  In this study, we explore the ratchet effect in graphene with artificial,
triangular scatterers from a theoretical standpoint. It is demonstrated that
the skew scattering of carriers by such coherently oriented defects results in
the ratchet effect in graphene, i.e., in a direct current under the action of
an oscillating electric field. Scattering on various types of defects
exhibiting threefold symmetry is considered in this paper: scattering on a
cluster in the shape of a solid triangle in the classical and quantum
mechanical limits, and scattering on three- point defects placed at the corners
of a triangle. The DC current is calculated for a classical range of
oscillating field frequencies.
