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DOE OSTI · 1902165

Probing ultrafast excited-state dynamics using EUV-IR six-wave-mixing emission spectroscopy

Shalaby, Islam (ORCID:0000000332846636)·Chakraborty, Nisnat·Yanez-Pagans, Sergio·Wood, James·Biswas, Dipayan·Sandhu, Arvinder (ORCID:000000027876855X)
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Abstract

Non-linear processes such as four-wave-mixing have become instrumental in attosecond EUV spectroscopy. Using EUV high harmonics in conjunction with collinear near-infrared and mid-infrared fields, we extended this approach to high-order-mixing between three colors. Specifically, we find that atomic resonances in neon exhibit a significant cross section for six-wave mixing. The MIR probe frequency tunability in our multicolor scheme is employed to access several optically dark resonances and probe the quantum beat of a coherent electronic wavepacket using background-free EUV emission as a diagnostic. This technique can be easily extended to other atomic and molecular systems, and opens the door to multi-dimensional non-linear spectroscopy.

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74 ATOMIC AND MOLECULAR PHYSICSXUVattosecond spectroscopyfour-wave-mixingsix-wave-mixingultrafast

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Shalaby, Islam (ORCID:0000000332846636), Chakraborty, Nisnat, Yanez-Pagans, Sergio, Wood, James, Biswas, Dipayan, Sandhu, Arvinder (ORCID:000000027876855X). 2022-12-07. Probing ultrafast excited-state dynamics using EUV-IR six-wave-mixing emission spectroscopy. https://doi.org/10.1364/oe.478959

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