Metallic wire-grid polarizers (WGP) transmit TM-polarized light (transverse magnetic) and reflect TE polarization
(transverse electric) efficiently. They are compact, planar and compatible with integrated circuit (IC) fabrication, which
simplifies their use as optical components in nanophotonic, fiber optic, display, and detector devices. In this work, Al bi-layer
WGPs were designed and numerically simulated using finite element methods. Optical properties of the polarizers
were analyzed in the deep-ultraviolet (DUV) to infrared (IR) regions. It was observed that Al bi-layer WGPs show
broadband and high TM transmission and extinction ratio. A comparison of the performances of single and bi-layer
WGPs show that the latter is highly advantageous over the former one. An extensive study of the dependence of the
optical properties of single and bi-layer WGPs on structural parameters, such as period, metal thickness, and, duty cycle
(DC), is provided. Optimal structural parameters are obtained within the feasible parameters in terms of nanofabrication.
An Al bi-layer polarizer with a period of 80 nm and a metal layer thickness of 40 nm showed transmission up to 80%
and extinction of 40 dB (104) and broadband polarizing behavior down to a wavelength of 250 nm.