  We perform molecular dynamics simulations to characterize the occurrence of
inhomogeneous shear flows in soft jammed materials. We use rough walls to
impose a simple shear flow and study the athermal motion of jammed assemblies
of soft particles, both for purely repulsive interactions and in the presence
of an additional short-range attraction of varying strength. In steady state,
pronounced flow inhomogeneities emerge for all systems when the shear rate
becomes small. Deviations from linear flow are stronger in magnitude and become
very long-lived when the strength of the attraction increases, but differ from
permanent shear-bands. Flow inhomogeneities occur in a stress window bounded by
the dynamic and static yield stress values. Attractive forces enhance the flow
heterogeneities because they accelerate stress relaxation, thus effectively
moving the system closer to the yield stress regime where inhomogeneities are
most pronounced. The present scenario for understanding the effect of particle
adhesion on shear localization, which is based on detailed molecular dynamics
simulations with realistic particle interactions, differs qualitatively from
previous qualitative explanations and ad-hoc theoretical modelling.
