Complex-Envelope ADE-LOD-FDTD for Band Gap Analysis of Plasma Photonic Crystals

In this paper, a complex-envelope (CE) scheme is introduced into the locally one-dimensional finite-difference time-domain (LOD-FDTD) method for the band-gap analysis of the plasma photonic crystal (PPC). The un-magnetized plasma, characterized by a complex frequency-dependent permittivity, is expressed by the Drude model and solved with a generalized auxiliary differential equation (ADE) technique. The CE scheme is also applied to the perfectly matched layer. Numerical examples show that the proposed CE-ADELOD- FDTD method provides much more accurate results than the traditional ADE-LOD-FDTD with the same CFL number. The reflection and transmission coefficients of the PPC are calculated and their dependence on the relative permittivity of dielectric, the plasma frequency, the collision frequency and the plasma layer thickness is studied. The results show that the photonic band gaps of the PPC could be tuned by adjusting the parameters.