Study On Tunable Magnetic Photonic Crystal Filter

With the development of new information technologies such as artificial intelligence,cloud computing,and 5G,people are increasingly eager for the speed,capacity,intelligence,and efficiency of information transmission.Optical transmission network is praised by the market for its advantages of transmitting information by light,free from electromagnetic interference and so on.In the future,filter requirements need to be easy to integrate and small in size,and huge optical network data in the future.The transmission needs a filter with small size and good adaptability.Magnetron photonic crystal filter is the key device to realize dynamic wavelength assignment node in its network.It can dynamically download specific wavelength from multi-wavelength signal to local area,and promote the development of optical network to high-efficiency deployment.It is of great significance for the development of dynamic all-optical network.In this paper,a single-wavelength two-dimensional photonic crystal filter based on the combination of annular cavity and line defect is proposed.By analyzing the coupling mode,the circular cavity structure,and the influence of the radius of the dielectric column in the cavity on the filter performance,the final design is designed.The structural model of the circular cavity is derived.Finally,the performance of the FDTD module of lumerical simulation software is used to analyze its performance.The results show that the photonic crystal filter can achieve single wavelength 1525.5nm wavelength filtering.The magnetic medium is introduced into the two-dimensional photonic crystal filter,that is,the Si dielectric column is replaced by four magnetic media in the annular cavity,and a magnetic medium photonic crystal filter is newly constructed,and the structural parameters and the magnetic medium column are rationally arranged.The number of turns,using the change of the applied magnetic field,does not change the structure of the filter device,and realizes the change of the working wavelength from 1510 nm to 1550 nm.The FDTD module of lumerical simulation software is used to analyze its performance.The results show that the designed two-dimensional magnetron photonic crystal filter can realize wavelengths of 1510 nm,1515nm,1520 nm,1525nm,1530 nm,1535nm,1540 nm,1545nm and 1550 nm.Tuning filtering,the device has excellent performance,the insertion loss is basically within 0.41 dB,the device' Semi-peak bandwidth of device is less than 0.8nm,and has a high Q value.The performance of the photonic crystal filter is very good,and has application value in the development of optical transmission network.