Subwavelength focusing in visible light band by a Fibonacci photonic quasi-crystal plano-concave lens

In this paper, we describe a one-dimensional photonic quasi-crystal (1D PQC) plano-concave lens. The simulation results show that there is a relationship between the focusing band and the photonic band structure: at the frequency ranging from the left edge of the second large bandgap to a certain frequency in the passband between the first large bandgap and the second large bandgap, the plano-concave lens can achieve subwavelength focusing. The influence of the change of the refractive index of material on the focusing characteristics of the lens is studied, and subwavelength focusing in the visible light band is achieved using common dielectric materials. The results are expected to provide a reference for the design and application of the 1D PQC plano-concave lenses. (C) 2018 Optical Society of America