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Co
Agui, Akane; Mizumaki, Masaichiro*; Asahi, Toru*; Kagomiya, Isao*; Matsumoto, Koji*; Sayama, Junichi*; Morikawa, Tsuyoshi*; Osaka, Tetsuya*
no journal, ,
no abstracts in English
Ogawa, Shuichi*; Takakuwa, Yuji*; Ishizuka, Shinji*; Yoshigoe, Akitaka; Teraoka, Yuden; Mizuno, Yoshiyuki*
no journal, ,
Nitridation reactions of a Ti(0001) surface, induced by supersonic nitrogen molecular beams, were analysed via real-time in-situ photoemission spectroscopy with synchrotron radiation. Surface temperature dependence of nitrogen uptake curves and nitrided chemical bonding states were investigated. The incident energy range of supersonic nitrogen molecular beams was from 0.03 eV to 1.99 eV. Surface temperature was set at 27
C, 200C, and 400C. The photon energy of synchrotron radiation was 668 eV. A photoemission spectrum of N1s peak could be recorded successfully with a period of 26s. Although the N1s photoemission peak was composed of 2 components at 27C and 200C, an additional conponent was needed at 400C.
Imazono, Takashi; Hirono, Toko*; Kimura, Hiroaki*; Saito, Yuji; Muramatsu, Yasuji*; Sano, Kazuo*; Ishino, Masahiko; Koike, Masato
no journal, ,
We have developed crystal-type polarizing elements to evaluate the state of polarization of soft X-ray in the 1-keV region. In our previous study, we have found out that natural muscovite mica is a promising candidate for a reflection-type polarizer at 0.88 keV. The polarization performances of muscovite and fluorophlogopite micas were evaluated by the rotating-analyzer method at the BL23SU beamline, which tuned to the horizontal linear polarization mode, of SPring-8. As the result, fluorophlogopite mica was found to be high efficient reflection-type polarizer having the polarizance of 0.998. Also, using it, the degree of linear polarization of the incident light was determined to be 0.993 at 0.88 keV.
Matsushita, Tomohiro*; Guo, F. Z.*; Agui, Akane; Kato, Yukako*; Matsui, Fumihiko*; Daimon, Hiroshi*
no journal, ,
no abstracts in English
7 at room temperature investigated by means of real-time synchrotron radiation photoelectron spectroscopy; Translational kinetic energy dependence for initial sticking probability and oxygen amount at saturation coverageYoshigoe, Akitaka; Narihiro, Eisuke*; Moritani, Kosuke; Teraoka, Yuden
no journal, ,
We report the translational kinetic energy dependence on initial sticking probability and oxygen amount at saturation coverages for O
/Si(111)-77 system investigated by real-time synchrotron radiation photoelectron spectroscopy. All experiments were performed at surface reaction analysis appratus at BL23SU in SPring-8. The time evolution and feature of O1s photoelectron spectra dramatically changed with increasing the incident energies. We found that the oxygen uptake curves are almost explained by 2nd-order Langmuir adsorption kinetics and we evaluated the initial sticking probability and saturation coverages from curve fitting procedure. In the incident energy ranges from 0.03 to 0.07eV, the trapping-mediated adsorption dynamics is dominat because the initial sticking probability drastically decreased with increasing incident energy in those energy ranges. On the other hand, the initial sticking probability increases with increasing incident energies, thus we concluded that the direct adsorption becomes a dominat process over 0.07eV energy regions where the contribution of the trapping-mediated adsorption is small. The saturation coverage is almost constant upto 0.4eV, however the saturation coverage increases approximately twice times with increasing the incident energy from 0.4 to about 1.7eV. This result indicates that the dissociative adsorption which is never realized at room temperature, progresses due to overcoming the potential energy barrier by incident energy.
Shobu, Takahisa; Mizuki, Junichiro; Konishi, Hiroyuki; Suzuki, Hiroshi; Suzuki, Kenji*
no journal, ,
no abstracts in English
Izumi, Yudai*; Kitada, Tomo*; Kamohara, Masumi*; Kaneko, Fusae*; Matsui, Takahiro*; Nakagawa, Kazumichi*; Tanaka, Masahito*; Agui, Akane; Muro, Takayuki*; Matsushita, Tomohiro*
no journal, ,
no abstracts in English
Kiriyama, Koji; Shiwaku, Hideaki
no journal, ,
Stabilizing methods for vacuum exhaustion units in the optics section of the beamline have been developed on BL11XU at SPring-8. In this study, we especially focus on the vibrations from scroll pumps in the vacuum exhaustion units. Vibration frequencies were measured directly on the scroll pump under multiple conditions. From these measurements the following countermeasures were found to be dramatically effective for restrain on the 30Hz vibration from (1) to use a damper for scroll pump, (2) not to attach the scroll pump to a vacuum unit support but to put it on directly on the floor, and (3) to settle flexible tubes and the scroll pump on the floor. These methods successfully removed the mechanical vibrations of the scroll pumps. As a result, the amplitude of the 30Hz vibration on the monochromator crystals was decreased from 3.310-5mm to 6.210-6mm. The proposed methods in the present study on BL11XU can be applied to the similar vacuum units at the other beamlines.
