Optimization of Broadband Perfect Absorber by Weierstrass Factorization

• Main Authors: Xianshun Ming, Liqun Sun
• Format: Article
• Language: English
• Published: IEEE 2019-01-01
• Series: IEEE Photonics Journal
• Subjects: Broadband perfect absorber; nanostructure design; Weierstrass factorization.
• Online Access: https://ieeexplore.ieee.org/document/8859362/

We present a new method based on Weierstrass factorization to optimize broadband perfect absorber (BPA) made of metal-dielectric-metal elements, which is an efficient and general approximation to calculate the absorption of these subwavelength structures. With the resonant wavelengths estimated by semi-analytical equations, we design a planar BPA tiling three subunits in one unit cell and a vertical tapered BPA stacking 20 pairs of metal-dielectric layers in one unit cell. Both BPAs shows almost over 90% and wide angle absorption in the concerned range. This method can be an alternative to the traditional full vector methods in initial design.