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arXiv · 0707.2163

Phonon-driven ultrafast exciton dissociation at donor-acceptor polymer heterojunctions

Hiroyuki Tamura·John G. S. Ramon·Eric R. Bittner·Irene Burghardt
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Abstract

A quantum-dynamical analysis of phonon-driven exciton dissociation at polymer heterojunctions is presented, using a hierarchical electron-phonon model parameterized for three electronic states and 24 vibrational modes. Two interfering decay pathways are identified: a direct charge separation, and an indirect pathway via an intermediate bridge state. Both pathways depend critically on the dynamical interplay of high-frequency C=C stretch modes and low-frequency ring-torsional modes. The ultrafast, highly non-equilibrium dynamics is consistent with time-resolved spectroscopic observations.

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Hiroyuki Tamura, John G. S. Ramon, Eric R. Bittner, Irene Burghardt. 2007-07-14. Phonon-driven ultrafast exciton dissociation at donor-acceptor polymer heterojunctions. https://doi.org/10.1103/physrevlett.100.107402

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