Theoretical study on the mechanism and dynamics of nanostructure fabrication using localized photons

本研究的目的是(1)从量子理论上建立有限尺寸的准一维材料中由光子、电子极化和声子组成的相互作用系统，并建立一个理论模型，为实验者提供指导信息；(2)预测由于近场效应而产生的集体现象，并将其应用于纳米结构的制备，并阐明纳米制造中的基本过程。如下所述，我们得到了一个理论模型来预测被相干(多)声子覆盖的局域光子，这是相关系统中的固有现象，并对利用局域光子形成纳米点的机制有了定性的理解。第一年，我们用准粒子基础描述了纳米尺度的光学响应，将电子和振动激发与光子放在同等的位置。结果，我们展示了局域光子修饰…的出现更多的是多(相干)声子，这不能由微扰理论驱动，澄清了发生条件。通过对由于掺杂在准一维纳米系统中的杂质引起的光子与声子之间相互作用的反厄米变换，这种光子被局域化在伪一维纳米系统的边缘。阐明了相干声子修饰光子的空间局域化机制，指出在传播远场的情况下，分子与光学近场的光解离可以被禁止的分子振动激发所辅助，并对实验结果中尚未解决的问题进行了一致的解释。最后，我们研究了利用光学近场制备纳米点的沉积过程，找到了控制纳米点尺寸的可能性。所采用的方法不仅从打破光的衍射极限的原理角度来看是独特的和重要的，而且从纳米光子学和纳米加工控制的基础的角度来看也是独特的和重要的。较少

The purpose of the study was (1) to quantum-theoretically formulate an interacting system constituting of photons, electronic polarizations, and phonons in pseudo-one dimensional materials with a finite size, and to build a theoretical model providing experimentalists with guiding information, (2) to predict collective phenomena due to near-field effects, which would be applied to nanostructure fabrication, and to clarify the elemental process in nanofabrication. As described below, we have obtained a theoretical model to predict localized photons dressed by coherent (multiple) phonons, which is inherent phenomenon in the relevant system, as well as qualitative understanding of the mechanism of nanodot formation using localized photons.In the first year, we have formulated optical response at the nanoscale, using a quasiparticle basis, which puts electronic and vibrational excitations on an equal footing with photons. As a result, we showed the occurrence of a localized photon dressed … More by multi-(coherent) phonons, which cannot be driven by a perturbation theory, clarifying the occurrence conditions. Such photons are shown to be localized at the edge of a pseudo-one dimensional nanometric system by anti- Hermitian transformation of the interaction between a photon and a phonon localized due to the impurities doped in the system. Then the mechanism of spatial localization of photons dressed by coherent phonons was clarified, and it followed that molecular photodissociation with optical near fields can be assisted by molecular vibrational excitation forbidden in case of propagating far fields, and that unresolved problems on the experimental results are explained consistently. Finally, we have examined the deposition process of nanodot fabrication with optical near fields to find a possibility of the dot-size control.The approach employed is unique and important not only from the principle viewpoint to break the diffraction limit of light, but also from the viewpoint of foundation for nanophotonics and nanofabrication controlled. Less