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1.
光导纤维拉曼光谱技术及其在化学中的应用   总被引:4,自引:1,他引:4  
本文综述了光导纤维拉曼光谱法的研究近况,主要介绍其实验技术及其应用于化学中常规拉曼光谱、表面增强拉曼光谱和近红外富里叶变换拉曼光谱等领域的工作,讨论了该领域存在问题和应用前景.  相似文献   

2.
基于Python语言设计了一款毛细管聚焦的X射线荧光光谱拟合软件QMXRS(quantitative analysis of micro-energy dispersive X-ray fluorescence spectra)并实现其在毛细管聚焦的X射线荧光光谱拟合方面的应用。QMXRS具有小波降噪、本底扣除、能量刻度、元素特征峰的识别、分峰和拟合、能谱的批处理和元素分布成像等功能。毛细管聚焦的X射线荧光分析技术采用毛细管X光透镜对X射线源激发出的X射线束进行聚焦导致X射线荧光光谱分布发生改变。这一变化影响了毛细管聚焦的X射线荧光光谱本底分布。因此QMXRS利用本底预估模型对毛细管聚焦的X荧光光谱本底进行本底分布的修正;同时在全谱拟合过程中,利用半高宽与能量的关系对高斯峰半高宽进行约束,减少高斯峰模型中变量,在保证全谱拟合收敛的同时提高了拟合速度。为验证上述方法的可行性,分别利用QMXRS, PyMca(python multichannel analyzer)和QXAS(quantitative X-ray analysis system)三款软件分析NIST 610标准样品的毛细...  相似文献   

3.
光子自旋霍尔效应是指光束在非均匀介质中传输时,自旋角动量相反的光子在垂直于入射 面的方向发生的横向自旋相关分裂。光子自旋霍尔效应可以和电子自旋霍尔效应作类比:自旋光 子扮演自旋电子的角色,折射率梯度扮演外场的角色。光子自旋霍尔效应源于光的自旋-轨道相互 作用,和两类几何相位有关:一类是动量空间的自旋重定向Rytov-Vlasimirskii-Berry 相位;另 一类是斯托克斯参数空间的Pancharatnam-Berry 相位。光子自旋霍尔效应对物性参数非常敏感, 结合量子弱测量技术,在物性参数测量、光学传感等领域具有重要的应用前景。本文将简单分析 光子自旋霍尔效应的物理根源,回顾近几年不同物理系统中光子自旋霍尔效应的研究进展,介绍 光子自旋霍尔效应在物性参数测量中的应用。最后,展望其在光学模拟运算、显微成像、量子成 像等领域的可能发展方向。  相似文献   

4.
张晓明 《光子学报》2014,43(8):812002
为了解决基于波前或星点图对准大口径空间光学系统时计算量大、面形误差影响大等问题,提出了一种基于离散阵列光源对准空间光学系统的方法.给出了离散阵列光源的设计、检测和标定方法,并以此为基础设计了对准检测光路.以某在研RC望远镜为对象,用离散阵列光源产生参考光,设计了一个用于快速对准主次镜的检测光路.在光学系统设计参数已知的情况下,根据像平面上的点列图,建立了主次镜位置信息和点列图分布信息的函数关系.利用光学设计软件和数学计算工具建立仿真平台,并进行了主次镜的仿真验证.仿真结果表明,使用离散阵列光源可以有效减少计算量,降低面形误差和杂散光的影响,提高对准效率,并且具有较高的计算准确度.  相似文献   

5.
The art of light engineering unveils a world of possibilities through the meticulous manipulation of photonic properties such as intensity, phase, and polarization. Precision control over these properties finds application in a variety of fields spanning communications, light–matter interactions, laser direct writing, and imaging. Terahertz (THz) range, nestled between microwaves and infrared light, stands out for its remarkable ability to propagate with minimal losses in numerous dielectric materials and compounds, making THz imaging a powerful tool for noninvasive control and inspection. In this study, a rational framework for the design and optimal assembly of nonparaxial THz imaging systems is established. The research is centered on lensless photonic systems composed solely of high-resistivity silicon-based nonparaxial elements such as the Fresnel zone plate, the Fibonacci lens, the Bessel axicon, and the Airy zone plate, all fabricated using laser ablation technology. Through a comprehensive examination through illumination engineering and scattered light collection from raster-scanned samples in a single-pixel detector scheme, the imaging systems are evaluated via diverse metrics including contrast, resolution, depth of field, and focus. These findings chart an exciting course toward the development of compact and user-friendly THz imaging systems where sensors and optical elements seamlessly integrate into a single chip.  相似文献   

