A5073929728- Surface and Thin Film Phenomena
- Electron and X-Ray Spectroscopy Techniques
- Advanced Chemical Physics Studies
- Graphene research and applications
- Ion-surface interactions and analysis
- Semiconductor materials and interfaces
- Semiconductor materials and devices
- Quantum and electron transport phenomena
- Topological Materials and Phenomena
- Quasicrystal Structures and Properties
- Physics of Superconductivity and Magnetism
- Advanced Materials Characterization Techniques
- Integrated Circuits and Semiconductor Failure Analysis
- nanoparticles nucleation surface interactions
- Molecular Junctions and Nanostructures
- X-ray Diffraction in Crystallography
- Silicon Nanostructures and Photoluminescence
- Advanced Condensed Matter Physics
- Catalytic Processes in Materials Science
- ZnO doping and properties
- Chemical and Physical Properties of Materials
- X-ray Spectroscopy and Fluorescence Analysis
- Electronic and Structural Properties of Oxides
- Semiconductor Quantum Structures and Devices
- 2D Materials and Applications
Nagoya University
2016-2025
TU Wien
2003
Artificial post-graphene elemental 2D materials have received much attention recently. Especially, stanene, the tin analogue of graphene, is expected to be a robust topological insulator, even above room temperature. We grown epitaxial stanene on Ag(1 1 1) single crystal template and determined its crystalline structure synergetically by scanning tunneling microscopy, high-resolution synchrotron radiation photoemission spectroscopy, advanced first principles calculations. From STM images, we...
While theoretical studies predicted the stability and exotic properties of plumbene, last group-14 cousin graphene, its realization has remained a challenging quest. Here, it is shown with compelling evidence that plumbene epitaxially grown by segregation on Pd1-x Pbx (111) alloy surface. In scanning tunneling microscopy (STM), exhibits unique surface morphology resembling famous Weaire-Phelan bubble structure Olympic "WaterCube" in Beijing. The "soap bubbles" this "Nano WaterCube" are...
The oxidation of the Rh(111) surface at oxygen pressures from ${10}^{\ensuremath{-}10}\text{ }\mathrm{mbar}$ to 0.5 bar and temperatures between 300 900 K has been studied on atomic scale using a multimethod approach experimental theoretical techniques. Oxidation starts steps, resulting in trilayer O-Rh-O oxide which, although not thermodynamically stable, prevents further intermediate pressures. A thick corundum like ${\mathrm{Rh}}_{2}{\mathrm{O}}_{3}$ bulk is formed only significantly...
Large-scale two-dimensional sheets of graphene-like germanium, namely, germanene, have been epitaxially prepared on Ag(111) thin films grown Ge(111), using a segregation method, differing from molecular beam epitaxy used in previous reports. From the scanning tunneling microscopy (STM) images, surface is completely covered with an atom-thin layer showing highly ordered long-range superstructure wide scale. Two types protrusions, named hexagon and line, form (7√7 × 7√7)R19.1° supercell...
Twenty five years after the first theoretical prediction of two-dimensional (2D) honeycomb-like silicon and germanium, now coined silicene germanene, last Group 14 artificial cousin graphene has been synthesized, thus terminating lineage from (2012) to germanene (2014), stanene (2015), finally plumbene (2019). Here, we describe realizations review tantalizing properties these outstanding novel 2D materials.
Highly ordered linear C60 molecular-chain arrays with 2.31-nm interchain spacing (see image) are self-assembled on Ag(111) by using α-sexithiophene (6T) monolayer nanostripes as a molecular surface nanotemplate. The subtle balance between molecule–molecule and molecule–substrate interactions facilitates the assembly of into well-ordered arrays. Supporting information for this article is available WWW under http://www.wiley-vch.de/contents/jc_2296/2007/z700381_s.pdf or from author. Please...
Tunable arrays of C60 linear chains on the α-sexithiophene (6T) bilayer or monolayer surface nanotemplates are formed by careful control delicate balance between intermolecular and interfacial interactions using different experimental conditions, that is, various 6T coverages post-annealing temperatures. The figure shows scanning tunneling microscopy images arrays.
Abstract Group 14 elemental post‐graphene materials receive much attention because of their outstanding properties, typically, as robust 2D topological insulators. Their heterostructures are a main target in view disruptive applications. Here, the realization striking in‐plane lateral between germanene and stanene shown, which sustainable Ge‐ Snbased graphene analogs, but with strong intrinsic spin–orbit coupling. A unique combination atomic segregation epitaxy (ASE) molecular beam (MBE) for...
