Electronic structure and phonons of low-dimensional metals prepared on crystal surfaces

晶体表面制备的低维金属的电子结构和声子

基本信息

批准号：
16340090
负责人：
ARUGA Tetsuya
金额：
$ 10.3万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2006
项目状态：
已结题

项目摘要

In low-dimensional metals, the effects interactions, such as electron-electron and electron-phonon ones, plays significant roles to give rise to intriguing phenomena such as density waves and superconductivity. Photoelectron spectroscopy provides single-particle spectral functions and hence serves as a powerful technique in low-dimensional physics. The aim of this work was to study electronic properties of low-dimensional structures prepared on surfaces by angle-resolved photoelectron spectroscopy (ARPES) and to study phonon dispersion of such materials by ultrahigh resolution electron energy loss spectroscopy (UREELS), and eventually to reveal the mechanisms of new and interesting phenomena at surfaces. The Fermiology and the temperature dependence of a CDW gap on In/Cu(001) CDW system exhibited weak-coupling-like appearance, which however contradicted with other qualitative characteristics of the phase transition. We therefore measured the critical X-ray scattering during the phase transition. By analyzing the lattice correlation length above the 2D Ising transition and comparing it with the CDW correlation length obtained by ARPES, we have succeeded in categorizing the phase transition to a strong-coupling, long-coherence type, which usually was not known. This is the most significant achievement of this work. We also studied the magnetism of ultrathin Mn-Pd surface alloys and novel phase transition in Bi monolayer on Ag(001) driven by vacancy-configuration entropy. During the latter study, we found a giant Rashba spin-orbit splitting in Bi/Ag(001), which is nearly an order of magnitude larger than those previously known. The study of this phenomenon is currently under way.

在低维金属中，电子-电子和电子-声子等效应相互作用在产生密度波和超导等有趣现象方面发挥着重要作用。光电子能谱提供单粒子光谱函数，因此成为低维物理学中的一项强大技术。这项工作的目的是通过角分辨光电子能谱（ARPES）研究在表面制备的低维结构的电子特性，并通过超高分辨率电子能量损失谱（UREELS）研究此类材料的声子色散，并最终揭示表面新的有趣现象的机制。 In/Cu(001)CDW系统的费米学和CDW能隙的温度依赖性表现出类弱耦合的外观，但这与相变的其他定性特征相矛盾。因此，我们测量了相变过程中的临界 X 射线散射。通过分析二维伊辛跃迁上方的晶格相关长度，并将其与 ARPES 获得的 CDW 相关长度进行比较，我们成功地将相变归类为通常不为人所知的强耦合、长相干类型。这是这项工作最重要的成就。我们还研究了超薄 Mn-Pd 表面合金的磁性以及由空位构型熵驱动的 Ag(001) 上 Bi 单层的新型相变。在后一项研究中，我们在Bi/Ag(001)中发现了巨大的Rashba自旋轨道分裂，这比之前已知的分裂大了近一个数量级。目前对此现象的研究正在进行中。

项目成果

期刊论文数量（20）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Long-period surface structure stabilized by Fermi surface nesting : Cu(001)-(◇20x√<20>)R26.6゜-In

通过费米表面嵌套稳定的长周期表面结构：Cu(001)-(◇20x√<20>)R26.6゜-In

DOI：
发表时间：
2006
期刊：
Phys. Rev. B 73
影响因子：
0
作者：
T.Nakagawa;H.W.Yeom;E.Rotenberg;B.Krenzer;S.D.Kevan;H.Okuyama;M.Nishijima;T.Aruga
通讯作者：
T.Aruga

Anisotropic water chain growth on Cu(110) observed with scanning tunneling

通过扫描隧道效应观察到 Cu(110) 上的各向异性水链生长

DOI：
发表时间：
2006
期刊：
Phys.Rev.Lett. 96
影响因子：
0
作者：
T.Nakagawa;H.W.Yeom;E.Rotenberg;B.Krenzer;S.D.Kevan;H.Okuyama;M.Nishijima;T.Aruga;T.Yamada
通讯作者：
T.Yamada

X-ray Diffraction Study of the Charge-Density-Wave Phase Transition on In/Cu(001)

In/Cu(001)电荷密度波相变的X射线衍射研究