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arXiv · 1504.01458

Femtosecond time-resolved dynamical Franz-Keldysh effect

T. Otobe·Y. Shinohara·S. A. Sato·K. Yabana
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Abstract

We theoretically investigate the dynamical Franz-Keldysh effect in femtosecond time resolution, that is, the time-dependent modulation of a dielectric function at around the band gap under an irradiation of an intense laser field. We develop a pump-probe formalism in two distinct approaches: first-principles simulation based on real-time time-dependent density functional theory and analytic consideration of a simple two-band model. We find that, while time-average modulation may be reasonably described by the static Franz-Keldysh theory, a remarkable phase shift is found to appear between the dielectric response and the applied electric field.

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T. Otobe, Y. Shinohara, S. A. Sato, K. Yabana. 2015-04-07. Femtosecond time-resolved dynamical Franz-Keldysh effect. https://doi.org/10.1103/physrevb.93.045124

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