A new O induced structure on Rh(111) displaying a (2 sqaureroot[3] x 2sqaureroot[3])R30 degrees periodicity with an oxygen coverage of 2/3 has been studied by high resolution core level spectroscopy, scanning tunneling microscopy, and density functional theory. Although favors fcc hollow sites in all other known phases, it occupies both hcp this structure, which cannot be explained pairwise adsorbate repulsion only. Both the (2sqaureroot[3] 2)-3O structures also exemplify that...
The high-resolution soft x-ray photoelectron study of $\text{Heusler}(L{2}_{1})$-type ${({\mathrm{Fe}}_{2∕3}{\mathrm{V}}_{1∕3})}_{100\ensuremath{-}y}{\mathrm{Al}}_{y}$ $(y=23.8\ensuremath{-}25.8)$ alloys directly confirms the correlation between their thermoelectric properties and electronic structures near Fermi level. It shows rigid-band-like shift main $3d$ bands increase intensity at edge with small deviation Al content from stoichiometry, i.e., $y=25.0$. This implies existence pseudogap...
The geometric structure of ultra-thin cerium oxide films on Rh(111), prepared by annealing the metallic at a very low coverage between 0.3 and 1.5 monolayers in an oxygen atmosphere, is investigated using scanning tunneling microscopy (STM), low-energy electron diffraction (LEED), X-ray photoelectron spectroscopy, density functional theory (DFT) calculations. STM image LEED pattern indicate that epitaxially grown as ordered CeO2(111) layers aligned to 110 azimuthal direction Rh(111)....
The single and binary metal films of Pb Sn on Rh(111) have been studied at room temperature by scanning tunneling microscopy (STM), low-energy electron diffraction, Auger spectroscopy. Both are mobile low coverage form commensurate overlayers (4\ifmmode\times\else\texttimes\fi{}4)-Pb $c(2\ifmmode\times\else\texttimes\fi{}4)$-Sn, respectively. From atomically resolved STM images, the atomic arrangements $c(2\ifmmode\times\else\texttimes\fi{}4)$-Sn identified to be hexagonal rectangular...
We have analyzed the structure and composition of first layer an ${\text{Al}}_{72}{\text{Co}}_{16}{\text{Ni}}_{12}$ tenfold surface by means scanning tunneling microscopy (STM), ion scattering spectroscopy (ISS), Auger electron (AES). High-resolution STM images reveal local structures that decagonal symmetry in addition to usual pentagonal surface. This quasicrystal resembles a random tiling instead ideal quasiperiodic tiling. After annealing at $1100\phantom{\rule{0.3em}{0ex}}\mathrm{K}$,...
The evolution of silicon carbide (0001) surface reconstruction upon annealing has been studied by $\text{Si}\text{ }K$-edge near-edge x-ray-absorption fine structure (NEXAFS). With the increase in temperature, fluorescence yield NEXAFS clearly indicates an disorder Si atoms much deeper interior beneath due to out diffusion forming increased vacancies. concentration vacancies epitaxial graphene formed high-temperature SiC is estimated be as high 15% a depth several micrometers. As acceptors...
Isochronal annealing of Au–Ag binary adsorbates at the Si(111) surface temperatures from 200 to 430 °C has been studied by means low energy electron diffraction, Auger spectroscopy, and Rutherford backscattering spectroscopy techniques. It was found that a √3×√3−(Au,Ag) structure formed for 15 min Ag atoms on Si(111)–5×1-Au Au coverages less than 0.60 ML, √3×√3 kept until decreases 0.70 ML down 0.18 due annealing, while initial coverage kept. Furthermore, when atoms, which are more...
An oxide quasicrystal-related structure with dodecagonal clusters and a Ce–Ti–O-(3 × 3) honeycomb superstructure of ultrathin Ce–Ti–O films on Pt(111).
We studied the atomic arrangements and phase diagrams of two-dimensional (2D) Bi-Pb binary films on a Rh(111) surface with low-energy electron diffraction (LEED), scanning tunneling microscopy (STM), Auger spectroscopy. The 2D exhibited incommensurate (4 × 4) LEED patterns any compositional ratio Bi:Pb. Atomically resolved STM images revealed that formed hexagonal, close-packed structures in solid solution alloy. found followed Hume-Rothery rule. interatomic distance decreased linearly from...