Quantum correction to solitary wave propagation in quasihyphen;onehyphen;dimensional systems: Nonadiabatic theory of soliton damping

摘要

The coupled electronndash;phonon dynamics of a onehyphen;dimensional system, which is described by a Sundash;Schriefferndash;Heeger(SSH)hyphen;type Hamiltonian, is investigated by means of a timehyphen;dependent projection operator technique. The equations of motion for the vibrational and electronic expectation values are derived without using the adiabatic and continuum approximation. When solving these transport equations numerically a quantum correction to the usual soliton solutions which we calculate from the Heisenberg equations for the SSH Hamiltonian is obtained. It turns out that the soliton solutions become unstable when the extension of the soliton is of the order of a lattice constant.