Abstract
For electromagnetic, there are some perfect physical properties in the photonic crystal. It can let the particular wavelength forbid propagated to anywhere. The important thing with photonic crystal is arranging the air hole or dielectric column for the period and chooses the material to fabricate it. This excellent property has made photonic crystals useful for communication applications such like narrow-band filters, frequency-selective mirrors, and high-Q cavities. There are more and more evidences that the integration of these photonic crystals, passive and active components will be helpful to realize complex optical circuits. Due to fabrication of semiconductor and nano-scale technology, we could extent the field of optical communications especially develop a photonic crystal device. Fabricating the photonic crystal on lithium niobate wafer is a novel idea in waveguide applications. To tune the parameter of photonic crystal, there will be more applications for optical communications and can be a excellent micro optoelectric deivce.