Research on polarization beam splitter based on metamaterial subwavelength structure

Abstract

Abstract Functional devices based on metamaterials have received increasing attention in recent years due to their ability to make optical devices ultra-compact and densely integrated. To address the problems of polarisation-related losses and excessive size in polarisation beam splitters (PBS), and improve its efficiency, a new PBS based on metamaterial subwavelength structure is proposed in this paper. It achieves an ultra-compact coupling region of 1.9 × 8.2 µm2, which can effectively restrain TE polarization coupling and increase TM polarization coupling. The numerical analysis results show that both TE and TM polarizations have an insertion loss of < 0.5 dB and an extinction ratio of > 20 dB within a bandwidth of 65 nm, covering the entire C-band. At 1550 nm, the extinction ratio of TM polarization is as high as 41 dB. Realize a small footprint, short coupling length, and high-efficiency PBS.