INVESTIGATION OF EFFECTIVE PLASMA FREQUENCIES IN ONE-DIMENSIONAL PLASMA PHOTONIC CRYSTALS

In this work, a detailed investigation on the effective plasma frequency fp,eff for one-dimensional binary and ternary plasma-dielectric photonic crystals is made. We extract and then analyze the effective plasma frequency from the calculated photonic band structures at distinct conditions. In the binary photonic crystal, it is found that fp,eff in a photonic crystal is usually smaller than the plasma frequency fp of a bulk plasma system. fp,eff will increase when the electron concentration in the plasma layer increases. It also increases as the thickness of the plasma layer increases, but decreases with the increase in the thickness of dielectric layer. In the ternary photonic crystal, fp,eff is shown to be decreased compared to that of in the binary one. Our results are compared with the analytical expression for fp,eff derived from the concept of effective medium. Fairly good consistence has been obtained for both results. Additionally, a discussion on the effect of loss on fp,eff is also given. The study is limited to the case of normal incidence.