Transmission polarization converter based on V-shaped metasurface in terahertz region

Metasurfaces have attracted extensive attention due to their powerful functions, especially the manipulation of polarization state electromagnetic wave in many different areas, which aroused a lot research interest. In this work, broadband transmission converter based on V-shaped element array terahertz band is designed and analyzed, consists grating-V-shaped metasurface-grating. The top layer bottom form pair crossed gratings, middle metasurface, layers are separated by polyimide. structure parameters optimized CST microwave studio, changes can result narrow or low transmission. Cross-polarization rate conversion reach more than 80% 99%, respectively, frequency range from 0.35 THz 1.11 THz. By studying electric field distribution substrate under metasurface , it found that real part cross-polarization between adjacent metasurfaces presents similar values THz, resulting high However, opposite values, at 1.40 At same time, responses single bi-layer grating placed behind vertically incident x-polarized waves investigated results show single-layer convert linearly polarized light into light, however, structure, Fabry-Perot cavity formed grating, cross increases. This indicates provides capability conversion, existence makes F-P inside create conditions for back forth reflection waves. combined action orthogonal rate.