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Adatoms
The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
Yoshiaki Sugimoto – One of the best experts on this subject based on the ideXlab platform.
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role of lateral forces on atom manipulation process on si 111 7 7 surface in dynamic force microscopy
Physical Review B, 2017Co-Authors: Ayhan Yurtsever, Yoshiaki Sugimoto, Masayuki Abe, Seizo MoritaAbstract:We investigated the role of lateral force components on the lateral manipulation of intrinsic Si Adatoms toward a vacancy site on a Si(111)-$(7\ifmmode\times\else\texttimes\fi{}7)$ surface using noncontact atomic force microscopy at room temperature. Lateral atom manipulation was accomplished via constant-height scans using a set of tips with varying chemical reactivities. We determined the vertical and lateral force as well as the interaction energy profiles associated with the lateral manipulation of a Si adatom on a Si(111)-$(7\ifmmode\times\else\texttimes\fi{}7)$ surface. Our results demonstrate that lateral forces do not play a decisive role in the manipulation process while the vertical force component is key for the manipulation process, and the ability to manipulate the Si adatom depends primarily on the chemical nature of the tip apex. Our results further reveal that the tips that exhibit high chemical reactivity with Si Adatoms have a sharper interaction energy profile above Si Adatoms than tips with less chemical reactivity, indicating the stronger atom-trapping ability of the chemically reactive tips. This characteristic property gives tips the ability to create localized reductions in the energy barrier required for adatom movement, thereby enabling thermally induced adatom hopping toward the tip. These findings can enhance our understanding of the underlying mechanisms involved in the lateral manipulation of intrinsic Adatoms of semiconductor surfaces, as well as adsorbate atoms/molecules forming covalent bonds with tip-surface systems, i.e., chemisorption systems.
Takeo Ohsaka – One of the best experts on this subject based on the ideXlab platform.
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enhanced oxidation of aldohexose and aldopentose on hg adatom modified au electrode in alkaline aqueous solution
Electroanalysis, 2005Co-Authors: Futoshi Matsumoto, Masahiro Harada, Nobuyuki Koura, Takeyoshi Okajima, Takeo OhsakaAbstract:The electrochemical behavior of aldohexose and aldopentose monosaccharides was examined on Hg adatom-modified and bare Au electrodes in alkaline aqueous solution using cyclic voltvoltammetry. For the bare Au electrode, the oxidation peak currents are dependent on hydroxyl group configuration on the monosaccharides. On the other hand, for the Hg adatom-modified Au electrode, the actual oxidation peak currents were similar for all monosaccharides other than glucose. Dispersion of Hg Adatoms on the Au surface led to diminishment of configurational differences between monosaccharides as well as enhancement of oxidation peak current.
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Enhanced Oxidation of Aldohexose and Aldopentose on Hg Adatom‐Modified Au Electrode in Alkaline Aqueous Solution
Electroanalysis, 2005Co-Authors: Futoshi Matsumoto, Masahiro Harada, Nobuyuki Koura, Takeyoshi Okajima, Takeo OhsakaAbstract:The electrochemical behavior of aldohexose and aldopentose monosaccharides was examined on Hg adatom-modified and bare Au electrodes in alkaline aqueous solution using cyclic voltvoltammetry. For the bare Au electrode, the oxidation peak currents are dependent on hydroxyl group configuration on the monosaccharides. On the other hand, for the Hg adatom-modified Au electrode, the actual oxidation peak currents were similar for all monosaccharides other than glucose. Dispersion of Hg Adatoms on the Au surface led to diminishment of configurational differences between monosaccharides as well as enhancement of oxidation peak current.
Toshio Ogino – One of the best experts on this subject based on the ideXlab platform.
