Polarization and dissociation of a high energy photon-excited state in conjugated polymers

• We explore the polarization of a high energy photon-excited state in polymers.
• An obvious reverse polarization under the moderate electric field is obtained.
• High energy photon-excited state is dissociated into polaron pair at strong field.
• Increasing electron–electron interaction will weaken the reverse polarization.
• Interchain coupling induces dissociation into high-energy exciton and solitons.

We use the tight-binding Su–Schrieffer–Heeger model for the one-dimensional conjugated polymers to explore the static polarization behavior of a high energy photon-excited state under the electric field. An obvious reverse polarization is obtained although the electric field is weak. With the increase of field strength, the degree of polarization increases first and then decreases. When the electric field is strong enough, the excited state is dissociated into the polaron pair. In addition, the effects of electron–electron interaction and interchain coupling are also discussed. The results indicate that the electron–electron interaction could weaken the reverse polarization of the high energy photon-excited state, which tends to be dissociated into a high-energy exciton and a pair of solitons with the including of interchain coupling.