Enhancement of magneto-optical responses in adjustable one-dimensional magnetophotonic crystals

We investigated the one-dimensional magnetophotonic crystals (1D - MPCs) created by magnetic defect layer sandwiched between dielectric photonic crystals (PCs) utilizing the 4 x 4 transfer matrix method (TMM). To simultaneously achieve high transmittance and large magneto-optical (MO) Faraday effect, we changed the repetition numbers of PCs and the thickness of defect layers. Using finite element method (FEM), we simulated the distribution of electric field in the length of structures. The efficient localization of light in the vicinity of defect layer led to MO responses enhancement and resonant transmittance inside the photonic band gap (PBG). For single cavity structure, the MO responses were enhanced for symmetric spatial configuration. By increasing the number of defect layer, the MO responses of MPCs were improved. The transmittance and Faraday rotation (FR) for MO multilayer structures having six cavities were obtained T = 0.92 and theta(F) = 44.5 degrees respectively. This is a proper case to design MO isolator applied in optical telecommunications.