  In this work we investigate quantum interference in a four-level atom coupled
to a negative index meta-material (NIMM) anisotropic plasmonic environment that
supports both TE and TM polarized surface plasmons (SP). The analysis confirms
the creation of the anisotropic environment and two dipoles can interfere with
each other even if they are orthogonal by sharing such SP modes. The
NIMM/plasmonic environment provides more options to control SP interaction with
emitters and their spontaneous emission decays and spectrum. The spectrum
depends critically on structure parameters, mode frequency, frequency dependent
electric permittivity and magnetic permeability, and the location of the atom
etc. We observe orders of magnitudes enhancement in the plasmonic-modified
decays and spectrum compared to free space case.
