  We use analytic theory and computer simulation to study patterns formed
during the growth of two-component assemblies in 2D and 3D. We show that these
patterns undergo a nonequilibrium phase transition, at a particular growth
rate, between mixed and demixed arrangements of component types. This finding
suggests that principles of nonequilibrium statistical mechanics can be used to
predict the outcome of multicomponent self-assembly, and suggests an
experimental route to the self-assembly of multicomponent structures of a
qualitatively defined nature.
