Moving discrete breathers in bcc metals V, Fe and W

By means of molecular dynamics simulations it is demonstrated that moving discrete breathers (DBs) can be excited in pure bcc metals such as V, Fe and W. For each of the three metals, the following properties of the DBs are estimated: the frequency as the function of amplitude, the degree of spatial localization and the maximum propagation velocity. For the three studied metals, DB frequency lies above the phonon spectrum and increases with increasing DB amplitude. DBs in vanadium are much more spatially localized and robust than in iron and tungsten. Application of the presented results to the DB-induced mechanism of the void ordering under irradiation is discussed. (C) 2014 Published by Elsevier B.V.