Magnetic properties of surface outermost layrs and adlayrs studied by a spin-polarized metastable-atom beam

自旋极化亚稳原子束研究表面最外层和阿层的磁特性

• 批准号: 04452091
• 负责人: NISHIGAKI Satoshi
• 金额: $ 4.22万
• 依托单位: Kyushu Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04452091/
• 关键词: Metastable deexcitation spectroscopy; Helium metastable atom; Surface electronic structures; Spin polarization; Spin-resolved electron spectroscopy; Semiconductor surfaces

This project has animed at developing a beam source of helium metastable atoms polarized in electronic spin and at applying the source to the analysis of the spin state in surface outermost layrs. The research has progressed behind schedule because of a head-investigator's change of post. In the last year of the project term, we have performed an experiment of spin polarization of metastables as well as a study on the surface electronic using an established metastable deexciation spectroscopy (MDS) Apparatus.(1) We have constructed a source having an excitation chamber equipped with a hollow cathode and a skimmer together with an optical pumping unit for spin polarization. For the latter, circular-polarized photons have been created by passing He discharge light through a linear polarizer and a lambda/4 plate.(2) The electronic structure of Cs plus oxygen co-adsorbed layrs on the Ge (100) surface has been studied by MDS using a 2^3S He^* beam, mainly concerning Cs 6s, O 2p states and DELTA F.It is shown in the MDS spectra that the degree of electron transfer from adsorbed Cs 6s to incoming oxygen at the Ge (001) surface remains incomplete in contrast to a complete charge outflow from the Cs 6s orbitals to oxygen at the Si (001) surface. we have demonstrated by the whole experiment in this project that the MDS can extract very sensitively local density of states at surface outermost layrs.

本项目致力于研制一种电子自旋极化的氦亚稳原子束源，并将其应用于表面最外层自旋态的分析。由于一位首席研究员的职位变动，这项研究的进展落后于预定计划。在项目的最后一年，我们进行了自旋极化的实验，以及使用建立的亚稳去激光谱（MDS）装置的表面电子的研究。(1)我们已经构建了一个源，具有一个激发室配备了一个空心阴极和一个撇除器连同一个光学抽运单元的自旋极化。对于后者，圆偏振的光子已经创建了通过He放电光通过线性偏振器和λ/4板。(2)用2^3S He^* 束，用MDS方法研究了Ge（100）表面Cs+氧共吸附层的电子结构，主要涉及Cs 6s，MDS谱表明，在Ge（001）面上，电子从Cs 6s向氧的转移程度随Ge（001）面上Cs 6s的电子转移程度的增加而增加，而在Ge（001）面上Cs 6s的电子转移程度随Ge（001）面上O 2 p的电子转移程度的增加而增加。与从Cs 6s轨道到Si（001）表面处的氧的完全电荷流出相反，表面保持不完整。我们通过整个实验证明，MDS能很灵敏地提取出表面最外层的局域态密度。

项目成果

K.Yamada and S.Nishigaki: ""Variation of local charge states and the local electrostatic potential during oxygen adsorption on a caesiated Si (100) surface probed with helium metastables and oxygen molecules"" Surface Science. 293. L893-L899 (1993)

K.Yamada 和 S.Nishigaki：“用氦亚稳态和氧分子探测铯化 Si (100) 表面氧吸附过程中局部电荷态和局部静电势的变化”，《表面科学》。

K.Yamada: "Variation of local charge states and the local electrostatic potential during oxygen adsorption on a caesiated Si(100)surface probed with helium metastables and oxygen molecules" Surface Science. 293. L893-L899 (1993)

K.Yamada：“用氦亚稳态和氧分子探测铯化 Si(100) 表面氧吸附过程中局部电荷态和局部静电势的变化”表面科学。

S.Nishigaki: "Interaction of oxygen atoms and alkali metals with Si(100)or Ge(100)surfaces studied with a helium metastable-atom beam" Proc.2nd Intern.Symp.on Advanced Materials. 201-202 (1995)

S.Nishigaki：“用氦亚稳原子束研究氧原子和碱金属与 Si(100) 或 Ge(100) 表面的相互作用”Proc.2nd Intern.Symp.on Advanced Materials。

S.Nishigaki, K.Iga, K.Yamada and M.Naitoh: ""Interaction of oxygen atoms and alkali metals with Si (100) or Ge (100) surfaces studied with a helium metastable-atom beam"" Proc.2nd Intern.Symp.on Advanced Materials, Eds., Y.Bando, M.Kamo, H.Haneda and T.Ai

S.Nishigaki、K.Iga、K.Yamada 和 M.Naitoh：“用氦亚稳原子束研究氧原子和碱金属与 Si (100) 或 Ge (100) 表面的相互作用”Proc.2nd Intern