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arXiv · 2111.08675

Atomic Floquet physics revealed by free electrons

Eduardo Arqué López·Valerio Di Giulio·F. Javier García de Abajo
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Abstract

We theoretically investigate the ability of free electrons to yield information on the nonlinear Floquet dynamics of atomic systems subject to intense external illumination. By applying a quantum-mechanical formalism to describe the atom-electron interaction under the presence of a monochromatic classical light field, we observe multiple energy features that reveal a large departure from non-illumination conditions in two- and three-level illuminated atoms, including the emergence of energy features associated with direct electron-photon exchanges, as well as a varied set of Floquet resonances that strongly depend on the light intensity and frequency. Our results unveil a wealth of effects associated with the interaction between free electrons and optically driven electronic systems.

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Eduardo Arqué López, Valerio Di Giulio, F. Javier García de Abajo. 2021-11-16. Atomic Floquet physics revealed by free electrons. https://doi.org/10.1103/physrevresearch.4.013241

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