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arXiv · 2002.05040

Transient optical gain in strong-field-excited solids

Muhammad Qasim·Dmitry A. Zimin·Vladislav S. Yakovlev
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Abstract

Multiphoton excitation of a solid by a few-cycle, intense laser pulse forms a very non-equilibrium distribution of charge carriers, where occupation probabilities do not necessarily decrease with energy. We show that, under certain conditions, significant population inversion can emerge between pairs of valence- or conduction-band states, where transitions between the Bloch states are dipole-allowed. This population inversion leads to stimulated emission in a laser-excited solid at frequencies where the unperturbed solid is transparent. We establish the optimal conditions for observing the strong-field-induced optical gain.

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Muhammad Qasim, Dmitry A. Zimin, Vladislav S. Yakovlev. 2020-02-12. Transient optical gain in strong-field-excited solids. https://doi.org/10.1103/physrevlett.127.087401

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