Development of micro optical polarization splitters having multi layr structure

叠层偏振分束器是一种由高折射率和低折射率的周期性叠层透明材料薄膜组成的超小型空间走离偏振器。它是构建光通信系统功能光器件的关键部件。在本文中，我们讨论了波长分别为1.55微米和1.3微米的高性能LPS的制作技术。对于波长较长的a-Si：H/SiOx：H多层膜，我们采用射频溅射的方法成功地制备了厚度大于200微米的多层膜，具有较高的光学性能和机械稳定性，并获得了适用于光学器件的低损耗薄膜。对于较短的波长，我们采用等离子体增强CVD方法制备了a-Si_x；1-x&Gt；C_x/SiO_2多层膜，通过对衬底温度和气体流量等沉积条件的研究，获得了低损耗的多晶硅薄膜。将该器件初步集成到一个用于可编程光连接的二维波导电路中，并对其基本工作进行了实验验证。我们还展示了集成到两个热膨胀芯(TEC)光纤阵列中的无透镜和无对准光隔离器。这验证并认可了将功能设备集成到TEC光纤中的原则和有用性。

A laminated polarization splitter is an ultrasmall spatial walk-off polarizer composed of periodically laminated thin films of transparent materials with a high refractive index and a low index. It is a key component to build functional optical devices for optical communication systems. In this report, we discuss the fabrication techniques of LPS's for the wavelength of 1.55 mu m and 1.3 mu m, respectively, with high performance. For the longer wavelength, we successfully deposited a-Si : H/SiOx : H multilayrs by rf sputtering method with a thickness more than 200 mu m with high optical properties and mechanical stability, and obtained low loss LPS's applicable to optical devices. For the shorter wavelength, we fabricated a-Si_<1-x>C_x/SiO_2 multilayr deposited by plasma-enhanced CVD method and obtained low loss LPS due to the study on deposition conditions such as the substrate temperature and gas flow rate. The fabricated LPS was tentatively integrated into a 2D waveguide circuit for a programable optical connect and the fundamental operation is experimentally verified. We also demonstrated lens-free and alignment-free optical isolators integrated into an array of two thermally expanded core (TEC) fibers. This verifies and endorses the Principle and usefulness of integrating functional devices into TEC fibers.