Theory Group Seminars

Stochastic and dynamic aspects of energy localization in nonlinear lattices with constraints

by Stefano Iubini

Europe/Rome
248 (Building C, first floor)

248

Building C, first floor

Description
Sometimes it is more convenient to store excess energy in a small region of space rather than spreading it over all the available volume. This may happen when the evolution of a system is characterized by additional dynamic constraints that promote energy localization for entropic reasons. In this seminar I will discuss the role of peculiar nonlinear excitations (discrete breathers) for the localization process in networks of coupled oscillators. Particular attention will be devoted to the dynamics of a Discrete Nonlinear Schroedinger Equation which exhibits a metastable phase with a finite density of breathers and partial energy localization. Such state persists over very long (astronomical) times as a consequence of the extremely low interaction of these excitations with the surrounding background.