Atomic-Scale Materials Processing under Strong Gravitational Field

A strong gravitational field causes the changes in composition and structure through sedimentation or displacement of atoms in multi-component condensed matter. We have developed a high-temperature ultracentrifuge to generate a strong acceleration field of even over 1 million (1x106) G, and, for the first time succeeded in realizing the sedimentation of the constitutive solute atoms and aeven isotope atoms in solids or liquids. The changes in composition and crystalline state of various alloys, polymers, and other substances have been investigated. Recently, we started the experiments on compounds and semiconductors with the aims of new materials synthesis and semiconductor control. The chemical reaction, crystal structure change have been found for metallic compound (Bi3Pb7), or covalent compounds (Y1Ba2Cu3O7-x, TiO2, etc.). The impurity control was also examined in semiconductor. In this article, the recent progress and the future prospects for materials processing are described.

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Sedimentation of Impurity Atoms in InSb Semiconductor under a Strong Gravitational Field

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.289-292.319 ◽

2009 ◽

Vol 289-292 ◽

pp. 319-322 ◽

Cited By ~ 2

Author(s):

Yusuke Iguchi ◽

Masao Ono ◽

Satoru Okayasu ◽

Tsutomu Mashimo

Keyword(s):

Gravitational Field ◽

Vapor Deposition ◽

Physical Vapor Deposition ◽

Atomic Scale ◽

Semiconductor Materials ◽

Strong Gravitational Field ◽

Impurity Atoms ◽

Graded Structure ◽

Alloys And Compounds ◽

Crystal Wafer

An atomic-scale graded structure has been formed by sedimentation of substitutional atoms under an ultra-strong gravitational field of 1 million G level in alloys and compounds. In this study, we investigate the sedimentation of impurity atoms in semiconductor materials under a strong gravitational field. High-temperature ultracentrifuge experiments (0.59×106 G, 400°C, 60 hours) have been performed on an InSb single crystal wafer which surface was coated with Ge by means of Physical Vapor Deposition (PVD). It was observed that the penetration depth of diffused Ge atoms under the gravitational field was several times larger than under terrestrial field at the same temperatures.

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Formation of Vanadium Oxide (V-O System) Graded Compounds under Strong Gravitational Field

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.363.164 ◽

2015 ◽

Vol 363 ◽

pp. 164-170 ◽

Cited By ~ 1

Author(s):

Jahirul Islam Khandaker ◽

Makoto Tokuda ◽

Yudai Ogata ◽

Tadao Nishiyama ◽

Tsutomo Mashimo

Keyword(s):

Optical Properties ◽

Gravitational Field ◽

High Temperature ◽

Vanadium Oxide ◽

Condensed Matter ◽

Structure Change ◽

Scattering Method ◽

Composition Change ◽

Electrical And Optical Properties ◽

Strong Gravitational Field

Strong gravitational field induces sedimentation of atoms due to the different body forces acting on respective atoms, and gives a tool for controlling elemental compositions in condensed matter. Vanadium oxide (V-O system) has large contrast in phases like VO, V2O3, VO2, V2O5 etc., and shows the respective interesting diverse electrical and optical properties. We performed a strong-gravity experiment (0.397106G at 400°C for 24 hours) on a V2O5 polycrystal using the high temperature ultracentrifuge to examine the composition change and further the structure change. It was found by the XRD and Raman scattering method that VO2 and V2O3 phases appeared and the amounts were increased, while one of the V2O5 phase decreased gradually along with the increasing gravitational field.

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Formation of atomic-scale graded structure in Se-Te semiconductor under strong gravitational field

Journal of Applied Physics ◽

10.1063/1.2736334 ◽

2007 ◽

Vol 101 (11) ◽

pp. 113502 ◽

Cited By ~ 17

Author(s):

Xinsheng Huang ◽

Masao Ono ◽

Hideto Ueno ◽

Yusuke Iguchi ◽

Takeshi Tomita ◽

...

