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光子晶体光纤布拉格光栅传输谱特性的分析 总被引:5,自引:3,他引:2
研究光子晶体光纤中光纤光栅的传输谱特性对于研制基于光子晶体光纤的光纤光栅器件有着重要的意义。结合耦合模理论和光束传输相关函数方法,对一种典型光子晶体光纤中的布拉格光栅(FBG)传输谱进行了理论分析。比较了光子晶体光纤中布拉格光栅与常规布拉格光栅的传输谱。数值分析了光纤截面结构变化对于光栅传输谱的影响,并给出这种影响的定性解释。计算结果显示,与常规光纤光栅相比,包层模共振引起的损耗峰与正反向纤芯模耦合引起的损耗峰可以相比拟,而包层模共振的间隔也比常规光纤中光纤光栅的包层模共振间隔要大。同时给出了晶体光纤截面上空气孔的占空比,空气孔的排布层数对于传输谱影响的规律。 相似文献
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正弦锥光纤光栅的数值计算分析 总被引:1,自引:0,他引:1
本文利用耦合模方程对正弦锥光纤光栅的反射谱进行了较为详细的计算和分析,发现,这种光纤光栅的反射谱与普通均匀周期光栅的反射谱有着很大的不同,通过控制光栅锥的形状,可得到类似于梳状滤波器的功能,对这种新型光栅在光纤激光器等方面的应用有指导意义。 相似文献
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线性啁啾光纤光栅的耦合模理论分析 总被引:4,自引:1,他引:3
利用耦合模理论对线性啁啾光纤光栅的反射谱进行了分析,并详细讨论了耦合系数、啁啾系数、高斯分布参量、光栅长度对线性啁啾光纤光栅的反射带宽和最大反射率的影响. 相似文献
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基于光纤Bragg光栅(FBG)反射复振幅相移对FBG法布里-珀罗腔透射谱的影响,分析了传统耦合模理论计算均匀FBG反射复振幅相移产生误差的原因.引入折射率分布初始相位参数描述FBG折射率分布纵向的微小偏移,用真实的反透射系数代替简明形式的反透射系数,对传统耦合模理论进行了修正,增加了与折射率分布初始相位参数有关而与波长无关的相位因子.在此基础上进一步对计算非均匀FBG的传输矩阵法的相位进行了修正.修正后的快速计算结果用于FBG法布里-珀罗腔透射谱的计算,可反映折射率分布初始相位参数对透射峰波长位置的影响,与Rouard 算法及实验值均有较好的一致性.
关键词:
光纤Bragg 光栅
法布里-珀罗腔
耦合模理论 相似文献
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饱和长度对少模光纤光栅影响的数值仿真 总被引:1,自引:0,他引:1
对折射率剖面非均匀的少模光纤Bragg光栅(FM-FBG)的反射特性进行了数值仿真,研究了光纤侧面紫外曝光法制作的光纤光栅中饱和长度的影响.用试射法(shooting)数值求解了耦合模方程,得到FM-FBG的反射谱.仿真结果表明,在纤芯和包层边界的最大光致折射率变化量和纤芯吸收因子不变的情况下,随着纤芯折射率变化的饱和长度的增大,LP01和LP11模间的互耦合反射峰呈抛物线形变化,当饱和长度增大到一定值后,互耦合反射峰随饱和长度的增大而逐渐减小并最终消失;同阶LP模的自耦合反射峰随饱和长度的增大而增大. 相似文献
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To model chirped fiber Bragg gratings (FBGs) for dispersion compensation in optical fibers a novel method of single expression (MSE) is used. The reformulation of Helmholtz's equation in the MSE to the full set of first-order differential equations leads to dealing with the electric field amplitude, its derivative, power flow density and phase distributions in any aperiodic media. The phase derivative obtained numerically permits to compute the dispersion slope in the time delay of investigated chirped gratings. Reflective and time delay spectra of linearly chirped gratings of different lengths and chirp coefficients are computed. A self-similarity law for the gratings of the same strength but different lengths and chirp coefficients is revealed. The apodization of gratings is applied to reduce sidelobes in gratings' reflection spectra and eliminate oscillations in the time delay characteristics. 相似文献
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To model chirped fiber Bragg gratings (FBGs) for dispersion compensation in optical fibers a novel method of single expression
(MSE) is used. The reformulation of Helmholtz’s equation in the MSE to the full set of first-order differential equations
leads to dealing with the electric field amplitude, its derivative, power flow density and phase distributions in any aperiodic
media. The phase derivative obtained numerically permits to compute the dispersion slope in the time delay of investigated
chirped gratings. Reflective and time delay spectra of linearly chirped gratings of different lengths and chirp coefficients
are computed. A self-similarity law for the gratings of the same strength but different lengths and chirp coefficients is
revealed. The apodization of gratings is applied to reduce sidelobes in gratings’ reflection spectra and eliminate oscillations
in the time delay characteristics. 相似文献
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This paper provides an overview and technology update of a dispersion
management component made from chirped fiber Bragg gratings. The history and
technology of fiber Bragg gratings (FBGs) have been extensively covered in
several excellent review articles, [1-6] book chapters, [7] and books. [8,9]
We give a brief overview of fiber Bragg grating technology in this section
and then focus on the details concerned with construction and performance of
dispersion management devices in optical communications systems with a
single broadband long-length grating used in reflection. Sampled chirped
grating are sometimes referred to as broadband devices, but they actually
have a narrow bandwidth of operation that is periodically repeated across a
given spectral range. Although these periodic devices have shown promise as
