Disngn And Analysis Of Optical-Communication-Band Sub-Wabelength Gtating Polarizer

With the rapid development of high-speed optical communication system, optical computing and optical networks, more demanding requirements are imposed on the optoelectronic devices. One of new kind photonic integrated devices based on micro/nano structures has become an inevitable trend of the development of high-speed optoelectronic devices. With the rapid growth of the communication capacity, the power consumption, volume, and reliability of the network terminal and the node devices have become a serious problem, traditional optoelectronic devices due to its material, structure and process of the self-limiting factor, has been impossible to meet the demand for the development of a new generation of information technology. With the development of micro/nano technology, new type of micro/nano optoelectronic integrated devices have the advantages of small size, high reliability, functionality, will become the direction of the development of a new generation of information technology. As novel micro/nano structures, sub-wavelength gratings used in high-performance optoelectronic devices, are attracting a lot of attention. When the period of sub-wavelength are at the scale of nanometer, and employing special patterns or even asymmetric structure, new optical phenomena and physical laws will emerge. Study on sub-wavelength will contribute to the developing of high-performance optoelectronic devices and push forward the device renovation and promotion in multiple fields including high-speed optical communication and optical networks.The main contents of this paper are as following:1. Thesis briefly describes the basic methods for the diffractive optical elements. The rigorous coupled-wave analysis method is adopted to research one-dimensional rectangular sub-wavelength grating structures. The coupled-wave equation for the incident light with TE and TM polarization are obtained.2. Thesis discussed in detail on the effective medium theory of sub-wavelength grating structure, according to the Maxwell theory, derived zero level equivalent coefficient of TM polarization and TE-polarized on wavelength grating structure, analyzed the sub-wavelength grating parameters on the diffraction efficiency.3. According to the requirement of the optical communication devices, sub-wavelength grating polarizer was designed based on SOI. The grating parameters such as the period, depth, fill grove that influence the diffraction efficiency are analyzed. Calculation results display the TM mode diffraction efficiency is more than95%, and the TE mode diffraction efficiency is less than5%, the rectangle sub-wavelength polarizer grating has good performance than others shapes in the optical communication band of1550nm.4. The rectangle sub-wavelength grating polarizer was fabricated. The experimental results and theoretical simulation results almost match, in order to verify the correctness and practicality of the grating.5. The plasma enhanced chemical vapor deposition was researched, coating process, common faults and processing methods were sorted.