搜索结果: 1-15 共查到“光学工程 Raman”相关记录61条 . 查询时间(0.237 秒)
光电信息大讲堂第210期：From discovery of random Raman lasing via natural Rayleigh scattering in ultra-long fibers to unique lasing and sensing features of multimode and multicore fibers with fs-inscribed regular and random 3D refractive-index structures
拉曼光纤激光器 输出光束 折射率光纤
2023/4/17
在二极管泵浦的拉曼光纤激光器的多模渐变折射率光纤中，通过飞秒脉冲刻写FBG，可产生接近衍射极限的输出光束。这一技术已经应用于工业（通信、生物医学、材料加工、基础设施和能源行业）中的各种激光和传感器系统。从超长光纤自然瑞利散射引起的随机拉曼激光的发现出发，主讲人将介绍使用fs脉冲刻写具有规则/随机的3D折射率结构的多模、多芯光纤的技术，以及新型光纤所具有的独特激光和传感性能，这种新型光纤有望在物理上...
Raman-Mie方法反演气溶胶后向散射系数
转动拉曼散射 弹性散射 后向散射系数
2012/12/6
传统的Ｋｌｅｔｔ和Ｆｅｒｎａｌｄ反演气溶胶法依赖于消光系数和后向散射系数的假设关系，给反演结果带来误差。根据纯转动拉曼后向散射系数仅是大气温度和压强的函数，设计的ＲａｍａｎＭｉｅ方法用米散射和纯转动拉曼回波信号结合探空温度和大气压强共同反演气溶胶后向散射系数。不仅消除了Ｋｌｅｔｔ和Ｆｅｒｎａｌｄ方法引入假设带来的误差，还可避免因几何因子修正带来的影响。最后将该方法用于实验室自行研制的拉曼米散射...
Temperature Dependence of the Raman Intensity and the Bandwidth Close to the Order-Disorder Phase Transition in NaNO3
Raman Intensity Bandwidth NaNO3
2013/1/30
We analyze the temperature dependence of the Raman intensity using the experimental data according to a power-law formula close to the order-disorder transition (Tc = 549 K) in NaNO 3. From this analy...
检测了地塞米松磷酸钠和倍他米松磷酸钠两种差向异构体的红外光谱(FTIR), 固体和饱和溶液的常规拉曼光谱(NRS)及以银胶为基底的表面增强拉曼光谱(SERS)。通过红外和拉曼光谱的结合，对其各基团的振动模式进行解析，并对峰进行归属和比较。结果表明：两种物质的主要区别是地塞米松磷酸钠的CH3非对称伸缩振动和对称面内变形振动的拉曼位移较大;依据SERS作用机理和规律，推测两种物质在银胶上主要是通过P—...
研究和发展了一种将微区拉曼(Raman)光谱检测与原子力显微镜(AFM)微纳米扫描成像相结合的新型Raman-AFM技术。设计了Raman光谱与AFM扫描成像的原位检测探头;研制出相应的Raman-AFM系统;利用该系统，对ZnO纳米颗粒和TiO2纳米薄膜开展了微区Raman光谱与微纳米结构的检测实验。研究表明，所获得的Raman光谱检测结果与理论值良好吻合，同时，AFM扫描检测得到的图像很好地表...
合肥上空大气二氧化碳Raman激光雷达探测研究
大气光学 Raman激光雷达 大气CO2体积混合比 合肥
2012/12/12
Raman激光雷达是用于大气成分探测与特性研究的有效工具.介绍了中科院安徽光学精密机械研究所自行研制的一台用于测量低对流层大气CO2时空分布的Raman激光雷达系统,并进行了一系列观测实验和对比分析.系统选用波长355 nm的紫外激光作为光源,利用光子计数卡双通道采集大气中N2和CO2的Raman后向散射信号与Li-7500型H2O/CO2分析仪进行对比标定,通过反演获得了大气CO2水平与垂直方向...