6.
强脉冲离子束与新材料工艺   总被引:4,自引:0,他引:4  
近几年强脉冲离子束胜材料表面改性和薄摹研究表明,强脉冲能量效应赋予离子束新的物理性质,非常有希望形成高效率、低成本的离子束工艺,为此对脉中功率密度为10^-6--10^9V/cm^2、脉冲宽度〉1μs的强脉冲子束辐照效应强脉冲离子源及其在材料研究中的应用前景进行了评述。  相似文献   

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8.
在物理实验中,将半导体激光器作为光源的实验很多,但由于其光学性能取决于工作电流的大小与谐振腔的质量,所以了解其适用范围,对于指导教学活动是很有帮助的。  相似文献   

9.
The short wavelength of X-rays makes them an excellent choice for probing materials on the nanometer scale and for crystallography of sub-micrometer crystallites. The objective of nanofocusing optics is to produce a small, focused beam size in order to obtain the highest X-ray flux on a small sample or as a fine spatial probe. Achieving nanometer-scale focused X-ray beam sizes puts great demands on the optical elements in an X-ray beamline—the optics must balance the requirements to de-magnify the electron beam X-ray source, to reduce the diffraction-limited focus size, and to minimize the contribution to the focus of aberrations in the optics while collecting the maximum X-ray flux into the focused beam. These requirements dictate that an extreme demagnifying geometry should be employed and that high-specification optical elements must be used. Nanofocusing optics has often been added as an upgrade to existing beamlines at Diamond, extending the range of science that can be carried out. Extreme nanofocusing also forms the basis of new beamlines at Diamond, such as the nanoprobe beamline (I14), which aims to provide sub-30-nm-dimension focused X-ray beams for mapping samples at high spatial resolution. The demand for nanometer-scale diffraction-limited X-ray beams is expected to grow at Diamond and requires corresponding advances in X-ray optics to exploit the present source and future lower emittance storage ring sources; for example, the proposed Diamond II upgrade, projected to give a factor 20 emittance reduction.  相似文献   

10.
李俊昌 《光子学报》2008,37(4):734-739
从统计光学及标量衍射的基本理论出发,研究散射光数字全息重构波面与原散射波的关系,提出非平滑物体双曝光全息过程中散射光传播及干涉的简化模型.基于简化模型及计算机数值计算,对一个双曝光全息干涉系统转动形变的检测过程进行了理论模拟,并通过与该系统实验测量的比较,证实了简化模型的可行性.  相似文献   

11.
We investigate the light scattering through small particles and its applications in nanostructuring, such as nanobumping, nanopatterning and dry laser cleaning. The theoretical calculation based on Mie theory provides an exact solution for sphere cavity resonance and plasmon resonance, which are two mechanisms for dielectric and metallic particles assisted surface nanostructuring in near field. The experimental results indicate that nanobumps on glass surface and subwavelength holes array on silicon surface can be formed without cracks with the self-assembly of 1 μm silica particle mask under laser irradiation. It is also found that the scattering wave by 40 nm gold particles can propagate 200 times away in terms of particle radius as recorded by photoresist under the UV light irradiation. Meanwhile, dry laser cleaning of 40nm gold particle on silicon wafer is demonstrated at plasmonic resonance frequency. The total cleaning efficiency is estimated to be 80%.  相似文献   

