  The concept of ponderomotive potential is upgraded to a regime in which
radiation friction becomes dominant. The radiation friction manifests itself in
novel features of long-term capturing of the particles released at the focus
and impenetrability of the focus from the exterior. We apply time scales
separation to the Landau-Lifshitz equation splitting the particle motion into
quivering and slow drift of a guiding center. The drift equation is deduced by
averaging over fast motion.