KTP晶体的激光烧蚀特性及Raman光谱研究
KTP晶体 激光烧蚀 激光等离子体 Raman光谱
2012/8/17
高阈值的KTP晶体的研发，对高能激光领域至关重要。采用高重复频率的紫外激光对KTP进行烧蚀，并对烧蚀前后的Raman光谱进行分析，研究发现：激光等离子体效应是造成晶体破坏的主要原因，其逆韧致吸收效应会大大增加激光脉冲能量的沉积，电离效应使得晶体发生充分的离解，高压冲击波效应则把熔化、气化以及电离混合物外排的同时，使得材料发生断裂。烧蚀前后的Raman光谱的特征峰分布基本相同，说明烧蚀作用没有改变K...
Comparison of Optical Fiber Types for All-Raman Systems
Fiber optics communications Fiber optics links subsystems
2015/5/25
We experimentally explore several optical fibers for all-Raman systems. We find that while NZ-DSF with small A eff may require slightly smaller pump power, its OSNR disadvantage is approximately 5 dB ...
Characterization of Short PM Raman Fiber Lasers with a Small Spectral Bandwidth
Characterization Short PM Raman Fiber Lasers Small Spectral Bandwidth
2015/5/20
Linearly polarized Raman fiber lasers using 3 m and 6 m of a novel fiber are discussed. Experimental and theoretical results for output powers at watt levels and spectral widths in the 0.1 nm range ar...
Unrepeatered Transmission over 300 km of NZDSF Using 8x112-Gb/s Time-Interleaved RZ-PDM-QPSK with Coherent Detection and Forward Raman Pumping
Unrepeatered Transmission Coherent Detection RZ-PDM-QPSK
2015/5/15
We show that time-interleaved RZ-PDM-QPSK and forward Raman pumping can increase the performance of a 112-Gb/s PDM-QPSK coherent unrepeatered transmission system over 300 km of NZDSF by more than 2 dB...
AlN纳米线高压相变的Raman光谱特征
AlN纳米线 结构相变 高压Raman光谱
2011/5/17
利用金刚石对顶砧(DAC)技术和显微Raman光谱原位测量技术，在0～33.1 GPa压力范围对AlN纳米线进行了高压相变研究。在24.4 GPa附近，A1(LO)振动模式呈现出较大的非对称性宽化的特征，表明发生了六角纤锌矿到立方岩盐矿的结构转变。岩盐矿结构AlN纳米线的无序声子散射导致了高压相的Raman散射信号。卸压后，高压相的Raman光谱特征被保留下来。根据纤锌矿结构AlN纳米线的振动模式...
High-Density Periodic Arrays of Self-Aligned Subwavelength Nanopyramids for Surface-Enhanced Raman Spectroscopy
High-Density Periodic Self-Aligned Subwavelength Nanopyramids Surface-Enhanced Raman Spectroscopy
2016/12/2
Novel nanotextured surfaces are presented with periodically self-aligned subwavelength nanogroove and nanopyramid structures with precisely defined pitch λg that are closely packed with 2 nm separatio...
40 km long-range Raman-based distributed temperature sensor with meter-scale spatial resolution
Fiber optics sensors Scattering Raman
2015/6/10
We propose a new Raman based distributed measurement technique which allows for temperature sensing over nearly 40 km of graded index multimode optical fiber with meter-scale spatial resolution and te...
Raman Extended GPON using 1240 nm Semiconductor Quantum-Dot Lasers
Fiber optics communications Fiber optics links subsystems
2015/6/9
We present an experimental demonstration of GPON reach extension to 50 km with a 32-way PON split using Raman amplification of the upstream signal with 1240 nm quantum-dot pump lasers.
Enhanced distributed hybrid sensor based on Brillouin and Raman scattering combining Fabry-Perot lasers and optical pulse coding
Fiber optics sensors Scattering Brillouin Scattering Raman
2015/6/8
Pulse coding techniques are proposed in combination with the use of Fabry-Perot lasers for simultaneous strain and temperature sensing based on hybrid spontaneous Raman-Brillouin scattering.Combinatio...