Complete photonic band gaps and tunable self-collimation in the two-dimensional plasma photonic crystals with a new structure

Abstract

In this paper, the properties of complete photonic band gaps (CPBGs) and tunable self-collimation in two-dimensional plasma photonic crystals (2D PPCs) with a new structure in square lattices, whose dielectric fillers (GaAs) are inserted into homogeneous and nomagnetized plasma background are theoretically investigated by a modified plane wave expansion (PWE) method with a novel technique. The novel PWE method can be utilized to compute the dispersion curves of 2D PPCs with arbitrary-shaped cross section in any lattices. As a comparison, CPBGs of PPCs for four different configurations are numerically calculated. The computed results show that the proposed design has the advantages of achieving the larger CPBGs compared to the other three configurations. The influences of geometric parameters of filled unit cell and plasma frequency on the properties of CPBGs are studied in detail. The calculated results demonstrate that CPBGs of the proposed 2D PPCs can be easily engineered by changing those parameters, and the larger CPBGs also can be obtained by optimization. The self-collimation in such 2D PPCs also is discussed in theory under TM wave. The theoretical simulations reveal that the self-collimation phenomena can be found in the TM bands, and both the frequency range of self-collimation and the equifrequency surface contours can be tuned by the parameters as mentioned above. It means that the frequency range and direction of electromagnetic wave can be manipulated by designing, as it propagates in the proposed PPCs without diffraction. Those results can hold promise for designing the tunable applications based on the proposed PPCs.

Analyzing the photonic band gaps in two-dimensional plasma photonic crystals with fractal Sierpinski gasket structure based on the Monte Carlo method

“…Those results are consistent with the conclusions in Ref. 41. With increasing n means the different sizes of dielectric cylinders are inserted into the 2D PPCs, and Bragg scattering will be enhanced.…”

“…40 However, the shapes of fillers are irregular-shaped, κ(G ∥ ) has to be calculated by the numerical method. 41 As shown in Fig. 1, κ(G ∥ ) for the PPCs with Sierpinski gasket structure also can be computed by PWE method as Monte Carlo method is introduced.…”

“…Note that, the conventional PWE method cannot compute the band structures of PCs with arbitrary-shaped fillers directly. Recently, Zhang et al 41 proposed a novel PWE method to solve this problem with a meshed grid technique. However, if such a technique is used to calculate the band structures of PPCs with fractal Sierpinski gasket structure, the huge storage space and computing time have to be consumed.…”

“…1, κ(G ∥ ) for the PPCs with Sierpinski gasket structure also can be computed by PWE method as Monte Carlo method is introduced. 40,41 It is well know that κ(G ∥ ) can be written as…”

“…In order to validate the efficiency and convergence of such method, we will use a numerical example to describe them, which appears in Ref. 41. In the numerical example, the 2D PPCs are composed of the homogeneous and isotropic dielectric cylinders inserted into plasma background with square lattices under transverse magnetic (TM) wave.…”