Terahertz polarization rotator based on silicon asymmetrical structure

Terahertz polarization control has a wide range of applications in imaging, communication, biology, and analytical chemistry. Polarization rotator is of great significance as one of the main units of a polarization controller. In this paper, we propose and simulate a terahertz polarization rotator based on silicon asymmetrical structure, whose polarization extinction ratio reaches up to 35 dB and 26 dB for transverse electronic and transverse magnetic modes, respectively. Its 15-dB bandwidth is 40 GHz for a conversion length of 4.4 mm. The results show that the integrated scheme can achieve the function of polarization rotation with high conversion efficiency. We believe it will play an important role in terahertz polarization management.