レーザーアブレーション機構解明のためのナノ秒形態観察・分光システムと解析法の確立

由于材料与光的相互作用而产生的光物理和光化学现象已引起人们的广泛关注，21世纪被认为是“光的世纪”。我们致力于利用超快光谱、显微光谱、光反应和光学操纵等手段对有机材料，包括薄膜、微晶粉末、聚合物微球等进行研究，发现在高强度激光激发下，材料的形态经常发生变化。这种形态动力学不仅从光物理和光化学的角度来看是非常有趣和重要的，而且对于阐明材料的结构和性质的动力学方面也是非常有趣和重要的。在目前的工作中，我们将迈克尔逊干涉术与纳秒激发和探测激光相结合，发展了纳秒干涉测量。该系统的空间分辨率为20 nm，时间分辨率为10 ns。干涉测量揭示的形态动力学与时间分辨吸收光谱和荧光光谱数据进行了比较和详细的讨论，这开启了分子光科学的一个新阶段。发展一种新的方法--循环多光子吸收建立光热烧蚀机理建立光化学烧蚀机理聚合物薄膜的伸缩动力学聚合物的光分解反应和刻蚀动力学

Photophysical and photochemical phenomena due to interactions of materials with light have received much attention and the 21st century is considered to be "Century of Light". We have devoted our efforts to the studies on organic materials including films, microcrystalline powders, polymer microspheres, and so on by ultrafast spectroscopy, microspectroscopy, photoreaction, and optical manipulation, during which we found that materials often undergo morphological changes due to high intensity laser excitation. This morphological dynamics is very interesting and important not only from photophysical and photochemical viewpoints but also for elucidating the dynamic aspects of structures and properties of materials.In the present work, we have developed nanosecond interferometry by combining Michelson interferometry with nanosecond excitation and probe lasers. The spatial and temporal resolutions of our system are 20 nm and 10 ns, respectively. Morphological dynamics revealed by the interferometry is compared with time-resolved absorption and fluorescence spectroscopic data and considered in detail, which is opening a new stage of molecular photoscience.Development of a new methodologyEstablishment of photothermal ablation mechanism by "cyclic multiphotonic absorption"Establishment of photochemical ablation mechanismExpansion/contraction dynamics of polymer filmPhotodecomposition reaction and etching dynamics of polymers