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arXiv · 1011.5701

Photoinduced coherent oscillations in the one-dimensional two-orbital Hubbard model

Nobuya Maeshima·Ken-ichi Hino·Kenji Yonemitsu
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Abstract

We study photoinduced ultrafast coherent oscillations originating from orbital degrees of freedom in the one-dimensional two-orbital Hubbard model. By solving the time-dependent Schrödinger equation for the numerically exact many-electron wave function, we obtain time-dependent optical response functions. The calculated spectra show characteristic coherent oscillations that vary with the frequency of probe light. A simple analysis for the dominant oscillating components clarifies that these photoinduced oscillations are caused by the quantum interference between photogenerated states. The oscillation attributed to the Raman-active orbital excitations (orbitons) clearly appears around the charge-transfer peak.

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Nobuya Maeshima, Ken-ichi Hino, Kenji Yonemitsu. 2010-11-26. Photoinduced coherent oscillations in the one-dimensional two-orbital Hubbard model. https://doi.org/10.1103/physrevb.82.161105

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