  We report a first-principles description of the induced wake potential and
density in real solids. The linear-response formalism is used to obtain the
potential and density induced by an external charge penetrating through an
inhomogeneous periodic system. The linear dynamical response of the system is
evaluated in the random-phase approximation, by including the full band
structure of the solid. The impact of the periodic crystalline potential is
analyzed, and variations of the wake along different channels in Al and Si are
investigated.
