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Short photonic crystal fibers (PCFs) with different tapered waist diameter are made to extend the continuum spectrum in the visible range. The diversification of output continuum spectrum with the diameter of the tapered waist is experimentally observed. An all fiber visible supercontinuum source with 1.88 W output is demonstrated in our experiments. To the best of our knowledge, it is the highest all fiber visible supercontinuum generation in tapered PCF, pumping by picosecond pulse at 1064 nm. The suitably designed short tapered PCF can extend the visible spectrum, while, how to preserve the tapered waist is crucial for the all fiber visible supercontinuum source in the practical applications. 相似文献
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提出一种基于铜沉积石墨烯涂层光子晶体光纤马赫-曾德干涉的硫化氢气敏传感器.将45mm光子晶体光纤两端与单模光纤进行拉锥熔接,使得光子晶体光纤的空气孔熔接时形成塌陷层,更好地激发包层模式,形成基于马赫-曾德结构的干涉仪.采用单层石墨烯粉体,加入异丙醇分散液,反复浸涂至光子晶体光纤包层表面形成石墨烯涂层,并沉积铜纳米颗粒,使传感器对硫化氢气体具有高的响应度.实验结果表明,在硫化氢气体浓度为0~60ppm范围内,随着被测气体浓度不断增大,其输出光谱呈现明显蓝移,传感器灵敏度为0.042 03nm/ppm,且线性度良好.该传感器成本低、灵敏度高、结构简单,适用于低浓度硫化氢气体的在线监测. 相似文献
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光子晶体光纤气体传感灵敏度的有限差分法分析 总被引:1,自引:1,他引:0
提出了一种适合于高灵敏度气体传感器的新型光子晶体光纤结构.采用全矢量频域有限差分方法,研究了基于不同结构光子晶体光纤的气体传感器的相对灵敏度.由全矢量频域有限差分法,通过直接求解由麦克斯韦方程组导出的标准特征值方程,可以得到光纤中可能存在的不同模式的传播常量、电场分布和磁场分布.分别给出了三种不同结构光子晶体光纤在波长为1.3312 μm处,与结构参量变化对应的相对灵敏度变化以及在不同波长情况下的相对灵敏度变化.结果证明,该新结构具有较其它代表性的折射率引导型光子晶体光纤结构更高的灵敏度,特别适合作气体传感器. 相似文献
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针对锥形半导体激光器中的脊形波导区宽度较小的问题,对半导体激光芯片制造中的刻蚀标记及刻蚀方法进行了研究。提出对于锥形半导体刻蚀中的脊型区域和锥形区域,采用不同精度的双标记刻蚀方法,细化对脊形波导和锥形波导的刻蚀中的对准问题,并使光刻标在不同的光刻版上相错位排列,在相应光刻版中相互遮挡,反复刻蚀中保证相应的光刻标清晰、完整。刻蚀后的芯片在电流为7 A时获得了中心波长963nm、连续功率4.026 W、慢轴方向和快轴方向激光光束参数乘积分别为1.593 mm·mrad和0.668 mm·mrad的激光输出。 相似文献
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Seon Young Ryu Hae Young Choi Jihoon Na Eunseo Choi Gil-Ho Yang Byeong Ha Lee 《Optical and Quantum Electronics》2005,37(13-15):1191-1198
We report a photonic crystal fiber (PCF)-based optical coherence tomography (OCT) system, in which conventional single-mode fiber for the transmission line and the fiber coupler for the beam splitter/combiner are replaced with PCF and PCF coupler. The PCF coupler fabricated using the fused biconical tapered (FBT) method showed a nearly flat coupling ratio over a broad spectral bandwidth of 400 nm, which provided an axial resolution of 3-μm for OCT imaging. With a white-light source, the 8-μm thick air gap between two stacked cover glasses was measured, and with a conventional superluminecent diode (SLD) source, the in vitro images of rat eye and Misgurnus mizolepis skin were successfully obtained. The PCF and PCF coupler might enable a white-light as the source for the cost effective and high-resolution OCT system. 相似文献
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A subwavelength holey plasmonic structure was proposed by adiabatically tapering a photonic crystal fiber (PCF) and subsequently metalizing the cleaved end facet. By coupling a white light into the PCF side, we experimentally observed an enhanced optical transmission in the spectral domain through the plasmonic structure at the tapered end. We further showed numerically that the proposed device renders a focused directional beam, due to its Fresnel-zone-like configuration and the plasmonic lensing effects. 相似文献
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Reported are experimental results from investigations of the sensing properties of long-period gratings (LPGs) recorded in two different geometries of photonic crystal fibre (PCF): a large-mode area PCF and an endlessly single mode PCF. The LPGs have been characterised for their sensitivity to temperature, bending, surrounding index and strain. The LPGs in both fibres have been found to have negligible temperature sensitivity whilst exhibiting useful strain sensitivities. Strong directional bend sensitivity is shown by one PCF whilst the other shows good non-directional bend sensitivity. The fibres exhibit differing sensitivities to surrounding refractive index. 相似文献
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A sensor probe with a microstructure, which is used for near-field scanning optical microscopes, plays an important role in the resolution and detection sensitivity of the microscope system. In this study, we devised a system for sharpening optical fibers, by which we could fabricate tapered tips of silica-based optical fibers reproducibly in a desired shape by controlling the solution temperature, etching time, and etching depth when applying chemical etching techniques using hydrofluoric acid. Furthermore, we evaluated the diameter of the core tip of an optical fiber by measuring the near-field pattern and comparing it with the Gaussian beam pattern of a non-edge-etched optical fiber. A strong correlation between the ratio of the 1/e2-value width of the beam profile of the near-field pattern to that of the Gaussian beam and the diameter of the extreme tip of the core became apparent. © 2005 The Optical Society of Japan 相似文献
