We consider the propagation of solitons in media with an imprinted transverse periodic or parabolic refractive index modulation when the modulation depth fluctuates slightly along the propagation direction. We find that, under suitable spectral resonance conditions, small transverse soliton oscillations may get parametrically amplified.
Kartashov, Y.V., Vysloukh, V.A., Torner, L. Parametric amplification of random lattice soliton swinging. "Optics letters", Maig 2009, vol. 34, núm. 9, p. 1354-1356.