Interaction of discrete breathers with thermal fluctuations

Abstract

Discrete breathers (DB) are time-periodic and spatially localized lattice excitations, which can be linearly stable or unstable with respect to either localized or extended perturbations. We analyze the interaction of DBs with a thermalized background of small amplitude lattice excitations in a one-dimensional lattice of Morse oscillators with nearest neighbour interaction. We find that stable DBs are barely influenced by the thermal noise. Unstable DBs are starting to propagate through the lattice, without loosing their localization character. The instability can be both due to localized perturbations, as well as due to extended perturbations. We discuss these observations in terms of resonances of DBs with localized and delocalized perturbations, and relate them to the issue of DB impact on statistical properties of nonlinear lattices.

Gap discrete breathers in 2D and 3D crystals

“…В работах [31][32][33] исследовалась возможность суще-ствования ДБ в двумерной модели кристалла в услови-ях термодинамического равновесия при конечной тем-пературе с использованием упрощенных межатомных взаимодействий. Было показано, что в решетках, допу-скающих существование ДБ, растет время жизни высо-коэнергетических атомов [31][32][33].…”

“…Было показано, что в решетках, допу-скающих существование ДБ, растет время жизни высо-коэнергетических атомов [31][32][33].…”

Graphane -- material for hydrogen storage, breathers and kinks

“…Note that an atom can be absorbed on the surface (chemical process) or adsorbed on the surface (physical process). DBs can be spontaneously excited at a finite-temperature thermal equilibrium [102] - [105]. The maximum kinetic energy of the externally excited DBs is found [38] to be very close to the energy barrier for hydrogen desorption.…”