Application Research Of Single-Core Photonic Crystal Fiber

Photonic crystal fiber(PCF) has many unique properties that the traditional fiber do not has, with the mature of theory of PCFs, and the development of manufacturing of PCFs, large numbers of novel kinds of PCFs come out. In the transmission of information, PCF has been more and more used to realize miniaturization of the system. So, PCFs has important significance for integrated optics.This paper primarily researches on single-core PCF, a single-core PCF polarization splitter is proposed. The full- vector finite element method(FEM) and the semi- vector beam propagation method(BPM) are employed to numerical simulation and theoretical analysis of high birefringence PCF characteristics. Besides, an M-Z sensor based on PCF and SMF has been made. For improving its temperature sensitivity, ethanol is filled into the air-holes. Measuring the temperature and the refractive index variables with the sensor. The main content is: 1. The classification and characteristics of PCF are briefly introduced. The research background and the present situation of PCF are summarized. 2. Several theoretical study of PCF is briefly introduced. Focus on introducing t he basic principles, the boundary conditions, the COMSO L Multi-physics simulation software and the use of software simulation steps of the full- vector FEM. The basic principle and the boundary conditions of the semi- vector BPM are also introduced. 3. A kind of single-core PCF splitter based on tellurite glass is proposed. Full vector finite element method is used to analysis its characteristics. The simulation results show this kind of splitter can split light in the bands of 1.3 and 1.55μm, propagate along the orthogonal polarized directions. For a propagation distance of 15 mm, the-20 d Bbandwidth of crosstalk in 1.3 and 1.55μm bands, reach 44.2 and 67.1nm, respectively.4. A novel kind of M-Z interferometer is fabricated, through core-offset splicing PCF withSMFs, the sensing unit is made to sensing the temperature and refractive index variables.When variable of refractive index changes 0.05, the dip shift from 1578.1nm to1583.2nm, in other words, the dip has red shift; the refractive index sensitivity is102nm/RIU. PCF has stability of temperature, when the temperature varies from 75℃ to25℃, the dip shifts from 1578 nm to 1578.4nm, the sensitivity is-3-8′10 nm/℃. 5. For the M-Z interferometer which is fabricated in chapter 4, in order to change theinsensitivity of it, ethanol is filled into the air- holes, for the large thermal coefficient ofethanol, the sensor has large sensitivity for temperature. When the temperature changesfrom 75℃ to 25℃, dip shifts from 1525.7nm to 1576.1nm, the sensitivityis -1.008 nm/℃. When refractive index changes 0.05, dip shift from 1551.3nm to1555.4nm, the refractive index sensitivity is 80.3nm/RIU.