Enhanced mobility of high-frequency discrete breathers in a monatomic chain with odd anharmonicity

Abstract

The mobility of high-frequency discrete breathers in monatomic chains with nonlinear interatomic potentials of the nearest neighbours is considered. It was found that the odd (cubic and fifth) anharmonicity strongly affects the mobility of breathers, sharply increasing the distance that it propagates without being trapped. It was also found that the correctly chosen fifth anharmonicity leads to an inversion of stability between the bond-centred and site-centers breathers and to the low-radiative propagation of discrete breathers along the chain.