12.
耦合模理论及其在光纤光学中的应用   总被引:1,自引:0,他引:1  
首先简要叙述了耦合模理论早期从微波领域逐渐发展起来而延伸到导波光学和其他领域的历程,该理论的数学描述是联立的一阶线性常微分方程组,即耦合模方程.然后明确指出一阶导数形式是该理论的特色,指明该方程在具体的边值问题下严格地与Maxwell方程相等效,并确定其解的主要近似来源与误差量级.最后还扼要叙述了耦合模理论在光纤光学各类问题中的应用,包括建模和模拟.还就使用耦合理论中出现的问题提出了自己的见解.  相似文献   

13.
强调双模厄米多项式在量子光学理论中的地位,认为它是研究连续变量纠缠态和压缩态的必要函数,具有明确的物理意义。利用双模厄米多项式,结合有序算符内的积分技术,给出了若干新的算符恒等式和互逆的积分变换公式,证明了压缩双模粒子数态恰好是双变量厄米多项式激发压缩真空态。  相似文献   

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15.
朱莳通  季沛勇 《光学学报》1997,17(12):677-1680
度规光学中的聚焦定理被导出。给出了光束的聚焦,散焦和陷的条件。讨论了分析在静态曲对称介质中的应用。  相似文献   

16.
The advent of high-brightness X-ray light sources has provided the impetus for the development of focusing systems capable of yielding spatially resolved information from samples at length scales below 10 nm. Beams of such dimensions are fundamental elements in a range of instruments providing powerful analytical tools for a broad range of scientific domains including life, materials, chemical, environmental, and physical sciences. At the ESRF, particular efforts have been made towards the design and implementation of reflective optical systems capable of routine nanoprobe formation at hard X-ray wavelengths (0.1 nm and below) with resolutions in the sub-50 nm range. Often, one of the principal driving forces for the use of such systems is the capacity of reflective optics to deliver very high photon fluxes to the sample. For imaging applications at the ESRF, monochromatic photon fluxes in excess of 108ph/s/nm2 are achievable at energies above 15keV—typically 1–2 orders of magnitude greater than accessible with current alternative technologies. Of course, such performance is not straightforward to achieve and requires considerable care both in the manufacture and implementation of the mirror systems. In this article, we describe some of the technological characteristics and limits of these optics and report on the performance of some of the systems currently in service at ESRF beamlines.  相似文献   

17.
In the modern world, the ability to manipulate and control electromagnetic waves has greatly changed people's lives. Novel optical and electromagnetic phenomena and devices will lead to new scientific trends and techniques in the future. The exploration of new theories of optical design and new materials for optical engineering has attracted great attention in recent years. Transformation optics (TO) provides a new way to design optical devices with extraordinary predesigned functions such as invisibility cloaks and electromagnetic wormholes. As the development of artificial electromagnetic media (e.g. metamaterials and metasurfaces) progresses, many of these novel optical devices designed by TO have been experimentally demonstrated and used in specific applications. Starting from the basic theory of transformation optics, we review its applications, extensions, new branches and recent developments in this paper.  相似文献   

18.
自适应光学与能动光学   总被引:4,自引:0,他引:4  
姜文汉 《物理》1997,26(2):73-79
自适应光学和能动光学是近20年来发展起来的光学新技术,它赋予光学系统以能动可控的能力,为解决困扰光学界几百年之久传统光学技术无法克服动态干扰的老问题,成为高分辨率成像和强激光传输中的关键技术。文章介绍了自适应光学和能动光学原理、技术难点和解决办法。还介绍了我国在激光核聚变和高分辨率天文成像方面应用自适应光学的成果。  相似文献   

19.
激光及其应用   总被引:1,自引:0,他引:1  
从第一台激光器诞生之日起,激光科学技术已经走过了45年的历程.这个45年,是以梅曼1960年发明红宝石激光器作为激光史的起点的.实际上,上世纪50年代,美国汤斯、苏联巴索夫和普罗霍洛夫在微波激射器的实验和利用原子的受激发射进行光放大的理论工作为激光器的发明奠定了具有决定性意义的基础.可以说,这标志着量子电子学的创立.他们因此获得1964年诺贝尔物理学奖.在纪念爱因斯坦1905年提出光量子(简称光子)概念和相对论100周年,2005年被联合国定为世界物理年的时候,  相似文献   

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