title: Dynamics of photogenerated polarons in conjugated polymers.
abstract: Within a tight-binding electron-phonon interacting model, we investigate the dynamics of photoexcitations to address the generation mechanism of charged polarons in conjugated polymers by using a nonadiabatic evolution method. Besides the neutral polaron exciton which is well known, we identify a novel product of lattice dynamic relaxation from the photoexcited states in a few hundreds of femtoseconds, which is a mixed state composed of both charged polarons and neutral excitons. Our results show that the charged polarons are generated directly with a yield of about 25%, which is independent of the excitation energies, in good agreement with results from experiments. Effects of the conjugation length are also discussed.
authors.affiliation: Research Center for Theoretical Physics, Fudan University, Shanghai 200433, China.
authors.forename: Z
authors.initials: Z
authors.lastname: An
authors.forename: C Q
authors.initials: CQ
authors.lastname: Wu
authors.forename: X
authors.initials: X
authors.lastname: Sun