Omnidirectional surface guided modes from one-dimensional photonic crystal formed by single-negative materials

We employ the transfer matrix method (TMM) to investigate the guided modes in an air-core layer, which is sandwiched by the one-dimensional photonic crystal with alternate single-negative materials. To one's interest, there exists a new kind of omnidirectional surface guided modes around two frequencies. Within the framework of effective medium approximation (EMA), the two frequencies are found to correspond to the zero-average-volume-permittivity frequency and the zero-average-volume-permeability frequency, respectively. In addition, we predict that both the symmetric (TEES,TMES)(TEES,TMES) and antisymmetric guided modes (TEOS,TMOS)(TEOS,TMOS) can be supported in the system.