  We analyze finite temperature effects in the generation of bright solitons in
condensates in optical lattices. We show that even in the presence of strong
phase fluctuations solitonic structures with well defined phase profile can be
created. We propose a novel family of variational functions which describe well
the properties of these solitons and account for the non-linear effects in the
band structure. We discuss also the mobility and collisions of these localized
wave packets.

Other Condensed Matter