Band Broadening of Terahertz Photonic Crystals Circulator Using Two Symmetrical Hexagonal Aluminum Sheets

Future 6G communication systems will require wideband nonreciprocal devices in the terahertz frequency domain. A novel ultra-wideband terahertz circulator is implemented by inserting a NixZn1−xFe2O4 ferrite sphere into the Al2O3 dielectric rod-array. The operating bandwidth of the circulator is broadened to 40 GHz via the external matching method through two hexagonal aluminum sheets. The three-dimensional numerical simulation suggests that the designed circulator also has an excellent insertion loss and isolation of 49.37 dB and 0.56 dB, respectively, via the finite element method. The low loss, high isolation and ultra-wideband show that the proposed scheme provides an effective path for realizing high-performance THz devices.