Analysis of molecular elastic response using radiation pressure induced capillary wave

在这个研究项目中，我们提出了一种新的方法，使精确和无损地测量气/液和液/液界面的表面张力和聚合物-分子组装的弹性响应成为可能。在该方法中，毛细波(表面弹性波)是由激光干涉条纹的辐射力引起的。用电光调制器扫描干涉条纹，可以在表面张力与调制频率之间的共振条件下增强毛细管波。然后，利用探测激光的衍射光强检测出共振表面波。这种方法是基于我们最初的想法，但遗憾的是，这种方法在目前的研究阶段还没有得到实验验证。这是由于与辐射力相关的未知现象，这给利用辐射力提高测量技术的准确性带来了很大的问题。一个例子是激光与其在界面上的反射之间的干涉引起的辐射力的复杂分布。因此，我们研究了界面附近的辐射力，并成功地对复杂的力分布进行了精确的分析，并阐明了这一现象的起源。这一结果将为激光操控领域的研究带来突破。此外，我们还成功地分析了微球腔中掺杂分子之间的增强能量传递过程。这是光子与分子强耦合场的演示实验之一。结果表明，只有将反应物掺杂到聚合物、玻璃和液体微球中，才能很容易地增强光反应过程。

In this research project, we proposed a new method that made it possible to precisely and nondestructively measure surface tensions of air/liquid and liquid/liquid interfaces and elastic responses of polymer-molecule assemblies. In the method, the capillary wave (surface elastic wave) is induced by radiation forces of laser interference fringes. And, with scanning the interference fringes with an electro-optical modulator, the capillary wave can be enhanced under the resonance condition between the surface tension and modulation frequency. Then, the resonated surface wave is detected by diffraction intensity of probing laser. This method is based on our original idea.Unfortunately, the experimental verification of this method has not been achieved in the present research term. This is due to the unknown phenomena related to radiation forces, which makes big problems in improving the accuracy of measurement techniques using radiation forces. One example is complicated distribution of radiation forces caused by the interferences between laser light and its reflection at interfaces. Therefore, we investigated the radiation forces in the vicinity of the interfaces, and we succeeded in precise analysis of complicated force distribution and in elucidating the origin of this phenomenon. This results will brings a breakthrough in the fields of laser manipulation researches.In addition, we also succeeded in analyzing the enhanced energy transfer processes between molecules doped in microspherical cavities. This is one of the demonstrational experiments of the strong coupling fields between photons and molecules. The result indicates that photo-reaction processes can be easily enhanced only by doping the reactants into polymer, glass, and liquid microspheres.