共查询到19条相似文献,搜索用时 168 毫秒
1.
采用改进的化学气相沉积法和溶液掺杂法制备出掺镱石英光纤预制棒,以该预制棒为有源纤芯制备芯区直径约为30μm的双包层保偏掺镱光子晶体光纤.模拟计算得到该保偏光纤的模场面积约232μm2,双折射系数B为5×10-5.利用该光纤分别进行了脉冲激光和连续激光的放大测试实验,在国内首次实现了高效率的飞秒激光放大,2 m长的光子晶体光纤可得到1.64 W的激光输出,激光放大斜率效率为49.8%.同时5 m长的光纤还能够实现8.12 W的连续激光放大输出,斜率效率达到55.9%,具有较高的斜率效率.此外,该光纤消光比约10 dB,具有良好的保偏特性. 相似文献
2.
大模场面积掺镱双包层光纤研究 总被引:1,自引:1,他引:0
采用改进的化学汽相沉积工艺,沉积了光纤阻挡层和疏松层.结合溶液掺杂技术,研究了疏松层沉积温度、镱铝共掺工艺条件对掺镱浓度的影响,研究了大模场面积纤芯的制备工艺,实现了高浓度大模场面积掺镱双包层光纤的研制.测量并分析了光纤的光学性能参数及其激光特性,光纤芯径达到30 μm,纤芯摻镱浓度提高到4 000 ppm以上,芯数值孔径降至0.07,光纤的模场面积从113 μm2 提高到1 256 μm2,光纤的非线性效应阈值功率由12 W提高到大于128 W. 相似文献
3.
模式不稳定效应和非线性效应已经成为高功率光纤激光器中限制输出功率和光束质量进一步提升的主要障碍.采用改进的化学气相沉积工艺结合溶液掺杂技术制备25/400μm的M型掺镱双包层光纤,纤芯和中间凹陷区域的数值孔径分别为0.054和0.025.基于该光纤搭建976 nm双向泵浦全光纤结构放大器.在泵浦光功率为3283 W时,获得2285 W中心波长为1080 nm的激光输出,3 dB线宽为3.01 nm,测量的光束质量因子为1.42,且未出现受激拉曼散射现象.这是目前基于M型掺镱光纤实现的最高输出功率,通过优化光纤结构参数实现功率进一步提升是有希望的. 相似文献
4.
大模场掺镱双包层光子晶体光纤内包层新型结构研究 总被引:1,自引:1,他引:0
制备了掺镱多组分硅酸盐光子晶体光纤纤芯材料。其折射率为1.586,有效荧光半高宽为85.3 nm,荧光寿命为1.30 ms。分析了光纤结构参数对光子晶体光纤的归一化频率(单模截止条件)、数值孔径、有效模面积、非线性效应和限制损耗等参数的影响。设计了以该材料为纤芯,内包层为八边形、五层空气孔的新型结构光子晶体光纤。用有限元法对该光子晶体光纤性能进行了数值模拟。结果表明,该光纤有效模场面积为1 150 μm2;当空气孔直径为21.6 μm、孔间距为60 μm时,内包层数值孔径达到0.45。 相似文献
5.
采用MCVD方法研发了掺镱双包层光纤,并对其结构特性、荧光特性和激光特性进行了测试和研究。其D形内包层尺寸为400/450μm,数值孔径为0.36,纤芯直径约为16μm,数值孔径约为0.18。荧光谱线的范围为1 000~1 140 nm,1 030 nm处的峰宽大于50 nm。采用大功率激光二极管单端泵浦6 m长的双包层光纤,在泵浦入纤功率为61 W时, 获得了32 W的激光输出,斜率效率为64%。该光纤在高功率处未发现饱和现象,通过优化光纤参数与泵浦方式还可以提高转化效率和输出功率。实验表明该光纤可以取代进口光纤用作高功率激光器件。 相似文献
6.
采用改进化学汽相沉积结合溶液掺杂法制备了Yb/P/Al共掺的石英光纤预制棒,通过光纤芯层的组份和制备工艺的优化,实现了Yb3+的高浓度掺杂和均匀掺杂.预制棒芯层Yb2O3掺杂浓度达到~4wt.%,Yb3+在1 080 nm处荧光寿命为1 780μs.成功拉制出内包层截面形状为八边形的双包层光纤,纤芯直径为7.5 μm,包层吸收系数达到~5 dB/m@976 nm.利用拉制的掺镱双包层光纤开展了全光纤结构的掺镱光纤激光器性能测试实验,实现了5.15W的激光输出,斜率效率达到76%. 相似文献
7.
8.
9.
10.
11.
12.
13.
An extruded elliptical hole photonic crystal fibers PCF with square air-core is proposed. By using a full vector finite-element method FV-FEM and anisotropic perfectly matched layers APML, the structure and optical properties of the proposed PCF are analyzed. Simulation results show that the birefringence of the proposed photonic crystal fiber can be up to the order of 10−2, and has a flattened dispersion from 1.20 μm to 1.80 μm. The proposed PCF may have important application in super-continuum SC generation, dispersion compensation, fiber-optic sensing systems and other aspects. 相似文献
14.
