Electron-vibron-breather interaction

We study the interaction of breathers in the context of a coupled electron- vibron lattice system. Starting; with single-site excitations, it is demons trated that constellations exist for which the coexistence of electronic an d vibronic breathers is assured. The energy exchange between the vibrationa l and electronic subsystems and its impact on the breather formation are di scussed in detail. The coupled electron-vibron dynamics shows a tendency to ward energy redistribution into the vibronic degrees of freedom at the expe nse of the electronic energy content. Attention is paid to the relaxation d ynamics in the energy exchange and we discuss the attainment of a steady re gime for the coupled electron-vibron dynamics starting from a nonequilibriu m state. It is demonstrated that the presence of breathers has a strong imp act on the relaxation dynamics. Breathers can assist the relaxation process . With the help of a linear stability analysis, we show why the electronic subsystem acts as an energy donor while the vibron system serves as the ene rgy acceptor. To this end we investigate the existence and stability of loc alized breathing eigenmodes capable of energy trapping. A frequency analysi s reveals that strong exchange also occurs due to a temporal transition fro m single-frequency breathers to these oscillating with two frequencies and their temporal resonance interaction. Finally, the self-stabilized electron -vibron system relaxes to a combined electron-vibron breather. On increasin g the electron-vibron coupling strength, only a vibronic phonobreather of l arge amplitude survives, whereas the electronic subsystem tends to energy e quipartition.