Frequency dispersion of the polarization properties of chiral structure in the millimeter waveband

The experimental model of the gyrotropic medium for the millimeter wavelength band is designed on the bulk metamaterial - an array of flat chiral rosette-shaped structures. It is shown that the bulk metamaterial under study can rotate the polarization plane of the transmitted wave at quite large angles. Experimentally observed and investigated the region of maximum frequency dispersion of the rotation angle of the incident wave with the plane polarization. It was found that when rotation angle is closely to 90°, the level of the cross-polarization signal does not exceed -8 dB. The chirality parameters for the structures with several values of the length have been calculated. The possibility to control the position of area of the maximal frequency dispersion for polarization plane rotation angle by varying the structure length is demonstrated.