A high-performance aluminum wire-grid polarizer for the optical telecommunication applications

In this study, we propose a high-performance polarizer with Aluminum wire-grid structure that an antireflection layer (AR) is deposited between the metal wires and the transparent substrate. The polarization properties of the polarizer are analyzed in detail using rigorous coupled wave analysis (RCWA). The theoretical research shows that aluminum wire-grid polarizer has high transmission coefficient and extinction ratio in near infrared, as well as uniform performance with wide variations in the angle of incidence. For the fiber communication window of 1550nm, the transmittance and the extinction ratio are 95.4% and 35.3dB, respectively. Furthermore, a layer of Al₂0₃ forms rapidly on the aluminum wires even in high vacuum, the effect of the metal oxide layers on the polarization properties is modeled and analyzed. The results have shown that the polarizer with oxide layers coating on the wires still provides high performance. These features with their small form factor make it has potential for use in many integrated optical applications.