Trapping and transmission of matter-wave solitons in a collisionally   inhomogeneous environment
  We investigate bright matter-wave solitons in the presence of a spatially varying scattering length. It is demonstrated that, even in the absence of any external trapping potential, a soliton can be confined due to the inhomogeneous collisional interactions. Moreover we observe the enhanced transmission of matter-wave solitons through potential barriers for suitably chosen spatial variations of the scattering length. The results indicate that the manipulation of atomic interactions can become a versatile tool to control the dynamics of matter waves. 
G. Theocharis, P. Schmelcher, P. G. Kevrekidis and D. J. Frantzeskakis