  Open quantum systems consisting of coupled bound and continuum states have
been studied in a variety of physical systems, particularly within the scope of
nuclear, atomic and molecular physics. In the open systems, the effects of the
continuum decay channels are accounted for by indirect non-Hermitian couplings
among the quasi-bound states. Here we explore anti-Hermitian coupling in a
plasmonic system for spatially manipulating light on the nano-scale. We show
that by utilizing the anti-Hermitian coupling, plasmonic antennas closely
packed within only {\lambda}/15 separations can be individually excited from
the far field, which are otherwise indistinguishable from each other.
