Optical angular transparency and broadband absorption based on photonic topological transition in black phosphorus/aluminum oxide hyperbolic metamaterial

Based on the photonic topological transition (PTT), transmission properties of a black phosphorus/aluminum oxide multilayered hyperbolic metamaterial (HMM) are theoretically investigated in mid-infrared region. The results demonstrate that an angular transparency window appears near point PTT, which is achieved by tailoring topology HMM’s equi-frequency surface. full width at half maximum 2.34°, and transmittance higher than 99.8% normal incidence. In addition, operating wavelength can be flexibly tuned adjusting concentration electrons. Besides, layered cascade structure with wide (1 µm) enhanced selectivity performance proposed, resolves shortcoming single working wavelength. spectral-selective behavior absorption also explained based PTT. These attractive make phosphorus-based HMM hold promise for potential applications angularly selective systems energy harvesting.