以二元Fibonacci准周期结构的一维等离子体光子晶体为对象,在系统研究不同初始序列及周期数的该结构光子晶体带隙特性的基础上,给出了一种新颖的一维等离子体光子晶体结构,用于扩大全方位光子带隙.相比文献中的结构,该结构更简单(层数大大减少,且属于二元结构),全方位光子带隙宽度也更宽.此外,讨论了等离子体材料参数,如等离子厚度、等离子体频率、碰撞频率对该结构全方位带隙的影响,并与文献结构情况进行了对比.研究结果可为新型全方位反射器的设计提供重要的理论指导.
The binary one-dimensional plasma photonic crystal(1DPPC) based on Fibonacci quasiperiodic structure is studied systematically in this paper.We consider the two simplest cases.In one case,the initial sequences F0 and F1are both of single layer structure.In another case,one initial sequence(F0or F1) is of a single layer structure,while the other one(F1or F0) is of a double layer structure.Thus there are ten different kinds of initial sequences in total.The photonic bandgap characteristics of the 1DPPC with these different initial sequences and numbers of period are analyzed.On these bases,a novel structure of one-dimensional plasma photonic crystal(F3)^3with initial sequence of F0= AP,F1= P and F0= PA,F1= P is proposed in this paper to enlarge the omnidirectional photonic bandgap(OPBG).Compared with previously reported structures in the literature,this structure is simple in configuration with fewer layers and materials,and its OPBG width is wide.The influences of the parameters of the plasma material,such as the thickness,plasma frequency and collision frequency,on the OPBG characteristics of this structure are also discussed.The OPBG width increases with the increase of the thickness and plasma frequency of the plasma layer.Compared with the structures in the literature,the change of OPBG width is the fastest for the proposed structure when the parameters are relatively small.And with the same parameters,the OPBG width for the proposed structure is the widest when the parameters are greater than a certain value.The plasma collision frequency has no effect on the OPBG width for all the structures.But the OPBG width for the proposed structure is the widest when this parameter has the same value.The reason why the proposed structure has an optimal OPBG width is explained by analyzing the dispersion properties of the plasma.The real and imaginary part of the dielectric constant of plasma change with frequency significantly only in the low frequency region.Since the imaginary part of dielectric co