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改善波形并增敏的光纤光栅温度传感技术 总被引:3,自引:1,他引:2
选用热膨胀系数较大的聚合物和某种偶联材料,采用特殊工艺用其对裸光纤光栅进行封装,消除了封装过程中所带来的光纤光栅啁啾现象,极大地改善了光纤光栅反射波的波形,提高了封装测试过程的重复性,为波长解调解决了一大难题.在30.6℃~120℃范围内,测量过程中波形很好并几乎不变,温度灵敏度为0.1173 nm/℃,温度分辨率为<0.43℃,比裸光纤光栅增加了11倍;平均灵敏度增敏倍数γ′=10.34,与理论计算灵敏度增敏倍数γ=10.76符合得比较好.聚合物封装光纤光栅的温度响应曲线具有很好的线性. 相似文献
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大范围光纤布拉格光栅温度传感器增敏实验研究 总被引:11,自引:0,他引:11
简要分析了光纤布拉格光栅的温度响应及增敏原理,采用特殊耐高温有机聚合物对光纤光栅进行温度增敏封装,并通过改进光纤光栅的聚合物封装固化工艺,使用某种有机硅导热胶减小有机聚合物与套管材料的粘合度,消除了封装过程中由于聚合物材料不均匀收缩引起的光纤光栅反射谱啁啾化,实现20~180℃范围内光纤光栅传感器对温度高灵敏度测量。实验结果表明.聚合物封装光纤光栅传感器温度响应灵敏度在20~130℃为0.05nm/℃,在130~180℃达到了0.22nm/℃,并在两个区域保持较好的线性与重复性。此结构传感器封装工艺简单,易于实现,可用于高温恶劣环境下的温度单参量测量。 相似文献
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报道了利用偶联技术封装光纤光栅压力传感器的新方案.通过采用特殊聚合物材料将光纤光栅封装于金属管中,并采用偶联材料分别与聚合物和光纤以化学键偶联的工艺,解决了由于有机弹性体聚合物的弹性模量(1.2×105 N/m2)与光纤光栅的弹性模量(7×1010 N/m2)相差很大,在压强较大时易导致光纤光栅与聚合物材料之间的撕裂滑脱问题,改善了光纤光栅压力响应特性.封装后的光纤光栅压力的线性测量范围为0.04 MPa~0.6 MPa,压力响应灵敏度为-4.48 nm/MPa,与裸光栅压力响应灵敏度-0.003063 nm/MPa相比,增敏了1463倍.利用实验中所使用光谱仪0.05 nm的分辨率,压强测量准确度为±0.01 MPa,线性度为0.9978. 相似文献
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光纤光栅边孔封装技术 总被引:1,自引:0,他引:1
提出了一种新型的光纤光栅压力增敏封装技术——边孔封装技术,它通过改变封装体的几何结构实现了高倍数的压力增敏效果,较大程度减小了压力增敏倍数对聚合物材料参量的依赖性。采用有限元理论建立了边孔封装结构的压力传感模型,分析了封装体几何结构变化对封装后压力灵敏度的影响。采用聚合物材料进行了封装制作实验,测量结果表明封装后光纤光栅的压力灵敏度为5251 pm/MPa,是封装前压力灵敏度的1750倍,并将交叉敏感问题改善了近三个数量级,可满足高精度水下压力测量的应用要求。 相似文献
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聚合物封装的高灵敏度光纤光栅温度传感器及其低温特性 总被引:10,自引:0,他引:10
介绍了一种新型的光纤光栅温度传感器。这种光纤光栅温度传感器使用了特殊的工艺将光纤布拉格光栅封装于一种热膨胀系数较大的有机聚合物基底中 ,使得传感器的温度灵敏性比裸光纤光栅提高了 12 .3倍 ,其温度灵敏度系数KT 达到 82 .6 9× 10 -6/℃。在 - 80~ 0℃的低温度范围内 ,对这种新型光纤光栅温度传感器的反射谱进行了测量。研究了这种新型光纤光栅温度传感器的低温特性 ,并与裸光纤光栅和铝基封装的光纤光栅进行了比较 ,结果表明这种新型的光纤光栅温度传感器具有很好的低温响应特性。 相似文献
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(001)和(111)取向的张应变量子阱光学特性的比较 总被引:5,自引:1,他引:4
以(001)和(111)价带Lutinger-Kohn哈密顿量为基础,讨论了这两种取向的量子阱的能带结构、态密度(DOS)、跃迁矩阵元和增益特性。由于材料结构的各向异性,(111)取向的量子阱在平行生长面内有较小的重空穴有效质量,无应变和压应变激光器可以很好地利用这一点。而(001)取向的量子阱虽有较小的平面内轻空穴有效质量,但并不比(111)量子阱的小多少;加上(001)量子阱的价带耦合效应强,使其DOS比(111)量子阱的大,在相同载流子注入下,张应变(111)量子阱的增益系数比相应(001)量子阱的要高。所以张应变(111)量子阱激光器仍然比相应的(001)量子阱激光器性能要好。可以认为匹配和压应变的(111)激光器优异的性能不仅来自小的面内有效质量,也来自于弱的价带耦合效应。 相似文献
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Durga Prasad Sapkota Madhu Sudan Kayastha Koichi Wakita 《Optical and Quantum Electronics》2013,45(1):35-43
We have compared and analyzed theoretical investigation for the possibility of extreme reductions in the linewidth enhancement factor (??-factor) in strained layer quantum-well (QW) lasers between AlGaInAs and InGaAsP material. Valence band effective masses and optical gain in both types of QW lasers under compressive strain have been calculated using 4 ×?4 Luttinger?CKohn Hamiltonian. We have used Kramers?CKronig relations to calculate the refractive index change due to carrier induced. The ??-factor was up to 1.61 times smaller in AlGaInAs QW than in InGaAsP QW laser. The material differential modal gain and carrier induced refractive index change was found to be approximately 1.38 times larger and 1.15 times smaller respectively, in the previous material QW than in the latter QW laser. We also compared our results to the previously reported results for both QWs lasers. 相似文献
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Valence band structure and density of states effective mass model of biaxial tensile strained silicon based on k·p theory 下载免费PDF全文
After constructing a stress and strain model, the valence bands of in-plane biaxial tensile strained Si is calculated by k·p method. In the paper we calculate the accurate anisotropy valance bands and the splitting energy between light and heavy hole bands. The results show that the valance bands are highly distorted, and the anisotropy is more obvious. To obtain the density of states (DOS) effective mass, which is a very important parameter for device modeling, a DOS effective mass model of biaxial tensile strained Si is constructed based on the valance band calculation. This model can be directly used in the device model of metal-oxide semiconductor field effect transistor (MOSFET). It also a provides valuable reference for biaxial tensile strained silicon MOSFET design. 相似文献
