π-kink propagation in the damped Frenkel-Kontorova model K. Alfaro-Bittner, M. G. Clerc, M. A. García-Ñustes and R. G. Rojas EPL, 119 4 (2017) 40003 Published online: 06 November 2017 DOI: 10.1209/0295-5075/119/40003