Current relaxation in nonlinear random media.
We study the current relaxation of a wave packet in a nonlinear random sample coupled to the continuum and show that the survival probability decays as P(t) approximately 1/t(alpha). For intermediate times t<t(*), the exponent alpha satisfies a scaling law alpha=f(Lambda=chi/l(infinity)), where chi is the nonlinearity strength and l(infinity) is the localization length of the corresponding random system with chi=0. For t>>t(*) and chi>chi(cr) we find a universal decay with alpha=2/3 which is a signature of the nonlinearity-induced delocalization. Experimental evidence should be observable in coupled nonlinear optical waveguides.
Kottos
Tsampikos
T
Max-Planck-Institut für Strömungsforschung, Bunsenstrasse 10, D-37073 Göttingen, Germany.
Weiss
Matthias
M