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Y.-K. Kuo J.-R. Chen M.-L. Chen B.-T. Liou 《Applied physics. B, Lasers and optics》2007,86(4):623-631
The physical and optical properties of compressively strained InGaAsP/InGaP quantum wells for 850-nm vertical-cavity surface-emitting
lasers are numerically studied. The simulation results show that the maximum optical gain, transparency carrier densities,
transparency radiative current densities, and differential gain of InGaAsP quantum wells can be efficiently improved by employing
a compressive strain of approximately 1.24% in the InGaAsP quantum wells. The simulation results suggest that the 850-nm InGaAsP/InGaP
vertical-cavity surface-emitting lasers have the best laser performance when the number of quantum wells is one, which is
mainly attributed to the non-uniform hole distribution in multiple quantum wells due to high valence band offset.
PACS 42.55.Px; 78.20.-e; 78.20.Bh; 78.30.Fs 相似文献
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能带工程通过改变材料的能带结构可以显著提升其电学和光学性质,已广泛应用于半导体材料的改性研究.双轴张应力和Sn组分共同作用下的Ge_(1-x)Sn_x合金,不仅可以解决直接带隙转变所需高Sn组分带来的工艺难题,而且载流子迁移率会显著提升,在单片光电集成领域有很好的应用前景.根据形变势理论,分析了(001)面双轴张应变Ge_(1-x)Sn_x的带隙转变条件,并给出了在带隙转变临界点Sn组分和双轴张应力的关系;采用8κ·p方法,得到了临界带隙双轴张应变Ge_(1-x)Sn_x在布里渊区中心点附近的能带结构,进而计算得到电子与空穴有效质量;基于载流子散射模型,计算了电子与空穴迁移率.计算结果表明:较低Sn组分和双轴张应力的组合即可得到直接带隙Ge_(1-x)Sn_x合金,且直接带隙宽度随着应力的增大而减小;临界带隙双轴张应变Ge_(1-x)Sn_x具有极高的电子迁移率,空穴迁移率在较小应力作用下即可显著提升.考虑工艺实现难度和材料性能两个方面,可以选择4%Sn组分与1.2 GPa双轴张应力或3%Sn组分与1.5 GPa双轴张应力的组合用于高速器件和光电器件的设计. 相似文献
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SONG JianJun ZHANG HeMing HU HuiYong DAI XianYing & XUAN RongXi Key Laboratory of Wide B -Gap Semiconductor Materials Devices School of Microelectronics Xidian University Xi’an China 《中国科学:物理学 力学 天文学(英文版)》2010,(3)
The strained Si techique has been widely adopted in the high-speed and high-performance devices and circuits. Based on the valence band E-k relations of strained Si/(111)Si1-xGex, the valence band and hole effective mass along the [111] and [-110] directions were obtained in this work. In comparison with the relaxed Si, the valence band edge degeneracy was partially lifted, and the significant change was observed band structures along the [111] and [-110] directions, as well as in its corresponding hole eff... 相似文献
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The optical and electrical properties of compressively strained GaInSb/GaInAlSb mid-infrared quantum well lasers are numerically studied solving one-dimensional Schrödinger equation using finite difference method. The simulation results demonstrate that band-mixing effects and effective mass of hole are reduced when the well is compressively strained. The strain-dependent optical and differential gains are evaluated for 0.6, 0.9, 1.21, and 1.52% compressively strained quantum well and found maximum when well is strained by 1.52%. The emission wavelength for the proposed laser can be tuned from 2.40 to 2.26 μm due to change in compressive strain from 0.60 to 1.52% at temperature 300 K. For the range of strain, the shift in wavelength is found from 2.38 to 2.24 μm at temperature 275 K. The results obtained from PSPICE simulation indicate that, the optical output power and threshold current are strongly depend on the number of wells and found to be almost constant for the number of wells three and above. 相似文献
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采用低压金属有机化学气相外延设备进行了1.3μm压应变量子阱材料、张应变量子阱材料和混合应变量子阱材料的生长研究.通过x射线双晶衍射和光致发光谱对生长材料进行测试和分析.基于四个压应变量子阱和三个张应变量子阱交替生长的混合应变量子阱(4CW3TW)结构有源区,并采用7°斜腔脊型波导结构以有效抑制腔面反射,经蒸镀减反膜后,半导体光放大器光纤光纤小信号增益达21.5dB,在1280—1340nm波长范围内偏振灵敏度小于0.6dB.
关键词:
偏振无关
应变量子阱
半导体光放大器
减反膜 相似文献