Near-field infrared nanospectroscopy using IR ultra-short pulses

使用红外超短脉冲的近场红外纳米光谱

基本信息

批准号：
11650830
负责人：
INOUYE Yasushi
金额：
$ 0.64万
依托单位：
Osaka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11650830/
关键词：
infrared microspectroscopy near field optics vibrational spectroscopy differential frequency generation ultra short IR pulse 振動分光

项目摘要

We proposed and developed a novel microscopic system for measuring infrared absorption spectra. Higher spatial-resolving capability and signal-to-noise ratio were achieved than those of a conventional system by combining an infrared microscopic system with infrared ultra-short pulses generated by an optically parametric phenomenon. We observed an absorption image of small polystyrene spheres (diameter : 10μm) dispersed on a CaF_2 substrate with IR pulses of 3.4μm which corresponds to C-H stretching vibration mode in polystyrene. Two small spheres adjacent to each other could be discerned, which means that spatial resolution equal to the diffraction limit of the wavelength was achieved. A distinct image of periodic structure of photoresist was also obtained with the IR pulses of 5.8μm which corresponds to C=O stretching vibration mode in an ester bonding.We also studied a possibility of near field infrared microspectroscopy which attains submicron spatial resolution. To realize the super resolving capability in infrared region, we design and fabricated a cantilever having a small aperture at an apex using a silicon micromachine process besides developing an atomic force microscopic system for controlling the cantilever. Then, we built a near field infrared microscope consisting of the IR pulse source, the IR microscope, the cantilevers having a 300-500nm aperture and the AFM module. High optical throughput of 10^<-3> for the near field IR probe was achieved in the system. The throughput was greater than the conventional sharpened-fiber probe by a factor of 10^2. These novel microspectroscopic systems will contribute to observation of dynamics of a single molecule by combining with time-resolved spectroscopic technique.

我们提出并开发了一种用于测量红外抽象光谱的新型显微镜系统。通过将红外显微镜系统与由光学参数性现象产生的红外超短脉冲相结合，与常规系统相比，实现了更高的空间分辨能力和信噪比。我们观察到分散在CAF_2底物上的小聚苯乙烯球（直径：10μm）的抽象图像，其IR脉冲为3.4μm，对应于聚苯乙烯中的C-H拉伸振动模式。可以辨别两个相邻的小球，这意味着实现了相当于波长的衍射极限的空间分辨率。还使用5.8μm的IR脉冲获得了光晶剂的周期性结构的明显图像，该图与酯键合中的C = O拉伸振动模式相对应。我们还研究了达到近场红外微光谱镜的可能性，该微视光镜可以达到近光线的空间分辨率。为了实现红外区域的超级分辨率，我们设计并制造了一个悬臂，除了开发用于控制悬臂的原子力显微镜系统外，还使用了硅微马机过程在顶点处有一个小光圈。然后，我们构建了一个由IR脉冲源，IR显微镜，具有300-500nm光圈和AFM模块的悬臂组成的近场红外显微镜。在系统中实现了近场红外探针的高光学吞吐量。吞吐量大于常规锐化的纤维探针10^2。这些新型的微光谱系统将通过与时间分辨的光谱技术结合使用，从而有助于观察单个分子的动力学。