Omnidirectional narrow-band ultraviolet filtering based on one-dimensional defective photonic crystal containing hyperbolic metamaterial

As a kind of Fabry-Perot cavities, one-dimensional photonic crystals (1DPCs) with defect layers have been widely utilized for narrow-band filtering. However, according to the Bragg interference condition, photonic band gaps (PBGs) in conventional all-dielectric 1DPCs shift towards shorter wavelengths (blueshift) as the incident angle increases. Therefore, transmittance peaks in all-dielectric one-dimensional defective PCs also shift along with PBGs as the incident angle increases. Recently, the emergence of angle-insensitive PBGs in 1DPCs containing hyperbolic metamaterials (HMMs) provides us a possibility to realize omnidirectional narrow-band filtering. In this paper, we design an angle-insensitive ultraviolet PBG in a 1DPC containing HMM, where HMM layer is mimicked by a subwavelength dielectric-metal multilayer. By introducing a defect layer into the 1DPC and adjusting the dielectric thickness within the 1DPC, we achieve omnidirectional narrow-band ultraviolet filtering with angle-insensitive property. This omnidirectional narrow-band filtering might possess applications in digital display, organic solar cell and wavelength division demultiplexing.