A fundamental question concerning systems which are both disordered an
d nonlinear is whether or not Anderson localization is weakened by the
nonlinearity. Theory predicts that localized eigenstates will survive
nonlinearity, whereas nonlinear pulses may or may not experience the
effects of localization depending on the relative magnitude of the And
erson localization length and the characteristic width of the pulse. W
e have used nonlinear surface waves on a superfluid helium film to obt
ain results in agreement with the theoretical predictions.