Charge transport, especially soliton and polaron dynamics, is simulated for systems of coupled trans-polyacetylene chains using the Su-Schrieffer-Heeger model with an additional part to include an external electric field. We show that soliton-assisted interchain charge transport is not as likely as polaron interchain hopping. In systems with strong interchain interaction the two-dimensional (2D) polaron is stable in the unbiased case. However, when an external field is applied the 2D polaron becomes unstable for interchain migration, the charge is instead delocalized both along and between polymer chains. Thus, for well-ordered polymeric systems, which cannot be considered one dimensional, the transition to a metallic phase can occur at much lower doping levels than in systems for which the interchain coupling is less prominent.

• Received 4 July 2001

DOI:https://doi.org/10.1103/PhysRevB.65.045207