Study Of The New Y-branch Waveguide Structure And Its Functional Elements

Y branch waveguide is a kind of important single component in integrated photonic devices, which has a wide range of applications, such as waveguide interferometer modulator, ADC, optical switch, optical power splitter and so on. The power splitter based on Y structure is an important device in integrated optics, in which optical power can be distributed to two or more devices in specific ratio.The optical power splitter can be generally made from organic polymer materials. Due to the characteristics of organic polymer materials, the researches and developments of the waveguide components and integrated photonic devices which are made from polymer materials attract people's great interest in recent years.The theoretical derivation of FD-BPM is introduced based on the waveguide theory. Then the single mode condition of organic polymer ridge waveguide is analyzed. It can be achieved by selecting proper ridge width, thickness of inner ridge and outer ridge. It is calculated that when the ridge width is6μm, thickness of inner ridge and outer ridge are 3μm and 2.5μm respectively, the single-mode transmission conditions of TM mode and TE-mode are met.Based on the principle of total internal reflection, the novel symmetric and asymmetric Y branch structures are proposed, which are simulated to optimize the structure parameters. Through shifting the center axe between the input waveguide and the two branch waveguides or adjusting the deflexion angles of the two branch waveguides the asymmetric Y branch waveguide is designed. Using the former method, the asymmetric Y branch structure can achieve arbitrary splitting ratio and using the latter method, the asymmetric Y branch structure has advantages of low power loss and good fabrication tolerance.The 1×N optical power splitter which consist of symmetric and asymmetric Y-branch are proposed. The 1×4 splitter is simulated to optimize the parameters, and the simulated results show that power uniformity of the splitter is less than 0.45 dB.According to structure parameters optimized before, 1×2 and 1×4 power splitters is produced in the laboratory. To test the optical characteristics of the waveguides, a testing platform is built and the testing data are analyzed. The optical characteristics of the waveguides are consistent with the simulation and analysis according to the data.