  We investigated numerically the electromagnetically induced transparency
(EIT) behavior with the maximum Q factor is up to 28000 in a metal-dielectric
metamaterial. It composed of two layers, a metallic strip as bright mode
stacked above a dielectric rod as another bright mode. The coherent coupling
between the broad electric dipole induced by the metal strip and the narrow
toroidal dipole induced by the dielectric rod leads to the destructive
interference, then introduces a transparency window. Interestingly, the EIT
window could be effectively influenced by varying parameters of the two layers
and the thickness of middle spacer. This process can be explained by using
two-particle model. Furthermore, the radiation loss is greatly suppressed
within the EIT windows and the slow light effect is improved a lot. These
excellent properties also provide an effective platform for the filters and
sensitive chemical and biological sensors in the optical range.