Generation of a mid-infrared broadband polarized supercontinuum in As2Se3 photonic crystal fibers 下载免费PDF全文
A simplified structure of birefringent chalcogenide As 2 Se 3 photonic crystal fiber(PCF) is designed.Properties of birefringence,polarization extinction ratio,chromatic dispersion,nonlinear coefficient,and transmission are studied by using the multipole method,the finite-difference beam propagation method,and the adaptive split-step Fourier method.Considering that the zero dispersion wavelength of our proposed fiber is about 4 μm,we have analysed the mechanism of spectral broadening in PCFs with different pitches in detail,with femtosecond pulses at a wavelength of 4 μm as the pump pulses.Especially,mid-infrared broadband polarized supercontinuums are obtained in a 3-cm PCF with an optimal pitch of 2 μm.Their spectral width at 20 dB reaches up to 12 μm.In the birefringent PCF,we find that the supercontinuum generation changes with the pump alignment angle.Research results show that no coupling between eigenpolarization modes are observed at the maximum average power(i.e.,37 mW),which indicates that the polarization state is well maintained. 相似文献
15.
New nonlinear and dispersion flattened photonic crystal fiber with low confinement loss 总被引:1,自引:0,他引:1
A new nonlinear dispersion flattened photonic crystal fiber with low confinement loss is proposed. This fiber has threefold symmetry core. The doped region in the core and the big air-holes in the 1st ring can make high nonlinearity in the PCF. And the small air-holes in the 1st ring and the radial increasing diameters air-holes rings in cladding can be used to achieve the dispersion properties of the PCF. We can achieve the optimized optical properties by carefully selecting the PCFs structure parameters. A PCF with flattened dispersion is obtained. The dispersion is less than 0.8 ps/(nm km) and is larger than −0.7 ps/(nm km) from 1.515 μm to 1.622 μm. The nonlinear coefficient is about 12.6456 W−1 km−1, the fundamental mode area is about 10.2579 μm2. The confinement loss is 0.30641 dB/km. This work may be useful for effective design and fabrication of dispersion flattened photonic crystal fibers with high nonlinearities. 相似文献
16.
High birefringence and low loss circular air-holes photonic crystal fiber using complex unit cells in cladding 总被引:2,自引:0,他引:2
Tzong-Jer Yang Yuan-Fong Chau Ming-Je Sung Din Ping Tsai 《Optics Communications》2008,281(17):4334-4338
We propose a high birefringence and low loss index-guiding photonic crystal fiber (PCF) using the complex unit cells in cladding by the finite-element method. Results show that the birefringence and confinement loss in such PCF fiber is determined not only by the whole cladding asymmetry but also the shape of the PCF core. The maximal modal birefringence and lowest confinement loss of our proposed structures at the excitation wavelength of λ = 1550 nm can be achieved at 8.7 × 10−3 and 5.27 × 10−5 dB/km, respectively. 相似文献
17.
Zhanqiang Hui Dongyang Hou Youkun Zhang Shixiu Wei Junhua Xu 《Fiber and Integrated Optics》2013,32(2):91-105
ABSTRACTA novel mid-infrared Ge20Sb15Se65 chalcogenide-based single-polarization single-mode (SPSM) photonic crystal fiber (PCF) with rectangular latticed circular air holes is proposed. The properties of SPSM bandwidth, confinement loss, and nonlinearity are analyzed in the 3 μm~8 μm mid-infrared region using the finite -difference time-domain (FDTD) method. The influences of different geometrical parameters on the properties of SPSM-PCF are analyzed. All numerical computational results reveal that for the optimized geometrical parameters, the proposed PCF can deliver a SPSM region of more than 2.3814 μm with high nonlinearity of 3,705 w?1 km?1. Therefore, such a SPSM-PCF will become an excellent candidate for mid-infrared photonic. 相似文献
18.
We extend the improved effective index method (IEIM) to analyze the cladding mode of the photonic crystal fiber (PCF) and to predict cladding mode coupling in gratings. By introducing a new step-index fiber model for the PCF, the cladding mode coupling between a LP01 core mode and HE11 cladding mode in long-period gratings formed in PCF is accurately predicted by the IEIM. The fiber model works well for the PCF used here not only in predicting resonant mode coupling, but also in analyzing core and low-order cladding modes. 相似文献
19.
设计了一种新型高双折射光子晶体光纤,即其包层引入椭圆形空气孔,且以三角晶格方式周期排列,纤芯引入亚波长尺寸(~0.16 μm)的微型双孔结构阵列.采用全矢量有限元法和各向异性完美匹配层边界条件分析了该型光子晶体光纤的双折射特性和色散特性,详细介绍了该光子晶体光纤在不同的椭圆率、椭圆归一化面积、微型双孔孔径、两小孔之间间距的情况下双折射和限制损耗随波长的变化曲线.模拟结果表明,通过同时在包层和纤芯引入非对称性,获得了较高的双折射(~10-3量级)和极低(~10-4 dB/km)的限制损耗.提供了一种新的光子晶体光纤设计方法,即通过同时在包层和纤芯引入新结构来同时获得高双折射和低损耗. 相似文献