光子晶體光纖是以纖芯為中心，折射率在橫切面呈二維週期性排列的光子晶體結構。這種新型光纖有兩種傳播機制：全反射導向和光子能隙導向。文章中，使用平波面展開法和有限元素法分析光子晶體光纖和液晶光子晶體光纖的光學性質。
本文破壞光纖結構對稱性，提高了80%的雙折射性。以及，由此設計出高雙折射性光子晶體光纖感測器。可以發展成單頻光和動態量測。
液晶是一種能被電場和熱場控制的材料，含液晶的光子晶體光纖被稱為液晶光子晶體光纖。本文中，主要探討全反射導向和光子能隙導向的液晶光子晶體光纖，當向列型液晶光軸在不同方向時的雙折射性和色散性。以及，討論到液晶的非等向性對光子晶體光纖的影響。
當縱向非等向性時，雙折射性為零，其中，若為正單光軸材料時，非等向性越大，零色散點往低頻移動，若為負單光軸材料時，零色散點受影響不大。當橫向非等向性時，雙折射性不為零，零色散點受影響不大，不過，能量可能從另一方向的能隙缺口上損失。
最後，提出了雙導向性光纖，是一種在兩個偏振態上擁有不同傳播機制的光纖。根據雙導向性的特，我們設計了光開關和光偏振感測器。本文會在液晶光子晶體光纖在光電元件和光纖感測器等應用層面上造成深遠的影響。

Photonic crystal fibers (PCFs) are photonic crystal modes consisting of a two dimensional periodic refractive index structure around the core. The novel fibers guide the light by total internal refraction (TIR) or photonic bandgaps (PBG) effect. We investigate properties of the PCFs and the photonic liquid crystal fibers (PLCFs) numerically by using the plane wave expansion method and the finite element method.
By destroying the symmetry of fiber structure, we demonstrate that the birefringence is increased by 80%. The intensified birefringence allows us to design the high birefringent PCF sensors. Details are discussed and the monochromatic and dynamic measurements are demonstrated.
PLCFs are the photonic crystal fibers filled with liquid crystals, which are thermal and electrical tunable anisotropic material. In this thesis, we focus on studying the birefringence and dispersions of the PLCFs guided by TIR and PBG effects, when the optical axis of nematic PCs are in different directions. Moreover, the effects of the anisotropism of liquid crystals to PCFs are addressed.
When the optical axial of LCs is parallel to the propagation direction, the birefringence is zero. For a positive uniaxial medium, we find the zero dispersive points shift toward the lower frequency with an increasing anisotropism. On the other hand, the anisotropism has weak influence on zero dispersive points. When the optical axial of LCs is perpendicular to the propagation direction, the birefringence aren’t zero and the anisotropism has weak influence on zero dispersive points. But, the power may be lost at other directional band.
Finally, a bi-guidance fiber which has two different guiding mechanisms at two polarization modes is proposed. According to the properties of bi-guide, we can design the optical switch and optical polarization selector. The present research gives a physical insight into PLCFs and is crucial for optoelectronic devices and biosensors.

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