  The ability to control propagation of electromagnetic guided modes lies at
the heart of integrated nanophotonics. Surface plasmon-polaritons are a class
of guided modes which can be employed in integrated optical systems. Here, we
present a theoretical design of a coherent surface plasmon absorber which can
perfectly harvest energy of coherently incident surface plasmons without
parasitic scattering into free space modes. Excitation of free space modes
which usually accompanies scattering of a surface plasmon by an interface
boundary is avoided due to specially tailored anisotropy of the absorber. The
concept of coherent SPP absorber is analyzed numerically for spatially
non-uniform and finite-size structures. We believe that our results will be
important for the development of integrated nanoplasmonic systems.
