Tracking ultrafast solid-state dynamics using high harmonic spectroscopy

Mina R. Bionta; Elissa Haddad; Adrien Leblanc; Vincent Gruson; Philippe Lassonde; Heide Ibrahim; Jérémie Chaillou; Nicolas Émond; Martin R. Otto; Bradley J. Siwick; Mohamed Chaker; François Légaré

doi:10.1103/physrevresearch.3.023250

arXiv · 2003.10430

Tracking ultrafast solid-state dynamics using high harmonic spectroscopy

Mina R. Bionta·Elissa Haddad·Adrien Leblanc·Vincent Gruson·Philippe Lassonde·Heide Ibrahim·Jérémie Chaillou·Nicolas Émond·Martin R. Otto·Bradley J. Siwick·Mohamed Chaker·François Légaré

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Abstract

We establish time-resolved high harmonic generation (tr-HHG) as a powerful spectroscopy for photoinduced dynamics in strongly correlated materials through a detailed investigation of the insulator-to-metal transitions in vanadium dioxide. We benchmark our technique by comparing our measurements to established momentum-resolved ultrafast electron diffraction, and theoretical density functional calculations. Tr-HHG allows distinguishing of individual dynamic channels, including a transition to a thermodynamically hidden phase. In addition, the HHG yield is shown to be modulated at a frequency characteristic of a coherent phonon in the equilibrium monoclinic phase over a wide range of excitation fluences. These results demonstrate that tr-HHG is capable of tracking complex dynamics in solids through its sensitivity to the band structure.

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Mina R. Bionta, Elissa Haddad, Adrien Leblanc, Vincent Gruson, Philippe Lassonde, Heide Ibrahim, Jérémie Chaillou, Nicolas Émond, Martin R. Otto, Bradley J. Siwick, Mohamed Chaker, François Légaré. 2020-03-23. Tracking ultrafast solid-state dynamics using high harmonic spectroscopy. https://doi.org/10.1103/physrevresearch.3.023250

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