拉锥型啁啾光纤光栅滤波器的研究

本文主要对拉锥型啁啾光纤光栅滤波器进行详细的理论分析和实验研究. 结合传输矩阵法, 谐振理论和耦合模理论, 深入细致地分析了啁啾光纤光栅自身参数 (光栅长度, 折射率调制幅度, 啁啾系数), 拉锥参数和锥区损耗对拉锥型啁啾光纤光栅滤波器透射谱的影响, 并研究拉锥对啁啾光纤光栅各波长反射率影响. 在此基础之上进行相应的数值仿真及实验验证, 数值仿真与实验结果基本一致. 关键词： 光栅拉锥 啁啾光栅 传输矩阵法 滤波器     

全光纤型微环谐振器的研制

环形谐振器因体积小、功能强、结构简洁等优点长期以来一直在光无源、有源器件的设计和制作中发挥着重要的作用。对光纤的弯曲损耗特性进行了深入分析,指出只有采用微细光纤才能降低全光纤法所制作的环形谐振器的尺寸,加宽器件的自由光谱范围(FSR)获得更好的精细度和品质因子。然后,在改进熔融拉锥技术的同时,保持慢变、绝热条件拉制出在80 mm长度范围内具有良好均匀性、半径为5μm的高质量微细光纤,在此基础上采用自缠绕法研制出半径仅为500μm,谐振效果明显加强的全光纤型微环谐振器,从而很好地解决了集成型微环谐振器较高的弯曲损耗和连接损耗问题。     

对光纤布拉格光栅法布里-珀罗腔纵模间隔问题的研究

对光纤布拉格光栅(FBG)法布里-珀罗(F-P)腔的透射特性进行了深入分析,指出了FBG F-P腔透射谱中纵模位置的影响因素,讨论了与普通F-P腔的联系和区别.应用光栅的有效镜面模型对FBG反射主瓣内反射系数的相位因子进行线性模拟,定义了FBG有效长度的概念并得出其表达式.提出将FBG的有效长度纳入到FBG F-P腔的等效腔长中,用等效腔长来计算FBG F-P腔中的纵模间隔.数值仿真和实验结果都表明,用等效腔长计算所得的纵模间隔与实际的FBG F-P腔中的纵模间隔符合很好,误差极小. 关键词： 光纤布拉格光栅 法布里-珀罗腔 纵模间隔 有效镜面模型     

高非线性光纤正常色散区脉冲尾部非频移分量演化

基于广义非线性薛定谔方程(对皮秒双曲正割光脉冲在高非线性光纤(highly nonlinear fiber, HNLF)正常色散区传输时尾部非频移分量的演化情况进行了理论研究.研究结果表明:交叉相位调制(cross-phase modulation, XPM)和受激拉曼散射(stimulated Raman scattering, SRS)在其演化过程中起主导作用,而三阶色散对其直接影响较小.在XPM效应的作用下,处于脉冲前沿和后沿尾部的非频移分量逐渐减弱,其光谱分别发生红移和蓝移,这一过程具有对称性; SRS会加速前沿尾部非频移分量的减弱过程,而减缓后沿的减弱过程,这一现象在脉冲峰值功率较高时更为明显.从脉冲尾部非频移分量演化角度分析了啁啾脉冲在HNLF正常色散区的光谱和波形特性.     

All-fibre micro-ring resonator based on tapered microfibre

In this paper, bendloss characteristics of an optical fibre are investigated in detail, and the results show that the resonator with a smaller ring radius, wider free spectrum range （FSR）, higher fineness （f） and quality-factor （Q） can be achieved by using microfibres. Based on the improved fused taper technique, a high-quality microfibre with 5 ttm radius has been fabricated, and an all-fibre micro-ring resonator with a radius of only 500μm is realized using self-coiling coupling method. The good-resonant characteristic makes the all-fibre device be expected to avoid bendloss and connection loss associated with planar waveguide integration.     

Multi-wavelength fiber ring laser based on a chirped moiré fiber grating and a semiconductor optical amplifier

A simple and cost-effective multi-wavelength fiber ring laser based on a chirped Moiré fiber grating (CMFG) and a semiconductor optical amplifier (SOA) is proposed.Stable triple-wavelength lasing oscillations at room temperature are experimentally demonstrated.The measured optical signal-to-noise ratio (SNR) reaches the highest value of 50 dB and the power fluctuation of each wavelength is less than 0.2 dB within a 1-h period.To serve as a wavelength selective element,the CMFG possesses excellent comb-like ...     

Switchable Multi-Wavelength Erbium-Doped Fiber Lasers based on a Mach-Zehnder Interferometer Using a Twin-Core Fiber

A switchable multi-wavelength erbium-doped fiber ring laser based on a compact in-fiber Mach-Zehnder interferometer comb filter at room temperature is presented. The comb filter is formed by splicing a section of twin-core fiber between two single mode fibers. By adjusting the states of the polarization controller appropriately, the laser can be made to operate in stable single-, dual- and three-wavelength lasing states. The operation principle is based on spectral hole burning induced by the saturated effect and polarization hole burning.     

基于啁啾相移光纤光栅的滤波器设计及应用

相移光纤光栅作为透射型带通滤波器件降低了使用成本和插入损耗.在光通信和传感领域有着较高的应用价值.啁啾相移光纤光栅的透射峰波长和数量由相移点的位置和数量来确定,透射峰特性受相移量的影响.采用分段切趾的方法获得满足光通信要求的滤波特性,利用传输矩阵法分析了切趾前后透射峰特性的变化,结果表明:切趾改善了滤波器的幅度和相位响应,依据滤波器的设计要求选取不同的切趾函数以及切趾比例;切趾还大大减弱了透射峰波长和深度对相移量的敏感度,适当切趾后相移量的影响可以忽略.并提出一种应用双通道啁啾相移光纤光栅滤波器产生脉冲毫米波副载波信号的方案.     

Stable single longitudinal mode erbium-doped silica fiber laser based on asymmetric linear three-cavity structure

We present a stable linear-cavity single longitudinal mode (SLM) erbium-doped silica fiber laser. It consists of four fiber Bragg gratings (FBGs) directly written in a section of photosensitive erbium-doped fiber (EDF) to form asymmetric three-cavity structure. The stable SLM operation at a wavelength of 1545.112 nm with a 3-dB bandwidth of 0.012 nm and an optical signal-to-noise ratio (OSNR) of about 60 dB is verified experimentally. In laboratory condition, the performance of power fluctuation of less than 0.05 dB observed from the power meter for 6 h and wavelength variation of less than 0.01 nm obtained from the optical spectrum analyzer (OSA) for about 1.5 h are demonstrated. The gain fiber length is no longer limited to only several centimeters for SLM operation because of the excellent mode-selecting ability of the asymmetric three-cavity structure. The proposed scheme provides a simple and cost-effective approach to realizing a stable SLM fiber laser.