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Substitution of In for Si Adatoms and exchanges between In and Si Adatoms on a Si(111)-7×7 surface
Physical Review B, 1997Co-Authors: Hiroki Hibino, Toshio OginoAbstract:Substitution of In for Si Adatoms and exchanges between In and Si Adatoms on a Si(111)-7\ifmmode\times\else\texttimes\fi{}7 surface have been investigated using high-temperature (HT) scanning tunneling microscopy (STM). Indium substitution probability depends on the four different types of Adatoms in the 7\ifmmode\times\else\texttimes\fi{}7 reconstruction. Differences in the In substitution energy between different types of Adatoms are estimated from the substitution probability. Adatom exchange rates obtained from sequential HT-STM images are also dependent on the combination of In and Si Adatoms. Measured activation energies and prefactors for exchanges on Si(111)-7\ifmmode\times\else\texttimes\fi{}7 are comparable to those on Si(111)-$\sqrt{3}$\ifmmode\times\else\texttimes\fi{}$\sqrt{3}$. The adatom exchange is not sensitive to the adatom symmetry. HT-STM results on the adatom exchanges on Si(111) suggest that the motion of the metal Adatoms is a rate-limiting step in this process.
Futoshi Matsumoto – One of the best experts on this subject based on the ideXlab platform.
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enhanced oxidation of aldohexose and aldopentose on hg adatom modified au electrode in alkaline aqueous solution
Electroanalysis, 2005Co-Authors: Futoshi Matsumoto, Masahiro Harada, Nobuyuki Koura, Takeyoshi Okajima, Takeo OhsakaAbstract:The electrochemical behavior of aldohexose and aldopentose monosaccharides was examined on Hg adatom-modified and bare Au electrodes in alkaline aqueous solution using cyclic voltammetry. For the bare Au electrode, the oxidation peak currents are dependent on hydroxyl group configuration on the monosaccharides. On the other hand, for the Hg adatom-modified Au electrode, the actual oxidation peak currents were similar for all monosaccharides other than glucose. Dispersion of Hg Adatoms on the Au surface led to diminishment of configurational differences between monosaccharides as well as enhancement of oxidation peak current.
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Enhanced Oxidation of Aldohexose and Aldopentose on Hg Adatom‐Modified Au Electrode in Alkaline Aqueous Solution
Electroanalysis, 2005Co-Authors: Futoshi Matsumoto, Masahiro Harada, Nobuyuki Koura, Takeyoshi Okajima, Takeo OhsakaAbstract:The electrochemical behavior of aldohexose and aldopentose monosaccharides was examined on Hg adatom-modified and bare Au electrodes in alkaline aqueous solution using cyclic voltammetry. For the bare Au electrode, the oxidation peak currents are dependent on hydroxyl group configuration on the monosaccharides. On the other hand, for the Hg adatom-modified Au electrode, the actual oxidation peak currents were similar for all monosaccharides other than glucose. Dispersion of Hg Adatoms on the Au surface led to diminishment of configurational differences between monosaccharides as well as enhancement of oxidation peak current.
Yasuo Cho – One of the best experts on this subject based on the ideXlab platform.
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atomic dipole moment distribution on a hydrogen adsorbed si 111 7 7 surface observed by noncontact scanning nonlinear dielectric microscopy
Applied Physics Letters, 2013Co-Authors: Daisuke Mizuno, Kohei Yamasue, Yasuo ChoAbstract:Noncontact scanning nonlinear dielectric microscopy (NC-SNDM) can atomically resolve the polarization distribution on material surfaces. We observed a hydrogen-adsorbed Si(111)–(7 × 7) surface using NC-SNDM and found that hydrogen-adsorbed Si Adatoms had lower dipole moments than bare Si Adatoms. We discuss the charge distribution around a hydrogen-adsorbed Si adatom in terms of its geometry and the electronegativities of hydrogen and silicon. Our model suggests that the charge distribution around a hydrogen-adsorbed adatom is nearly symmetric and it qualitatively explains the experimental results. We thus conclude that the hydrogen-adsorbed Si Adatoms are both electrically and chemically passivated.