Development of time-resolved near-field fluorescence spectroscopy and optical control of photodynamics in mesoscopic domains

时间分辨近场荧光光谱的发展和介观域光动力学的光学控制

• 批准号: 07640690
• 负责人: TAMAI Naoto
• 金额: $ 1.66万
• 依托单位: Kwansei Gakuin University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07640690/
• 关键词: mesoscopic system; near-field spectroscopy; single-photon timing; evanescent wave; tapered optical fiber; total internal reflection; 時間分解蛍光分光; メゾスコピック; エバネンセント光

The purpose of the project is to develop a near-field time-resolved fluorescence spectroscopic system with a picosecond temporal and a few tens of nm-spatial resolutions and to investigate a possibility of the control of photochemical reactions in mesoscopic domains. Using this system, photochemical dynamics characteristic in mesoscopic domains can be elucidated as a function of spatial position.1. Picosecond evanescent wave-induced fluorescence spectroscopic system. Single-photon timing system with a excitation of evanescent wave was developed. This system has a temporal resolution of -30 ps and a depth resolution of -20 nm by using a total internal reflection element such as a sapphire. Phase transition of a water-soluble polymer in the solid/aqueous solution interface layr has been achieved reversibly by an evanescent wave of near IR laser, indicating the possibility of the optical control of the physical properties in the interface layr.2. Picosecond scanning near field optical mic … More roscopy (SNOM). A tapered aluminized fiber with a 50-100 nm aperture was coupled with a picosecond mode-locked Nd : YLF laser and scanned by piezoelectric transducers with -nm resoluton. The induced fluorescence and scattered intensity in a transmission mode were detected by a combination of a inverted microscope and a single-photon timing method, which resulted in a temporal resolution of 20-30 ps and a spatial resoluton of 200-300 nm.3. Photodynamics in mesoscopic domains. Fluorescence dynamics of polymer latex particles with well defined seizes (100-300nm diameter) were investigated by picosecond SNOM as a function of position. It was found that the fluorescence decays are almost the same irrespective of particles, whereas position dependence was strongly observed in dye adsorbates on glass plates.In conclusion, we have developed a time-resolved near-field fluorescence spectroscopy system, which allows us to investigate the picosecond dynamics in mesoscopic domains as well as to control the photochemical reactions. Less

该项目的目的是开发一种具有皮秒时间分辨率和几十nm空间分辨率的近场时间分辨荧光光谱系统，并研究控制介观域中光化学反应的可能性。利用该系统，可以阐明介观区域的光化学动力学特性随空间位置的变化.皮秒倏逝波诱导荧光光谱系统。研制了一种以倏逝波为激发源的单光子计时系统。通过使用诸如蓝宝石的全内反射元件，该系统具有约30 ps的时间分辨率和约20 nm的深度分辨率。利用近红外激光的倏逝波实现了水溶性聚合物在固/水溶液界面层的可逆相变，表明了界面层物理性质的光学控制的可能性.皮秒扫描近场光学麦克风 ...更多信息 显微镜检查（SNOM）。将孔径为50-100 nm的锥形渗铝光纤与皮秒锁模Nd：YLF激光器耦合，并用分辨率为-nm的压电传感器进行扫描。透射模式下的诱导荧光和散射强度通过倒置显微镜和单光子计时方法相结合进行检测，时间分辨率为20-30 ps，空间分辨率为200-300 nm.介观光动力学。用皮秒SNOM研究了具有良好捕获能力的聚合物乳胶粒子（直径100- 300 nm）的荧光动力学随位置的变化。结果发现，荧光衰减几乎是相同的颗粒无关，而位置依赖性强烈观察到染料吸附在玻璃plates.In结论，我们已经开发了一个时间分辨的近场荧光光谱系统，这使我们能够调查皮秒动力学在介观域以及控制光化学反应。少

项目成果

A.Shishido: "Distinct Photochemlcal Phase Transition Behabior of Azobenzene Liquid Cystals Evaluated by Reflection-Mode Analysis" J.Phys,Chem.(in Press). (1997)

A.Shishido：“通过反射模式分析评估偶氮苯液晶的独特光化学相变行为”J.Phys,Chem.（出版中）。

N.Tamai: "Second- and Third-Harmonic Generation from Optically Trapped Liquid Crystal Droplet" Jpn.J.Appl.Phys.35. L547-L550 (1996)

N.Tamai：“光学捕获液晶液滴产生二次和三次谐波”Jpn.J.Appl.Phys.35。