The Design Of Tunable Filter Based On Photonic Crystals

As a new type of optical materials, photonic crystals(PCs) is a kind of micro-structure in space periodically arranged dielectric constant materials. PCs is known as optical semiconductors due to the existence of band structure. Meanwhile, due to its two iconic characters, photonic band-gap and photonic localization, photonic crystals can realize the modulation of electromagnetic waves and filtering capabilities. Through the introduction of artificial defects, breaking the cycle of its original lattice structures; you can achieve some desired objectives. If this article applies to a narrow band filtering characteristics, its function as a' filter'. Now with the significant increase in the level of preparation, the photonic crystal waveguide(PCWG), photonic crystal cavity(PCC) and photonic crystal fiber(PCF) have been widely used in the field of optical information processing. Meanwhile, because of its high sensitivity, low dissipation, and quick response and so on, PCs gains a foothold in the field of bio-sensing. In recent years, the tunable optical materials have been widely concerned and researched. Some materials with nanoscale small size and easy-integration and wide application are very popular with the scientific research workers. Based on the above basis, this paper, based on Gallium Arsenide( GaAS) spectral properties of two-dimensional photonic crystal filters, which are analyzed and studied, researched the possibility of its application in the field of bio sensing.Firstly, it introduces the basic concepts of photonic crystal, the main characteristics of photonic crystal are analyzed, and the preparation method is investigated.Secondly, on the basis of Maxwell's equations, the dispersion and group velocity, two common methods of analysis and calculation of photonic crystal is studied.Thirdly, this paper calculated the spectral properties of the two-dimensional GaAs photonic crystal filter under the situation of two kinds of defect modes, the physical properties of Photonic Crystals have been interpreted much better.Lastly, on the basis of the concept of tunable, two kinds of tuning methods of photonic crystal waveguide structure were investigated, the feasibility of these methods that be applied to the field of biosensors were explored.