Defect modes and transmission properties of left-handed bandgap structures

Transmission properties of electromagnetic waves through a one-dimensional periodic stack created by alternating slabs of two types of materials, with positive and negative refractive indices were investigated. The bandgap spectrum of an infinite one-dimensional structure with and without structural defects was calculated using realistic parameters of the metamaterial derived from the microscopic approach. The properties of the defect modes in a finite number of layers with a structural defect were analyzed. The results show that the excitation of defect modes can enhance substantially the wave transmission through the structure, however, the excitation of the defect modes in the novel bandgap is characterized by relatively large relaxation time.