Research On Microstructure Fiber Photonic Devices Based On Birefringence Of Magnetic Fluid

As an important communication technology in the 21 st century,all-optical communication has far-reaching influence on the development of society and the progress of science.People have higher requirements for large-capacity and high-speed information transmission and processing technologies.Research on fiber-optic photonic devices with miniaturization,high performance and low loss has become a hot topic in the field of optoelectronics.Microstructured fibers are widely used in the research of new fiber photonic devices due to their structural diversity and excellent performance.In particular,the air holes inside the microstructured fiber provide the possibility of integration of various functional materials.The interaction between materials and various external environmental parameters further broadens the application range of the fiber device.Compared with traditional optical fiber devices,these devices are characterized by compact structure,high sensitivity and wide application range.In this paper,various magnetic fiber liquid filling methods are used to fill magnetic fluid into various microstructured fibers,and the light propagation characteristics are analyzed.Combined with the birefringence characteristics of the magnetic fluid,theoretical and experimental analysis was carried out to achieve high sensitivity and high resolution magnetic field sensing.The main contents of this article include:1.The research method of micro-structured fiber material filling is introduced.Through the simulation software such as Comsol based on finite element method,the fiber structure can be modeled,and the physical parameters filled with various materials can be set to realize the research on the fiber mode field after material filling;According to the difference of filling material and filling structure,several simple and easy filling methods of fiber materials are introduced in detail,and the design of the device can be realized by selecting a suitable filling method according to the actual situation.2.Using a direct filling method to fill the magnetic fluid into a silica tube that matches the size of the fiber,a highly sensitive magnetic field sensor is realized based on the birefringence characteristics of the magnetic fluid.The magnetic fluid was filled into a silica tube with a diameter of 40?m by capillary action of the liquid,and the silica tube was placed in the Sagnac loop in order to satisfy the interference of the device.Firstly,the light-passing properties of the magnetic fluid liquid core waveguide and the resonant reflecting guidance characteristics of the silica tube were studied.Then,the sensitivity of the device to the magnetic field at two concentrations was studied,and the wavelength tuning of the interference peak was realized by the external magnetic field.3.Selective filling of high birefringence photonic crystal fibers by magnetic fluid is achieved by multiple truncation methods.Filling a magnetic fluid into a large hole in the core further changes the circular symmetry of the fiber and increases the birefringence of the entire device.Based on theoretical simulation and actual experiments,the mode field distribution of the device after selective filling was studied;The magnetic fluid filling was carried out and the influence of different fiber lengths on the spectrum of the device was studied.A high sensitivity magnetic field sensor was proposed.