液晶光子晶体光纤THz滤波和传感特性研究

发布时间：2018-01-08 08:13

本文关键词：液晶光子晶体光纤THz滤波和传感特性研究　出处：《天津理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：THz波是介于微波和红外之间的波,具有很优秀的性质。近年来对它的研究越来越热,在科研和生活中的应用研究也越来越多,如空间通信、大气科学、安全检测领域。但太赫兹波的直接运用还比较少,主要是因为它在自由空间传播时损耗较大。太赫兹波导器件的开发和研制成为THz能否被广泛应用的关键。光子晶体光纤不同于传统光纤,其包层中有很多周期性排列的空气孔,这种特殊的结构使光子晶体光纤具有很多优秀的性质。光子晶体光纤与THz技术相结合,为THz波导器件的研究开辟出一条崭新的道路。在光子晶体光纤的空气孔中填充液晶,可以改变光子晶体光纤的结构参数,使研究范围进一步拓宽。本文首先对液晶的光学性质进行了研究,选择5CB液晶作为本文光子晶体光纤的填充材料,探究了它在温度和电压下的特性。介绍光子晶体光纤的一些结构特征,综合了目前主流的一些数值分析方法。利用有限元法,在研究具有二维周期性结构的光子晶体光纤时,给出了参数的选择条件。本文研究了液晶掺杂的光子晶体光纤在THz波段的滤波和传感特性。在调谐滤波方面,利用液晶折射率易控的特点,提出一种全新的THz滤波器设计方案,把液晶材料填充到光子晶体光纤的空气孔中,通过控制液晶的双折射率来调谐光子晶体光纤的带隙,改变太赫兹波的传输频率,达到调谐滤波的目的。讨论了反谐振模型,它可以预测带隙型光子晶体光纤损耗的最大值点。研究了带隙型光子晶体光纤的开关和滤波特性,验证了反谐振模型的正确性,这样可以利用反谐振模型来设计带隙型光子晶体光纤的结构,从而实现特定波段的调谐滤波。在传感方面,利用液晶的可调谐性,分析研究了带隙型光子晶体光纤在温度和电压环境下的传感特性,比较了在温度和电场作用下,有效折射率、限制损耗、有效模场面积的不同特点。
[Abstract]:The THz wave is between microwave and infrared wave, has excellent properties. In recent years, the research on it is more and more hot, applied research in scientific research and life are more and more, such as space communication, atmospheric science, security detection. But the direct application of terahertz wave is still relatively small, mainly because of the larger it spread in free space loss. The development of terahertz waveguide devices and the development of the THz can be widely used as key. Photonic crystal fiber is different from the traditional fiber, the cladding air holes in a lot of periodic arrangement, this special structure makes the photonic crystal fiber has many excellent properties of photonic crystal fiber and THz. Technology combine to create a new way for the study of THz waveguide devices. Filling liquid crystal in the air hole photonic crystal fiber, can change the structure parameters of the photonic crystal fiber, which makes the research scope To further expand. Firstly, the optical properties of liquid crystal have been investigated, choose 5CB as filling material in liquid crystal photonic crystal fiber, explore it in the temperature and voltage characteristics. Some structural characteristics of the photonic crystal fiber, the current mainstream method. Some numerical analysis by finite element method with photonic crystals the fiber of two dimensional periodic structure in the study, select the conditions of parameters are given. The paper studies the filtering and sensing properties of photonic crystal fiber doped liquid crystal in THz band. The tunable filter, rate and easy to control by using liquid crystal refractive index, we propose a new THz filter design, the liquid crystal material is filled into the the air hole photonic crystal fiber, the birefringence of the liquid crystal is controlled to the rate of band gap tuning of photonic crystal fiber, change the transmission frequency of THz wave, achieve tunable filter Objective. To discuss the anti resonance model, which can predict the maximum band gap photonic crystal fiber loss. Studies with switch and filter characteristics of gap photonic crystal fiber, verify the correctness of the anti resonance model, it can use the anti resonant model to design the structure of photonic bandgap photonic crystal fibers. In order to achieve specific wavelength tunable filter. In the sensor, using a liquid crystal tunable, analysis of the band gap photonic crystal fiber sensing characteristics in temperature and voltage environment, compares the temperature and electric field, the effective refractive index, the confinement loss, different characteristics of the effective mode area.

【学位授予单位】：天津理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN253

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