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We fabricate a simple, compact, and stable temperature sensor based on a liquid-sealed photonic crystal fiber (PCF) in-line nonpolarimetric modal interferometer. Different from other reported PCF devices, it does not need expensive polarimetric devices, and the liquid is sealed in one fiber. The device consists of a stub of isopropanol-filled PCF spliced between standard single-mode fibers. The temperature sensitivity (-166 pm/°C) increases over an order of magnitude compared with those of the previous sensors based on air-sealed PCF interferometers built via fusion splicing with the same mechanism. In addition, the refractive index sensitivity also increases. Higher temperature sensitivity can be realized by infiltrating some liquid having a higher thermo-optic coefficient into the microholes of the PCF. 相似文献
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Photonic crystal fiber coupler 总被引:3,自引:0,他引:3
Fiber couplers made with photonic crystal fibers (PCF) are reported. Two types of PCF were fabricated by means of stacking a group of silica tubes around a silica rod and drawing them. The fiber couplers were made by use of the fused biconical tapered method. With a fiber that had five hexagonally stacked layers of air holes, a 33/67 coupling ratio was obtained, and with a one-layer four-hole fiber, a 48/52 coupling ratio was obtained. The fabrication processes and the characteristics of the PCFs and the PCF couplers are presented. 相似文献
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为了解决传统光纤传感在传感不同物理参量时需要多个传感器的问题,并拓展光纤在同时传感多参量方面的应用,结合光子晶体光纤(PCF)中基模与高阶模光的不同传感特性以及气体吸收传感原理,在PCF传感温度、应力双参量的实验基础上,应用理论分析的手段探讨了同时传感温度、应力和气体浓度3种参量的方法。给出了3种参量的计算式并进行了数值模拟,最后设计了一套相对简单、性价比高的传感解调系统。理论分析和数值模拟表明:温度在0℃以上时可以获得高于0.98 pm/℃的温度灵敏度;基模光应力灵敏度为1.2 pm/,高阶模光可获得高于0.83 pm/的应力灵敏度;长度较短的光子晶体光纤能够测量较高的气体浓度。本方案使用2个写入光纤布拉格光栅(FBG)的PCF作为传感器同时传感温度、应力和气体浓度3种参量,能够有效降低传感成本,拓宽气体、液体传感研究的思路。 相似文献
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Huei-Min Yang 《Optik》2009,120(17):905-910
This study proposes a new scheme of the tapered hyperbolic-end fiber (THEF) by etching the fiber end in a hydrofluoride (HF) solution with a thin layer of oil floating on top of the HF. This study makes it possible to fabricate the hyperbolic microlenses using unique etching and fusion techniques. Compared with previous hemispherical microlenses, the study shows that a THEF with a smaller taper angle and longer taper length fabricated by lower oil density exhibits a smaller radius of curvature, thus resulting in a better coupling efficiency. The THEF microlens results in a more than 2 dB improvement in coupling efficiency when compared with the currently available hemispherical microlenses. The calculation of the effect of oil density in HF etching solution on taper angle and taper length based on an empirical model is in agreement with the measured results. The THEFs have demonstrated up to 86% coupling efficiency for a laser with an aspect ratio of 1:1.5 at a wavelength of 1550 nm. 相似文献
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High sensitivity dual core photonic crystal fiber sensor for simultaneous detection of two samples
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Pibin Bing 《中国物理 B》2022,31(8):84208-084208
The optical control ability of photonic crystal fiber (PCF) is a distinctive property suitable for improving sensing and plasma performance. This article proposes a dual-core D-channel PCF sensor that can detect two samples simultaneously, which effectively solves the problems of coating difficulty and low wavelength sensitivity. The PCF has four layers of air holes, which dramatically reduces the optical fiber loss and is more conducive to the application of sensors in actual production. In addition, by introducing dual cores on the upper and lower sides of the central air hole, reducing the spacing between the core and the gold nanolayer, a stronger evanescent field can be generated in the cladding air hole. The optical fiber sensor can detect the refractive index of two samples simultaneously with a maximum sensitivity of 21300 nm/RIU. To the best of our knowledge, the sensitivity achieved in this work is the highest sensitivity with the dual sample synchronous detection sensors. The detection range of the refraction index is 1.35-1.41, and the resolution of the sensor is 4.695×10-6. Overall, the sensor will be suitable for medical detection, organic chemical sensing, analyte detection, and other fields. 相似文献
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We report on a microscopic Fabry-Perot interferometer whose cavity is a bubble trapped inside an optical fiber. The microcavity is formed by pressuring a photonic crystal fiber (PCF) with large voids during fusion splicing with a conventional single-mode fiber. The technique allows achieving high repeatability and full control over the cavity size and shape. It was found that the size of the PCF voids contributes to control the cavity size independently of the pressure in the PCF. Our devices exhibit a record fringe contrast of 30?dB (visibility of 0.999) due to the ellipsoidal cavity whose surfaces compensate for the diffraction of the reflected beam. The strain sensitivity of the interferometers is higher when the cavities are ellipsoidal than when they are spherical. 相似文献