  Interchain hopping of solitons and polarons in polyacetylene is studied by
numerical simulation of their motion under an electric field. Use is made of
the Su-Schrieffer-Heeger model supplemented with intrachain electron-electron
interactions and dopant potentials. We find that charged solitons can hop to
the opposite chain by forming bound pairs (bipolarons). For the case of
polarons also, hopping in a pair is more favorable than single polaron hopping.
Interchain hopping of a polaron pair is more efficient than that of a soliton
pair.
