We study moving topological solitons (kinks and antikinks) in the nonlinear Klein-Gordon chain. These solitons are shown to exist with both monotonic (non-oscillating) and oscillating asymptotics (tails). Using the pseudo-spectral method, the (anti)kink solutions with oscillating background (so-called nanopterons) are found as travelling waves of permanent profile propagating with constant velocity. Each of these solutions may be considered as a bound state of an (anti)kink with a background nonlinear periodic wave, so that the wave "pushes" the (anti)kink over the Peierls-Nabarro barrier. The stability of these bound states is confirmed numerically. Travelling-wave solutions of permanent profile are shown to exist depending on the convexity of the on-site (substrate) potential. The set of velocities at which the (anti)kinks with monotonic asymptotics propagate freely is calculated. We also find moving non-oscillating (anti)kink profiles with higher topological charges, each of which appears to be the bound state of (anti)kinks with lower topological charge (\Q\ = 1). ©2000 Elsevier Science B.V. All rights reserved.
|Number of pages||15|
|Journal||Physica D: Nonlinear Phenomena|
|Publication status||Published - 15 Apr 2000|
- Nonlinear lattice
- Pseudo-spectral method
- Topological solitons