Effect of the ratio of hole radius to lattice spacing on transmission characteristics for metal/dielectric photonic crystal

In this work, the effect of the ratio of hole radius to lattice spacing (r/a
0
) on transmission characteristics for the metal/dielectric photonic crystal (MDPC) is investigated. The relationship between the photonic band gap (PBG) dependent on r/a
0
is discussed. This is because the characteristics of the PBG dependent on r/a
0
affect transmission characteristics for MDPC. The plane wave method (PWM) is used to simulate the PBG by changing r/a
0
from 0.2 to 0.3. For hexagonal arrays, we find that with r/a
0
being 0.25, the desired PBG structure is achieved. The experimental study for hexagonal air holes arrays residing in the Au@SiO2@Si structure by changing r/a
0
from 0.2 to 0.3 is presented. The result shows that with r/a
0
being 0.25, a narrow bandwidth and high efficiency transmission is achieved. It is demonstrated that the distinct effect of r/a
0
on transmission characteristics for MDPC structure.