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arXiv · 2102.11208

High harmonics from backscattering of delocalized electrons

Chuan Yu·Ulf Saalmann·Jan M. Rost
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Abstract

It is shown that electron backscattering can enhance high-harmonic generation in periodic systems with broken translational symmetry. Paradigmatically, we derive for a finite chain of atoms the harmonic cutoff due to electrons backscattered from the edges of the chain and demonstrate a maximum in the harmonic yield if twice the quiver amplitude of the driven electrons equals the chain length. For an intuitive understanding of our quantum results we develop a refined semiclassical trajectory model with finite electron-hole separation after tunneling. We demonstrate that the same "tunnel exit" also holds for interband harmonics in conventional periodic solid-state systems.

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Chuan Yu, Ulf Saalmann, Jan M. Rost. 2021-02-22. High harmonics from backscattering of delocalized electrons. https://doi.org/10.1103/physreva.105.l041101

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