The dynamics of Fermi resonance solitary waves propagating along two parallel interfaces in a layered organic semiconductor system is investigated both analytically and numerically. It is shown that the interaction between solitary waves leads to their attraction or repulsion, depending on their initial phase difference. In the case of attraction the solitary waves create a bound state, and their centers oscillate in time with respect to their common mass center. The corresponding period of oscillations is calculated. It is found that the amplitudes and widths of the solitary waves also oscillate in time.

• Received 19 February 1997

DOI:https://doi.org/10.1103/PhysRevB.57.2461