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Coherent nuclear motion in a condensed-phase environment: Wave-packet approach and pump-probe spectroscopy

L. Muhlbacher·A. Lucke·R. Egger
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Abstract

A quantum-mechanical Gaussian wave-packet approach to the theoretical description of nuclear motions in a condensed-phase environment is developed. General expressions for the time-dependent reduced density matrix are given for a harmonic potential surface, and the exact quantum dynamics is found for a microscopic system-plus-bath model. Particular attention is devoted to the influence of initial correlations between system and bath for the outcome of a pump-probe experiment. We show that the standard factorized preparation, compared to a more realistic correlated preparation, leads to significantly different stimulated emission spectra at high temperatures. Recent experiments for the reaction center are analyzed using this formalism.

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L. Muhlbacher, A. Lucke, R. Egger. 1999-01-13. Coherent nuclear motion in a condensed-phase environment: Wave-packet approach and pump-probe spectroscopy. https://doi.org/10.1063/1.478484

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