Magnetic field induced bandgap in two dimensional magneto-optical photonic crystals

Abstract

The photonic bandgap of magneto-optical (MO) photonic crystals (PhCs) induced by an external dc magnetic field is theoretically investigated with the plane-wave expansion method. The effect of PhC lattice shape, MO filling fraction and dc magnetic intensity on such type of bandgap has been studied. It is found that PhC with triangular lattice is superior to PhC with square lattice in term of bandgap width; thus, the one-way waveguide composed by the former PhC has a broader operation band. Moreover, there exists a certain value of external magnetic field at which the bandgap reaches a maximum. These results are found to be in agreement by finite element analysis of transmission property of one-way waveguides.