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Collective oscillations driven by correlation in the nonlinear optical regime

Th. Oestreich·L. J. Sham
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Abstract

We present an analytical and numerical study of the coherent exciton polarization including exciton-exciton correlation. The time evolution after excitation with ultrashort optical pulses can be divided into a slowly varying polarization component and novel ultrafast collective modes. The frequency and damping of the collective modes are determined by the high-frequency properties of the retarded two-exciton correlation function, which includes Coulomb effects beyond the mean-field approximation. The overall time evolution depends on the low-frequency spectral behavior. The collective mode, well separated from the slower coherent density evolution, manifests itself in the coherent emission of a resonantly excited excitonic system, as demonstrated numerically.

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Th. Oestreich, L. J. Sham. 1999-10-11. Collective oscillations driven by correlation in the nonlinear optical regime. https://doi.org/10.1103/physrevlett.83.3510

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