Second-order accurate FDTD equations at dielectric interfaces for TE modes

Based on the discretization of the integral forms of Maxwell´s curl equations over finite volumes including the dielectric interface and Taylor series extending of continuing field components, we have obtained rigorous second-order accurate FDTD equations at a dielectric interface for TE modes though choosing the proper size of non-uniform Yee´s grids across the interface and tangential and normal effective permittivities in the grids containing the interface. The numerical experiments in a 2D dielectric cavity have demonstrated the accuracy of these second-order accurate FDTD equations.