On the interaction of propagating intrinsic localized modes with an isolated impurity in a linear atomic chain

• We describe interaction of intrinsic localized modes with lattice defects.
• A simple numerical approach shows different processes of energy interchange.
• Mass and force constant defect cause the same types of processes.

We study the interaction between an intrinsic localized mode and a substitutional defect in a linear chain of atoms interacting with their nearest neighbors through a translational invariant potential function with a harmonic and a quartic anharmonic terms. The classical equations of motion are solved by means of a numerical iterative procedure and moving solutions are sought. The frequencies and atomic displacements from the equilibrium positions are calculated and the interaction between the excitation and the impurity is observed through the changes of the mode profile and the frequency as the breather moves towards and through the impurity.