Abstract
We offer a comparative study of the self-trapping phenomenon in square and honeycomb lattices, showing its dependence on the initial condition and lattice topology. In order to describe the dynamical behavior of one-electron wave packets, we use a discrete nonlinear Schr\"odinger equation which effectively takes into account the electron-phonon interaction in the limit of an adiabatic coupling. For narrow wave packets and strong nonlinearities, the electron distribution becomes trapped irrespective to the lattice geometry. In the opposite regime of wide wave packets and small nonlinearities, a delocalized regime takes place. There is an intermediate regime for which self-trapping is attained in the honeycomb lattice while the wave packet remains delocalized in square lattices. Further, we show that the critical nonlinear strength ${\ensuremath{\chi}}_{c}$ scales linearly with the initial wave-packet participation function $P(0)$ with the ratio ${\ensuremath{\chi}}_{c}/P(0)$ being on the order of the energy bandwidth.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
