  We present a phase field crystal model for driven systems which describes
competing effects between thermally activated diffusional processes and those
driven by externally imposed ballistic events. The model demonstrates how the
mesoscopic Enrique and Bellon [Phys. Rev. Lett. 84, 2885 (2000)] model of
externally induced ballistic mixing can be incorporated into the atomistic
phase field crystal formalism. The combination of the two approaches results in
a model capable of describing the microstructural and compositional evolution
of a driven system, while incorporating elasto-plastic effects. The model is
applied to the study of grain growth in nanocrystalline materials subjected to
an external driving.
