Transmittance filtering in one-dimensional dispersive photonic crystals and heterostructures

The transmittance properties of one-dimensional periodic photonic structures composed of four distinct dielectric materials are analyzed using the transfer matrix method. The refractive index dispersion of each material is modeled by the three-term Sellmeier equation. A tunable and enhanced photonic band structure is demonstrated, with flexibility achieved by adjusting the optical thicknesses of the constituent layers and varying the arrangement of unit cells within the structure. These systems show strong potential for use in band-stop and band-pass optical filters, suitable for integration into multifunctional photonic circuits operating across targeted frequency ranges. • Transmittance in 1D photonic crystals and heterostructures is investigated. • Material dispersion in constituent layers is modeled using the Sellmeier equation. • Analytical criteria for locating bandgap positions are derived. • A photonic design with robust bandgaps over selected frequency ranges is proposed.