Two-dimensional complete band gaps in one-dimensional metal-dielectric periodic structures

摘要

It is widely believed that a one-dimensional (1D) periodic layered structure with ordinary materials can only have a band gap for certain propagation directions. However, we reveal that a 1D metal-dielectric periodic structure can trap transverse magnetic waves for any angle of propagation in a plane, owing to the existence of a two-dimensional (2D) complete band gap. The complete gap comes from Bragg scattering together with the cutoff effect of the metal-dielectric-metal waveguide. We discuss the criteria for the geometric and material parameters to realize a 2D complete gap and illustrate the complete band-gap effects with real structures.