dispersion management devices in communications systems, they will not be
discussed in this paper. 相似文献
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Results are presented on the efficient spectral manipulation of uniform and chirped Bragg reflectors inscribed in microstructured optical fibers utilizing short lengths of ferrofluids infiltrated in their capillaries. The infiltrated ferrofluidic defects can generate either parasitic reflection notch features in uniform Bragg reflectors of up to 80% visibility and ~0.1 nm spectral shift or tunability of the bandwidth and strength reflection up to 100% when introduced into chirped gratings. Spectra are presented for different spatial positions and optical characteristics of the ferrofluidic section. 相似文献
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利用遗传算法优化线性啁啾光栅性能 总被引:3,自引:2,他引:1
针对制作町用于40 Gb/s全光色散补偿的宽带线性啁啾光栅时出现带内群时延纹波波动较大等问题.提出了一种通过设计和改变切趾函数的参量来优化线性啁啾光栅的新方法.该方法实现简单.只需根据需要设计具有不同滚降特性的切趾函数,同时利用遗传箅法来优化切趾参量.结合传输矩阵法经过200代获得了低带内时延纹波的线性啁啾光栅.数值结果验证了采取非对称分段切趾法在保持反射谱宽和平坦性的同时可以抑制带内群时延纹波的优越性.利用该方法制作了反射谱工作带宽为1.06 nm、时延纹波不超过45.60 ps、可用于大容量密集波分复用系统(DWDM)色散补偿的线性啁啾光纤光栅. 相似文献
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A high channel-count comb filter based on multi-concatenated sampled chirped fiber Bragg gratings(MC-SCFBGs) is proposed and optimally designed by using several chirped gratings with different fundamental grating periods,instead of non-grating sections of SCFBGs.The numerical simulations of the reflection spectra show that the channel spacing and the channel bandwidth in MC-SCFBGs are smaller than those in multi-concatenated chirped fiber Bragg gratings(MC-CFBGs) and that the spectral bandwidth of MC-SCFBGs can be greatly broadened by increasing the cascade number of the grating sections in each sampling period. 相似文献
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We propose and demonstrate an efficient and simple wavelength switchable dual-wavelength passively mode-locked fiber ring
laser based on a semiconductor saturable absorber mirror (SESAM) and a cascaded sequence of fiber Bragg gratings (FBGs). The
efficient self-starting mode-locked operation was realized with a SESAM. Dual-wavelength pulses with a wavelength spacing
of 12.49 nm were obtained which was determined by the reflection peaks of the FBGs used in the experiment. In addition, by
rotating the polarization controllers (PCs), the switchable dual-wavelength operation was simply achieved via exploiting wavelength-dependent
loss mechanism. 相似文献
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This paper presents an overview of fiber Bragg gratings (FBGs) fabrication principles and applications with emphasis on the
chirped FBG used for dispersion compensation in high-speed optical communication systems. We discuss the range of FBG parameters
enabled by current fabrication methods, as well as the relation between the accuracy of FBG parameters and the performance
of FBG-based dispersion compensators. We describe the theory of the group delay ripple (GDR) generated by apodized chirped
fiber gratings using the analogy between noisy gratings and superstructure Bragg gratings. This analysis predicts the fundamental
cutoff of the high frequency spatial noise of grating parameters in excellent agreement with the experimental data. We review
the iterative GDR correction technique, which further improves the FBG quality and potentially enables consistent fabrication
of FBG-based dispersion compensators and tunable dispersion compensators with unprecedented performance. 相似文献
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Proposal and realization for a broadband all-fiber non-uniformly spaced multi-channel optical filter
In this paper, we propose a broadband all-fiber non-uniformly spaced multi-channel optical filter, which is based on the utilization of paired multi-channel fiber Bragg gratings (FBGs) located at two arms of an interferometer. Unlike the traditional optical comb filter, the channel spacing may be either linearly or nonlinearly chirped. Serving as an example, two identical linearly-chirped 51-channel FBGs have been successfully employed to demonstrate the proposed filter experimentally. 相似文献