Title: Motion of discrete solitons assisted by nonlinearity management

Speaker: J Cuevas (zipped pdf 1 Mb)
with BA Malomed and PG Kevrekidis

Abstract: We demonstrate that periodic modulation of the nonlinearity coefficient in DNLS equation can facilitate the creation of traveling solitons. We predict analytically and confirm it with numerical simulations. There are several generic dynamical regimes, depending on the amplitude and frequency of the time modulation, and on initial thrust. These regimes include irregular motion, regular motion of a decaying soliton, and regular motion of a stable one. The motion may occur in both the straight and reverse directions. In the case of stable motion, long simulations do not show any visible loss of energy. Collisions between moving stable solitons are briefly investigated too. Two different outcomes are possible: elastic bounce, or bounce with mass transfer. The model can be realized experimentally in a Bose-Einstein condensate trapped in a deep optical lattice.

Solitons in Bose-Einstein condensates. Almagro, 9-12 February 2005.