On Chip Polarization Beam Splitter Based on Inverse Design

Abstract

With the gradual improvement of optical interconnection technology’s requirements for high-speed broadband transmission of data, multidimensional multiplexing technology must be used to meet the application scenarios. Among them, polarization multiplexing technology has opened up a higher multiplexing dimension, and the application prospects are very broad. Polarization beam splitters have received a lot of attention as a key device in polarization multiplexing technology. The polarization multiplexer designed by traditional design methods with the help of classical theory and empirical calculation generally has deficiencies such as excessive volume and complex design, which is not conducive to large-scale integration, and the introduction of inverse design can effectively solve this problem and improve design efficiency. In this paper, the polarization beam splitter is implemented by using the inverse design, which can realize the output of the modes TE0 and TM0 in the bus waveguide from the respective regional waveguides, and the integration of TE0 and TM0 in the respective branch waveguides into the fusion transmission in the bus waveguide, with a size of only 2.4μm × 2μm. At the same time, simulation experiments show that the insertion loss of the device in the operating wavelength range of 1520nm to 1580nm is less than 1.4dB, and the crosstalk value between channels is almost negligible because the core layer of 220nm is difficult to achieve polarization rotation.