A discrete $\phi^4$ system without a Peierls - Nabarro barrier
A discrete $\phi^4$ system without a Peierls - Nabarro barrier
A discrete system is proposed which preserves the topological lower bound on the kink energy. Existence of static kink solutions saturating this lower bound and occupying any position relative to the lattice is proved. Consequently, kinks of the model experience no Peierls - Nabarro barrier, and can move freely through …