Micro-cavity Design And Characteristics Research Of Photonic Crystal Based On Tunable Refractive Index

With the development of optical communication technology and optical passive devices, the tunability and application technology of photonic crystal (PC) have become a hot research issue in the photoelectric field. The properties of photonic crystals are affected by the structures or materials of medium. This thesis focuses on the optical transmission characteristics of photonic crystal micro-cavity with different structures or materials types to make the transmission properties of photonic crystal tunable. The primary content includes:On the basis of Maxwell electromagnetic field theory, light in the media as electromagnetic wave at certain frequency is considered. The physical mechanism of photonic band gap is analyzed theoretically and eigenequation of photonic crystal is deducted. Based on analysis of the mathematical calculation of RSOFT, the transmission characteristics of photonic crystal slab (PC Slab) are given.The characteristics of the band and propagation of photonic crystal micro-cavity of triangular lattice and square lattice are analyzed. Also, the influences caused by the ratio of columns or hole radius and constant lattice to band gap are study on. The optical properties of perfect and defect photonic crystals are discussed with emphasis on the influences of geometry and materials of defect on propagation properties.The tunable properties of photonic crystals are studied in the thesis. Electro-optical crystal potassium titanyl phosphate (KTiOPO4, KTP) is introduced to the design of photonic crystal micro-cavity. One and two dimensional photonic crystal micro-cavity with tunable refractive index are designed. Photon transmission characteristics are further discussed to enhance the basis of research on photonic crystal tunability. The defect cavity band gap of two-dimensional photonic crystal is analyzed with the plane wave expansion method. Photonic crystal band gaps decrease with the increase of KTP crystals refractive index, and the mid-frequency of band gap is smaller. Compared with the band gaps of square lattice and triangular lattice, band of triangular lattice changes more obviously and modulated better. Mention above, the works and results in the thesis can contribute theoretics basis to experimental production and application of the tunable photonic crystal micro-cavity.