Time-and Space-Resolved Scanning Probe Microscopy Study and Nano Processing.

我们开发了多功能扫描近场光学显微镜(SNOM)系统，可以测量材料的瞬时吸收和激发能量传递，并利用近场光研究了材料的纳米加工过程。1)利用时间分辨扫描近场光学显微镜分析了各种导电聚合物的介观结构。我们发现聚合物的结构强烈地依赖于湿度，并且混合聚合物体系的激发能传递动力学与体系的相分离结构有关。2)研究了导电聚合物对二氧化钛薄膜的电子传递动力学的位置依赖关系。结果表明，热处理的二氧化钛薄膜的电子转移效率最高，与玻璃表面相比，电子转移动力学几乎不依赖于位置，这表明能量迁移和速率分布在…中的重要性3)激发能量传递通过将局域激发与高纳物镜和SNOM系统相结合，构建了时间分辨显微系统来测量激发能量传递的长度依赖关系。4)飞秒瞬时吸收显微光谱和纳米处理首次建立了以白光连续谱为探测脉冲的飞秒吸收显微光谱系统，将未放大的钛宝石激光引入光子晶体光纤中产生白光连续谱。该系统不仅使我们能够在显微镜下测量很弱的10^-7量级的吸收变化，而且还可以应用吸收和荧光SNOM。研制了悬臂式SNOM近场非线性光谱分析系统，阐明了微晶内部的非均匀性。5)半导体纳米粒子和纳米线我们合成了硫化镉和碲化镉纳米粒子和碲化镉纳米线。用皮秒~飞秒激光光谱分析了这些体系的光物理性质。采用再沉淀法和激光烧蚀法合成了有机纳米晶，并用SNOM对其进行了表征。较少

We have developed multifunctional scanning near-field optical microscopy(SNOM) systems that can measure transient absorption and excitation energy transfer, and also examined the nano processing of materials using near-field light.1)Mesoscopic structure of the conductive polymerMesoscopic structures of various conductive polymers were analyzed by time-resolved SNOM. We have found that the structures are strongly dependent on the humidity, and the dynamics of excitation energy transfer in mixed polymer systems have correlated with the phase separation structure of the system.2)The electron transfer to TiO_2Position dependence of the electron transfer dynamics of conductive polymers on TiO_2 thin film was investigated. It was found that electron transfer efficiency on heat-treated TiO_2 thin film was the best one, almost no position dependence on electron transfer dynamics in contrast to the glass surface, suggesting the importance of energy migration and the distribution of the rate con … More stant of electron transfer.3)The excitation energy transferBy combining the local excitation with high NA objective lens and SNOM system, we have constructed the time-resolved microscopy system to measure the length-dependence on the excitation energy transfer.4)Femtosecond transient absorption microspectroscopy and nano processingFemtosecond absorption microspectroscopy system with white-light continuum as a probe pulse was developed for the first time, in which the un-amplified Ti : sapphire laser was introduced into photonic crystal fiber to generate white-light continuum. This system enables us not only to measure very weak absorption change of the order of 10^<-7> under a microscope but also to apply absorption and fluorescence SNOM. Near field nonlinear optical spectroscopy system using cantilever type SNOM is also developed, and heterogeneity inside microcrystals was elucidated. In addition, nano processing of thin microcrystal was demonstrated by near-field light.5)Semiconductor nanoparticle and nanowireWe have synthesized CdS and CdTe nanoparticles and CdTe nanowire. Photophysical properties of these systems were analyzed by picosecond〜femtosecond laser spectroscopy. Organic nanocrystals were also synthesized by reprecipitation and laser ablation methods and characterized by SNOM. Less