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近场光学虚拟光探针的数值分析 总被引:5,自引:4,他引:1
虚拟光探针是基于近场光学隐失场干涉原理产生的一种非实体探针,可以应用于近场光学超高密度存储、纳米光刻、近场光学成像、光谱探测、纳米样品的近场光学操作等领域。本研究采用三维时间域有限差分(FDTD)方法对近场光学虚拟光探针的光场分布特性进行了数值模拟计算和比较,分析了孔的形状、大小及偏振态等因素对虚拟光探针光场分布的影响,研究结果表明虚拟光探针的通光效率较普通的纳米孔径光纤探针提高10^2-10^4倍;其光场分布的中间峰的半峰全宽(即虚拟光探针的尺寸)在一定距离范围内基本保持不变,从而可以解决近场光学系统中纳米间距控制的难题,避免光学头与介质的磁撞。优化虚拟光探针的设计参量能有效的抑制虚拟光探针中的旁瓣。文章还给出了应用虚拟探针实现高密度光存储的原理方案。 相似文献
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近场拉曼光谱技术的发展 总被引:1,自引:0,他引:1
将近场光学技术与拉曼光谱相结合,发展出近场拉曼光谱术。综述了近场拉曼光谱探测技术的发展现状,讨论了近场拉曼光谱术的优点和纳米局域光谱分析能力。对两种常用的探测方法(常规近场光谱探测方法和近场增强拉曼光谱探测方法)进行了比较,并介绍了近场拉曼光谱技术在生物、化学、纳米材料等领域的一些应用。 相似文献
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本文结合近场扫描结构和纳米线-微光纤耦合技术,提出了一种基于硫化镉纳米线/锥形微光纤探针结构的被动近场光学扫描成像系统.该系统采用被动式纳米探针,保留了纳米探针对样品表面反射光的强约束优势.其理论收集效率为4.65‰,相比于传统的金属镀膜近场探针收集效率提高了一个数量级,可有效地提高扫描探针对样品形貌信息的检测能力;而后通过硫化镉纳米线与微光纤之间高效的倏逝场耦合,将检测的光强信号传输到远场进行光电探测,最终实现对目标样品形貌的分析成像,其样品宽度测量误差在7.28%以内.该系统不需要外部激发光路,利用显微镜自身光源进行远场照明,被动扫描探针仅作为样品表面反射光的被动收集系统.本文基于半导体纳米线/锥形微光纤探针的被动式近场光学扫描成像方案,可有效地降低探针的制备难度和目标光场的检测难度,简化扫描成像的结构,为近场光学扫描显微系统之后的发展提供新的思路. 相似文献
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本文结合近场扫描结构和纳米线-微光纤耦合技术,提出了一种基于硫化镉纳米线/锥形微光纤探针结构的被动近场光学扫描成像系统.该系统采用被动式纳米探针,保留了纳米探针对样品表面反射光的强约束优势.其理论收集效率为4.65‰,相比于传统的金属镀膜近场探针收集效率提高了一个数量级,可有效地提高扫描探针对样品形貌信息的检测能力;而后通过硫化镉纳米线与微光纤之间高效的倏逝场耦合,将检测的光强信号传输到远场进行光电探测,最终实现对目标样品形貌的分析成像,其样品宽度测量误差在7.28%以内.该系统不需要外部激发光路,利用显微镜自身光源进行远场照明,被动扫描探针仅作为样品表面反射光的被动收集系统.本文基于半导体纳米线/锥形微光纤探针的被动式近场光学扫描成像方案,可有效地降低探针的制备难度和目标光场的检测难度,简化扫描成像的结构,为近场光学扫描显微系统之后的发展提供新的思路. 相似文献
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基于近场激发与增强的新型多层纳米薄膜结构在非线性光学器件上的应用与发展前景 总被引:2,自引:0,他引:2
传统光学引入了远场衍射的尺度极限。自从提出了近场光学技术以来 ,由于近场扫描光学显微镜 (NSOM)系统的复杂性而使得近扬的引入和利用变得困难。具有多层纳米薄膜结构的超分辨近场结构 (Super RENS)的提出改变了这种局面 ,并在诸如超高密度光学数据存储、近场光刻技术、纳米光子学晶体管等领域获得了重要的应用。围绕Su per RENS技术 ,通过综述它的基本原理、物理机制以及各项应用 ,指出了基于近场激发与增强原理的新型多层纳米薄膜结构在未来非线性光学器件上的应用与发展前景 相似文献
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Tortora P Abashin M Märki I Nakagawa W Vaccaro L Salt M Herzig HP Levy U Fainman Y 《Optics letters》2005,30(21):2885-2887
We apply heterodyne scanning near-field optical microscopy (SNOM) to observe with subwavelength resolution the amplitude and phase of optical fields propagating in several microfabricated waveguide devices operating around the 1.55 microm wavelength. Good agreement between the SNOM measurements and predicted optical mode propagation characteristics in standard ridge waveguides demonstrates the validity of the method. In situ observation of the subwavelength-scale distribution and propagation of optical fields in straight and 90 degrees bend photonic crystal waveguides facilitates a more detailed understanding of the optical performance characteristics of these devices and illustrates the usefulness of the technique for investigating nanostructured photonic devices. 相似文献
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Nonlinear photonic crystals made from polystyrene materials that have Kerr nonlinearity can exhibit ultrafast optical switching when the samples are pumped by ultrashort optical pulses with high intensity due to the change of the refractive index of polystyrene and subsequent shift of the band gap edge or defect state resonant frequency. Polystyrene has a large Kerr nonlinear susceptibility and almost instantaneous response to pump light, making it suitable for the realization of ultrafast optical switching with a response time as short as a few femtoseconds. In this paper, we review our experimental progress on the continual improvement of all-optical switching speed in two-dimensional and three-dimensional polystyrene nonlinear photonic crystals in the past years. Several relevant issues are discussed and analyzed, including different mechanisms for all-optical switching, preparation of nonlinear photonic crystal samples by means of microfabrication and self-assembly techniques, characterization of optical switching performance by means of femtosecond pump-probe technique, and different ways to lower the pump power of optical switching to facilitate practical applications in optical information processing. Finally, a brief summary and a perspective of future work are provided. 相似文献
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Ye Liu Fei Qin Fei Zhou Qing-bo Meng Dao-zhong Zhang Zhi-yuan Li 《Frontiers of Physics in China》2010,5(3):220-244
Nonlinear photonic crystals made from polystyrene materials that have Kerr nonlinearity can exhibit ultrafast optical switching
when the samples are pumped by ultrashort optical pulses with high intensity due to the change of the refractive index of
polystyrene and subsequent shift of the band gap edge or defect state resonant frequency. Polystyrene has a large Kerr nonlinear
susceptibility and almost instantaneous response to pump light, making it suitable for the realization of ultrafast optical
