Use Finite-difference Time-domain Methods To Study On Characteristics Of Plasma Photonic Crystals

The plasma photonic crystals (PPCs) are artificially periodic array composed of alternating the plasmas and dielectric materials. As we known, the unmagnetized plasma is a kind of dispersive and dissipative medium. On the one hand, the refractive index of unmagnetized plasma that is determined by incident electromagnetic wave frequency and plasma frequency is less than 1, Even it is negative. On the other hand, when the frequency of incident electromagnetic wave is higher than plasma frequency, collisional plasma can efficiently absorb electromagnetic waves, thereby transferring energy from the incident electromagnetic wave to the internal energy of plasma. But the magnetized plasma is more complex than unmagnetized plasma, the magnetized plasma can be characterized by anisotropy , dispersion and dissipation at the same time. When incident electromagnetic wave propagate through the magnetized plasma, the pass band and the forbidden band will be gotten. Therefore, the characteristics of the plasma make the plasma photonic crystals obtain many new particular characteristics comparing with conventional photonic crystals.In this paper, the incident electromagnetic wave propagation through the plasma photonic crystals is simulated. Using the Gaussian pulse as driving source, the electric field component which be gotten in the time-domain be transferred to the frequency-domain by using Fourier transform, then the transmission coefficients through the plasma photonic crystals are computed. The characteristics of forbidden band will be used to describe the plasma photonic crystals by transmission coefficients magnitude versus frequency. The main content as follow:1 .Current density convolution (JEC) on finite-difference time-domain (FDTD) method of the unmagnetized plasma is applied to discuss the characteristics of periodic forbidden band of one dimension unmagnetized plasma photonic crystals; Under the isothermal hypothesis, a deduced finite-difference time-domain (FDTD) algorithm is applied to study the characteristics of its forbidden band effected by the plasma temperature , density and rising time; The piecewise linear current density recursive convolution(PLCDRC) on finite-difference time-domain (FDTD) algorithm of the unmagnetized plasma is applied to discuss the one dimension unmagnetized plasma photonic crystals with a defect layer and analyze the effect on defect mode properties of unmagnetized photonic crystals2.The piecewise linear current density recursive convolution(PLCDRC) on finite-difference time-domain (FDTD) method of the magnetized plasma is applied to discuss the characteristics of periodic forbidden band of one dimension magnetized plasma photonic crystals; study the characteristics of its forbidden band effected by the effects of plasma temperature , density and rising time; discuss the one dimension magnetized plasma photonic crystals with a defect layer and analyze the effect on defect mode properties of magnetized photonic crystalsThe results are showed that we can get different characteristics of defect modes and forbidden band of one dimension plasma photonic crystals by changing parameters of plasma, periodic structures parameters of plasma photonic crystals and plasma temperature , density , rising time.