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The polarization control of silicon photonic integrated devices is an urgent problem caused by the birefringence effect due to the structural asymmetry of the silicon (Si) waveguide (450 nm × 220 nm), which results in polarization loss, polarization mode dispersion, and wavelength polarization related issues. This work presents a proposal for a compact silicon hybrid plasmonic waveguide (HPW) polarization controller. The proposed design includes two sets of Bragg gratings, placed within different material layers of the polarization controller. By changing the relative positions of the two sets of Bragg gratings, the absorption problem generated by the hybridized modes can be reduced or even eliminated, thus the reflection spectrums of the TE and TM polarization mode are optimized. Besides, one polarization mode of TE mode and TM mode has a high reflectivity, while the other polarization mode has a high transmission by designing different grating periods and other parameters. Based on the simulations and design, the silicon HPW polarization controller has an optimal length of 23.247 microns when used as a TM-mode polarization reflector, and the corresponding optimal length is 19.694 microns when used as a TE-mode polarization reflector. At the working wavelength, the polarization extinction ratio (ER) and insertion loss (IL) of the TM-mode polarization reflector are greater than 28.1 dB and less than 0.087 dB, respectively, and the ER and IL of the TE-mode polarization reflector are greater than 18.9 dB and less than 0.085 dB, respectively. Compared with conventional silicon waveguide polarization controllers, TE mode and TM mode separation, selection, transmission, and reflection of the proposed silicon HPW polarization controller can be achieved with a compact size. In the future, will be potential for widespread applications for this technology in both silicon photonic devices and silicon photonic integrated circuits.
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