Keyword(s):

Gravitational Field ◽

Atomic Scale ◽

Strong Gravitational Field ◽

Graded Structure

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Off-axis electron holography applied to the study of interfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100121624 ◽

1992 ◽

Vol 50 (1) ◽

pp. 244-245

Author(s):

J.K. Weiss ◽

M. Gajdardziska-Josifovska ◽

M. R. McCartney ◽

David J. Smith

Keyword(s):

Electric Fields ◽

Resolution Enhancement ◽

Interfacial Structure ◽

Atomic Scale ◽

Bulk Property ◽

Electron Holography ◽

Specimen Thickness ◽

Composition And Structure ◽

Chemical Segregation ◽

Diffraction Effects

Interfacial structure is a controlling parameter in the behavior of many materials. Electron microscopy methods are widely used for characterizing such features as interface abruptness and chemical segregation at interfaces. The problem for high resolution microscopy is to establish optimum imaging conditions for extracting this information. We have found that off-axis electron holography can provide useful information for the study of interfaces that is not easily obtained by other techniques.Electron holography permits the recovery of both the amplitude and the phase of the image wave. Recent studies have applied the information obtained from electron holograms to characterizing magnetic and electric fields in materials and also to atomic-scale resolution enhancement. The phase of an electron wave passing through a specimen is shifted by an amount which is proportional to the product of the specimen thickness and the projected electrostatic potential (ignoring magnetic fields and diffraction effects). If atomic-scale variations are ignored, the potential in the specimen is described by the mean inner potential, a bulk property sensitive to both composition and structure. For the study of interfaces, the specimen thickness is assumed to be approximately constant across the interface, so that the phase of the image wave will give a picture of mean inner potential across the interface.

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Revealing noncollinear magnetic ordering at the atomic scale via XMCD

Scientific Reports ◽

10.1038/s41598-021-82518-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Fridtjof Kielgast ◽

Ivan Baev ◽

Torben Beeck ◽

Federico Pressacco ◽

Michael Martins

Keyword(s):

Ground State ◽

Magnetic Circular Dichroism ◽

Magnetic Moments ◽

Magnetic Ordering ◽

Atomic Scale ◽

Angle Of Incidence ◽

X Ray ◽

First Time ◽

X Ray Absorption ◽

Magnetic Sublattices

AbstractMass-selected V and Fe monomers, as well as the heterodimer $${\text{Fe}}_1{\text{V}}_1$$ Fe 1 V 1 , were deposited on a Cu(001) surface. Their electronic and magnetic properties were investigated via X-ray absorption (XAS) and X-ray magnetic circular dichroism (XMCD) spectroscopy. Anisotropies in the magnetic moments of the deposited species could be examined by means of angle resolving XMCD, i.e. changing the X-ray angle of incidence. A weak adatom-substrate-coupling was found for both elements and, using group theoretical arguments, the ground state symmetries of the adatoms were determined. For the dimer, a switching from antiparallel to parallel orientation of the respective magnetic moments was observed. We show that this is due to the existence of a noncollinear spin-flop phase in the deposited dimers, which could be observed for the first time in such a small system. Making use of the two magnetic sublattices model, we were able to find the relative orientations for the dimer magnetic moments for different incidence angles.

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Atomic Migration Studies with X-Ray Photon Correlation Spectroscopy

Diffusion Foundations ◽

10.4028/www.scientific.net/df.2.73 ◽

2014 ◽

Vol 2 ◽

pp. 73-94 ◽

Cited By ~ 2

Author(s):

Markus Stana ◽

Manuel Ross ◽

Bogdan Sepiol

Keyword(s):

Low Temperatures ◽

Short Range ◽

Short Range Order ◽

Photon Correlation Spectroscopy ◽

Condensed Matter ◽

Correlation Spectroscopy ◽

Atomic Scale ◽

Photon Correlation ◽

X Ray ◽

Amorphous Systems

The new technique of atomic-scale X-ray Photon Correlation Spectroscopy (aXPCS) makesuse of a coherent X-ray beam to study the dynamics of various processes in condensed matter systems.Particularly atomistic migration mechanisms are still far from being understood in most of intermetallicalloys and in amorphous systems. Special emphasis must be given to the opportunity to measureatomistic diffusion at relatively low temperatures where such measurements were far out of reach withpreviously established methods. The importance of short-range order is demonstrated on the basis ofMonte Carlo simulations.

