Modal properties of surface and leaky waves on metamaterial grounded slabs

In this paper some recent results concerning guidance and radiation phenomena in a double-negative (DNG) metamaterial grounded slab are presented. The dispersion behavior of TM and TE modes supported by this structure is studied and conditions have been derived which ensure the suppression of surface waves in certain frequency ranges. Particular attention has been devoted to the excitation of such structure by means of dipole ources. With reference to leaky modes, it has been shown that proper leaky modes are responsible for backward radiation from DNG slabs, and that frequency scan of the radiated beam may be achieved by properly choosing the physical and geometrical parameters of the structure.