Dual-band and dynamic regulated terahertz linear polarization converter based on graphene metasurface

In this paper, a highly efficient dual-band and dynamic regulated terahertz linear polarization converter is proposed. Based on the principle of electromagnetic (EM) wave polarization control, a periodic array metasurface composed of graphene split square ring and elliptical patches is designed to realize dual-band and high efficiency linear polarization conversion in terahertz band. The simulation results show that the polarization conversion ratio (PCR) is higher than 90% in the frequency range of 0.656–0.730 THz and 0.809–1.449 THz, and corresponding relative bandwidths are 10.7% and 56.7%, respectively. The dual-band performance is maintained within the incident angle of 50°. In addition, the dynamic regulation of dual-band terahertz linear polarization converter is obtained by modifying the Fermi level and relaxation time of graphene. The designed dual-band terahertz linear polarization converter has a broad application prospect in terahertz communication, sensing and spectrum. • The designed polarization converter is a dual-band terahertz linear polarization conversion metasurface. • The relative bandwidths of PCR greater than 90% are 10.7% and 56.7%, respectively. • PCR is dynamically regulated.