obtain in-depth information about the physical mechanisms that control the electron trajectories contributing to the high-harmonic generation. The two-dimensional interferograms obtained from such investigations can be used to find the values of time-delay and phase between the laser fields that maximize the yield of a particular harmonic. Results show that maximum yields of certain harmonics can be orders of magnitude larger than when using a single field or two fields with zero time-delay and phase difference. Our high-harmonics two-dimensional interferograms-based method paves the way for a simpler analysis of the attosecond electron dynamics in complex molecules and solids.

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C. Granados, Ching-Ling Hsiao, Marcelo F. Ciappina, Khadga J. Karki. 2023-08-08. Decoding phase and time-dependent interferograms of high-order harmonics. https://arxiv.org/abs/2308.04631

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