Microscopic Tunneling Theory

通过发展微观和非经验数值模拟得到的针尖-表面系统的电子态分析理论，我们从理论上阐明了原子尺度上的隧穿现象。从第一性原理出发，通过非经验计算得到了富勒烯和有机分子吸附在硅表面的电子态，得到了吸附-表面体系中单个原子的隧穿特性。用共振隧道效应研究了准稳态激发下金属表面上氦束的单态-三态跃迁、脱附激发和价态涨落的形成。发展了适用于强电场、强电流作用下的非平衡系统的第一原理递推传递矩阵法。他已经将其应用于各种尖端-表面系统，例如Al尖端-硅表面。此外，他还了解原子控制的基本机制，即任何表面原子被提取、移动或供应的地方。Makoshi(Himeji Inst.of Technol.)研究表明，共振翻滚模型是理解扫描隧道微球和扫描隧道光谱的物理基础的有力模型。利用杂质的屏蔽库仑势，从理论上研究了半导体表面下体杂质的扫描隧道显微镜图像，阐明了实验中观察到的Friedel振荡的起源。

Developing the theory to analyze the electronic states of tip-surfae system which are obtained by microscopic and non-empirical numerical simulation, we have clarified theoretically the tunneling phenomena in the atomic scale.Yamaguchi (Shizuoka Univ.) has obtained the electronic states of fullerene and organic molecules adsorbed on Si surface by non-empirical calculation from the first principle, and got kowledge of tunnneling characteristics of individual atoms consisting of the adsorbate-surface system.Yoshimori (Okayama Univ.of Sci.) has examined the singlet-triplet transition, the desorption excitation, and the formation of valence fluctuation in the quasi-stably excited He beam on metal surfaces by the resonance tunneling effect.Tsukada (Tokyo Univ.) has developed the first-principle recursion-transfer matrix method which can be applied to the non-equilibrium system under the strong electric field and current. He has applied it to various tip-surface systems, for example, Al tip-Si surface. Furthermore, he has got knowledge of fundamental mechanism of the atom controle where any surface atom is extracted, moved, or supplied.Kitahara (Tokyo Inst.of Technol.) has examined the mechanism of spin-control by evanescent light, and showed that the spin state is changed by the natural fluorescence of light from the excited state.Makoshi (Himeji Inst.of Technol.) has shown that the resonant tummeling model is a powerful model to understand the basis of physics of the scanning tunneling microspope and scanning tunneling spectroscopy.Kobayashi (Ochanomizu Univ.) has theoretically examined, using the screened Coulomb potential of impurity, the image of scanning tunneling microscope of bulk impurities underneath the semiconductor surface, and clarified the origin of Friedel oscillation which is observed in the experiment.