Title: Intrinsic Localized modes: A mechanism for the migration of defects

Speaker: J Cuevas (slides ppt 360 kb)

Abstract: The Frenkel-Kontorova model supports discrete breathers due to the nonlinearity of the on-site potential. It provides the simplest way of modelling single or double vacancies (one or two contiguous empty wells) and interstitials (two particles in the same well). When a moving breather reaches the vacancy, the latter can move forwards, backwards or remain at rest, however, there is no correlation between the kinetic energy and the number of vacancy jumps. The observed regimes for double vacancies are: rest, breaking and forwards movement (with breaking). For interstitial, depending of the width of the coupling potential well, movement is either forwards, either backwards, forwards or rest.

Physics Department, Universidade do Algarve, Faro, Portugal, July 2005. Talk by J Cuevas