Multichannel filtering properties of quaternary photonic crystals containing single-negative materials

One-dimensional quaternary photonic crystal (ABCD)N stacked by four kinds of single-negative materials is proposed, and the multichannel filtering properties of the structure (ABCD)N is investigated using the transfer matrix method. The result shows that a type of photonic gap named s-zero-eff gap that is similar to the zero-eff gap is found in the photonic structure. The multichannel filtering properties of the structures can be controlled by varying the period number, layer thickness, permittivity (epsilon) and permeability (mu). Moreover, the angular response of the filter is analyzed, which indicates that the bandgap of the structure is independent of the incident angle at the frequency is under 1.1 GHz. Thus it provides a new way to design tunable omnidirectional and angle-sensitive multichannel filters for the applications in optical filters based on PCs.