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COMPARATIVE STUDY OF THE COMPOSITION OF ALCOHOL EXTRACTS ARTEMISIA ABSINTHIUM L., ARTEMI-SIA ARMENIACA LAM. AND ARTEMISIA LATIFOLIA LEDEB.

chemistry of plant raw material ◽

10.14258/jcprm.2019013888 ◽

2019 ◽

pp. 165-171

Author(s):

Станислав (Stanislav) Геннадьевич (Gennal'evich) Ржевский (Rzhevsky) ◽

Михаил (Mikhail) Андреевич (Andreevich) Потапов (Potapov) ◽

Хидмет (Hidmet) Сафарович (Safarovich) Шихалиев (Shikhaliyev)

Keyword(s):

Antibacterial Effect ◽

Acid Ethyl Ester ◽

Component Composition ◽

Artemisia Absinthium ◽

Quantitative Content ◽

Pharmacological Studies ◽

Other Substances ◽

Phenolic Derivatives ◽

First Time ◽

Chromatographic Mass

This paper presents the results of a comparative analysis of the component composition of alcohol extracts Artemisia absinthium, Artemisia armeniaca, and Artemisia latifolia, performed by chromatographic mass spectrometry. The components relating to different classes of compounds (including alcohols, esters, phenolic derivatives) have been identified, their relative quantitative content has been established. In the extract of A. absinthium, 14 compounds were identified, in the extract of A. armeniaca – 16 components, in A. latifolia – 11 different compounds The data obtained for the first time on the analysis of the extract of systematically related species of wormwood, Artemisia armeniaca and Artemisia latifolia, indicate that their composition differs significantly, with coincidences only for some components: phytol and hydroquinone are present in all three species studied, while the 3-O-methyl-D-glucose, ortho-dihydroxybenzene and linoleic acid ethyl ester are characteristic only of Artemisia armeniaca and Artemisia latifolia. Among the present compounds identified components having biological activity, including α-d-metilmannofuranozid, exerting an antibacterial effect and biphenyl, thujone, phytol, hydroquinone and some other substances, which is of interest for further pharmacological studies of these species.

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Doppler temperatures from O(<sup>1</sup>D) airglow in the daytime thermosphere as observed by the Wind Imaging Interferometer (WINDII) on the UARS satellite

Annales Geophysicae ◽

10.5194/angeo-20-203-2002 ◽

2002 ◽

Vol 20 (2) ◽

pp. 203-212 ◽

Cited By ~ 16

Author(s):

C. Lathuillère ◽

W. A. Gault ◽

B. Lamballais ◽

Y. J. Rochon ◽

B. H. Solheim

Keyword(s):

Atmospheric Composition ◽

Large Set ◽

Temperature Variations ◽

Data Processing Software ◽

Imaging Interferometer ◽

Composition And Structure ◽

Instruments And Techniques ◽

The Mean ◽

First Time ◽

Good Agreement

Abstract. From 1992 to 1997, the WINDII interferometer on board the UARS satellite acquired a large set of thermospheric data from the O(1D) and O(1S) airglows. We report here for the first time on daytime O(1D) Doppler temperatures obtained with version 5.11 of the WINDII data processing software. Using a statistical analysis of the temperatures independently measured by the two WINDII fields of view, we estimate that the temperature variations larger than 40 K can be considered as geophysical. Comparisons of WINDII temperatures measured during magnetically quiet days with temperatures obtained by the MSIS-90 and DTM-94 thermospheric models show a 100 K bias. We demonstrate, however, that the modeled temperature variations represent very well the mean temperature variation observed by WINDII over 4 years. We also show that the observed latitudinal/local time variation is in very good agreement with the two empirical models. Finally, the temperature variations during a magnetically disturbed day are found to be qualitatively well represented in form by the models, but largely underestimated. The presence of non-thermal atoms and instrument related issues are discussed as possible explanations for the 100 K bias between the WINDII Doppler temperatures and the empirical models.Key words. Atmospheric composition and structure (air-glow and aurora; pressure, density and temperature; instruments and techniques)

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