Dual-Ultrawideband Linear-to-Circular Converter with Double Rotation Direction in Terahertz Frequency

In this paper, we propose a linear-to-circular (LTC) converter with a simple construction in Terahertz regime. There are many superior conversion properties of the proposed converter. Firstly, this converter operates in dual-band such as 0.44-0.76 THz and 1.10-1.72 THz. Secondly, the ultrawideband conversion is achieved, e.g. the relative bandwidths are −53.3 % and $\sim$ 44 %, respectively. Third, the right-hand polarization conversion (RHPC) and left-hand polarization conversion (LHPC) are respectively realized in the operating bands. Moreover, the high-efficiency LTC conversion is obtained, i.e. the efficiencies for RHPC and LHPC are greater than 99 % and 90%, respectively.