Directed long-range transport of a nearly pure component atom clusters by the electromigration of a binary surface alloy

Assuming a vacancy-mediated diffusion, continuum model for electromigration-driven transport of an embedded atom cluster across surface terrace phase-separating A$_x$B$_{1-x}$ alloy, such as fcc AgPt(111), is presented. Computations show that the electron wind carries over hundreds lattice spacings and in set direction, while grows its purity improves during drift. Impacts current density, diffusion anisotropy, magnitude sign ratio effective charges $q_A/q_B$, jump frequencies $\Gamma_A/\Gamma_B$ on cluster's drift speed, shape are demonstrated.