4*4 transfer-matrix method for defect mode splitting in magnetic photonic crystal

Using the 4*4 transfer-matrix method go through the transmittance formula of one dimensional magnetic photonic crystal with and without external magnetic fields, respectively. Numerical simulation results show that defect-mode splitting critically depend on the magneto-optical gyrotropy factor and defect mode in right-hand and left-hand circularly polarized move toward lower and higher frequency in the present of a magnetic field, respectively. Our results prove out the fact that the defect mode splits into two modes under the external magnetic fields and with the increase of the magnetic field strength the two peaks separate to both sides. Considering the dispersion of the light, we get the same conclusion, which present an effective way to new type of tunable filters.