switching with a response time as short as a few femtoseconds. In this paper, we review our experimental progress on the continual
improvement of all-optical switching speed in two-dimensional and three-dimensional polystyrene nonlinear photonic crystals
in the past years. Several relevant issues are discussed and analyzed, including different mechanisms for all-optical switching,
preparation of nonlinear photonic crystal samples by means of microfabrication and self-assembly techniques, characterization
of optical switching performance by means of femtosecond pump-probe technique, and different ways to lower the pump power
of optical switching to facilitate practical applications in optical information processing. Finally, a brief summary and
a perspective of future work are provided. 相似文献
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使用近场光学显微术(scanning near-field optical microscopy, SNOM)研究了ZnO亚微米线端面出射性质,不同空间形貌Ⅱ-Ⅵ族半导体荧光器件光波导特性,二维光子晶体、准晶光子晶体对LED的出射增强作用以及表面等离激元(surface plasmon polariton, SPP)与半导体纳米荧光器件的相互作用,对纳米集成光路中的光源、光波导、光增强三个重要问题做了实验和理论上的分析.研究发现半导体微纳米线端面出射光束的质量与样品的直径有密切关系.通过合理地设计其直径和 相似文献
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使用近场光学显微术(scanning near-field optical microscopy, SNOM)研究了ZnO亚微米线端面出射性质,不同空间形貌Ⅱ-Ⅵ族半导体荧光器件光波导特性,二维光子晶体、准晶光子晶体对LED的出射增强作用以及表面等离激元(surface plasmon polariton, SPP)与半导体纳米荧光器件的相互作用,对纳米集成光路中的光源、光波导、光增强三个重要问题做了实验和理论上的分析.研究发现半导体微纳米线端面出射光束的质量与样品的直径有密切关系.通过合理地设计其直径和
关键词:
纳米集成光路
扫描近场光学显微术
光波导
光增强 相似文献
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Larcheri S Rocca F Pailharey D Jandard F Graziola R Kuzmin A Kalendarev R Purans J 《Micron (Oxford, England : 1993)》2009,40(1):61-65
Investigations of complex nanostructured materials used in modern technologies require special experimental techniques able to provide information on the structure and electronic properties of materials with a spatial resolution down to the nanometer scale. We tried to address these needs through the combination of X-ray absorption spectroscopy (XAS) using synchrotron radiation microbeams with scanning near-field optical microscopy (SNOM) detection of the X-ray excited optical luminescence (XEOL) signal. The first results obtained with the prototype instrumentation installed at the European Synchrotron Radiation Facility (Grenoble, France) are presented. They illustrate the possibility to detect an element-specific contrast and to perform nanoscale XAS experiments at the Zn K and W L(3)-absorption edges in pure ZnO and mixed ZnWO(4)/ZnO thin films. 相似文献
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We report on the development of a cantilever-based scanning near-field optical microscope (SNOM) working in an extreme environment,
at cryogenic temperature around 10 K and under strong magnetic field up to 7 T. We designed a new optical system based on
an infinite conjugate microscope, which extracts the near-field signal from a small aperture through a narrow chamber into
free space as collimated light. Using this system, we successfully measured near-field and topographical images of a metal-hole
sample simultaneously. Combining the local optical accessing technique with the external control of the electronic state,
this SNOM system will be a powerful tool to study optical properties of semiconductor nanostructures. 相似文献
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High resolution optical microscopy has many interesting applications in solid state physics, low temperature physics, biology and semiconductor technology. Unfortunately, the lateral resolution of conventional microscopes is limited by the Rayleigh-limit. “Scanning nearfield optical microscopy” (SNOM) seems to be a promising new approach to characterize the properties of materials optically with a high lateral resolution of 50–100 nm. The most important part of such a microscope is the scanning probe (a special glass fiber tip). However, the quality of the optical fiber tip is of decisive importance. Since the production process of pulled and coated glass fiber tips is still highly empirical and error-prone, a technique would be useful to determine the tips’ quality before they are shipped to the user or mounted in the microscope. The tips’ apertures are smaller than λ/2 and therefore they cannot be measured in a non-destructive way by conventional optical microscopy. This paper discusses an easy and fast method for the optical characterization of common glass fiber SNOM tips. The effective aperture of the tip is measured from the far-field distribution of the emitted intensity recorded by a CCD target. A numerical model is introduced to solve this inverse task and a simple optical setup is presented to detect light emitted by the tip at an angle of up to 90° from the optical axis. Experimental investigation, near/far-field calculations and scanning electron microscope investigations show the working principle of this measurement technique for the analysis and evaluation of a typical nanostructured object. 相似文献