Transmission properties of light through a metallic nanoslit with a defected horizontal nanocavity

Transmission properties of light through a vertical nanoslit milled in a metal film with a defected horizontal nanocavity by introducing a groove-cut nanostrip nearby are investigated. It is observed that the transmittance can be substantially changed in a large range when adjusting the depth of the groove or its position cut in the horizontal nanocavity. Moreover, the variations of the transmittance are given according to different matchings among the magnetic fields at the entrance of the isolated groove, at the entrance of the isolated vertical nanoslit, and at the join position of the horizontal nanocavity to the groove. The obtained results are analyzed physically in detail.