Ground state and dynamics of two coupled Peierls chains

We present a numerical study of the interchain coupling for trans-polyacetylene on the basis of the Su-Schrieffer-Heeger model. In a mean field approximation we investigate the ground state of two coupled chains and find in dependence on the coupling strength and the chain length four different phases. We derive a phase diagram for fixed chain ends and find that for realistic coupling strengths and chain lengths the matched phase is stable contrary to results obtained for infinite chains. We investigate for the first time the influence of a resonant femtosecond pulse on the mismatched two-chain system. For longitudinal electric field the results are quite similar to those for isolated chains. In the transverse case charge is transferred between the chains.