Al
Fujimori, Shinichi; Okane, Tetsuo; Saito, Yuji; Kobayashi, Keisuke; Fujimori, Atsushi; Yamagami, Hiroshi; Ikeda, Shugo; Matsuda, Tatsuma; Haga, Yoshinori; Yamamoto, Etsuji; et al.
no journal, ,
no abstracts in English
Okajima, Yuka; Matsumura, Daiju; Nishihata, Yasuo; Konishi, Hiroyuki; Mizuki, Junichiro
no journal, ,
The DXAFS system has been constructed in the second optics hatch at BL14B1. Two plane mirrors equipped at BL14B1 to eliminate higher order harmonics, and to make a focus by mechanically-bent devices in order to obtain good XAFS spectra. On the other hand, the mirrors are removed from optical axis over 30 keV. Wide white X-rays from the bending magnet are diffracted by a bent crystal as polychromator, and focused at the sample. The diffracted X-rays has energy band with of 0.5
1.5 keV, since the diffraction angle is different an each point of the polychromator. The X-rays penetrate a sample, and the intensities are measured by the position sensitive detector. These are the polychromator, sample and the position sensitive detector in 
-2position. When we use Si(422) for the diffraction plane of polychromator which is used in a transmission geometry (Laue), Two types of bent condition of crystal can be chosen according to energy range of X-rays: radius of curvature, R = 1000 mm and 2000 mm. The position sensitive detector is CCD camera system. The X-rays are transformed to the visible rays on fluorescence screen, and reach the receiving area of CCD. In this study, the focus size is less than 0.2mm (FWHM), and Pd K-edge (24.348keV) and Pt K-edge (78.395keV) XAFS spectra are obtained within the accumlation time between 1 and 100msec.
Nakai, Tadafumi*; Uno, Hidetaka*; Zhang, Z.*; Tero, Ryogo*; Suzui, Koichi*; Teraoka, Yuden; Yoshigoe, Akitaka; Makinura, Tetsuya*; Murakami, Koichi*; Urisu, Tsuneo*
no journal, ,
A synchrotron radiation beamline has been designed and manufactured at UVSOR facilities in Institute for Molecular Science to achieve high speed etching of Si by simultaneous irradiation of white synchrotron radiation and XeF molecules. A previously-found beamline was modified by a differential pumping system. A new experimental apparatus was manufactured. In that apparatus, a silicon wafer, exposed to XeF molecules sublimated from the solid, was irradiated by the white synchrotron radiation to be etched with a high speed. This high speed etching phenomenon is due to desorption of silicon fluorides formed by a surface reaction of silicon and fluorin atoms from the XeF molecules.
Ishii, Kenji; Tsutsui, Kenji*; Endo, Yasuo*; Toyama, Takami*; Inami, Toshiya; Owada, Kenji; Kuzushita, Kaori*; Hoesch, M.; Tsubota, Masami; Mizuki, Junichiro; et al.
no journal, ,
Resonant inelastic X-ray scattering studies on high-
superconductors Nd
Ce
CuO
and YBaCuO
are presented. In NdCuO and YBaCuO
, which are Mott insulators, an excitation across the Mott gap is observed around 2 eV. The spectral weight of this excitation shifts to higher energy with increasing the momentum transfer and the dispersion of the excitation is larger along the ![$$[pi,pi]$$](/search/images/ERNVY2DJFROHA0K3EQ.gif)
direction than the ![$$[pi,0]$$](/search/images/ERNVY2DJFQYF0JA.gif)
direction. An intraband excitation in the upper Hubbard band emerges in the spectra of electron-doped Nd
Ce
CuO. As a function of the momentum transfer in the CuO plane, the excitation shifts to higher energy up to 2-2.5 eV at the zone boundary, accompanied by an increase of the spectral width. On the other hand, excitations from two inequivalent Cu sites in hole-doped YBaCuO
are distinguished by the momentum dependence and the Mott gap of the CuO chain site is found to be much smaller than that of the CuO plane site.
RuO
thin filmsTerai, Kota; Okane, Tetsuo; Takeda, Yukiharu; Fujimori, Shinichi; Saito, Yuji; Yoshii, Kenji; Kobayashi, Keisuke*; Fujimori, Atsushi
no journal, ,
A pseudobinary alloy of CaMnRuO (CMRO) is interesting because the solid solution CMRO shows a metallic ferromagnetism although both of the end compositions does not show ferromagnetism. We have fabricated the epitaxial CMRO thin films using the pulsed laser deposition (PLD) method, and studied the ferromagnetic moments by soft X-ray absorption magnetic circular dichroism (XMCD) measurements. The XMCD studies indicated that the spin moments of Mn and Ru are aligned in antiparallel directions. We consider that the small total magnetic moment of CMRO results from the cancellation of the Ru spin moment from Mn spin moment.
Hajima, Ryoichi; Nagai, Ryoji; Iijima, Hokuto
no journal, ,
We have conducted design study of an ERL injector for future X-ray light sources. The injector consists of a 500-kV DC gun, a 1.3GHz buncher, 1.3GHz booster cavities.
Okane, Tetsuo; Takeda, Yukiharu; Fujimori, Shinichi; Terai, Kota; Saito, Yuji; Kobayashi, Keisuke*; Fujimori, Atsushi*; Haga, Yoshinori; Yamamoto, Etsuji; Onuki, Yoshichika*
no journal, ,
no abstracts in English
Baba, Yuji; Sekiguchi, Tetsuhiro; Shimoyama, Iwao; Nath, K. G.*
no journal, ,
no abstracts in English
)SiX(X = F, Cl, Br, I, NCO) by measuring polarization dependence of NEXAFS spectraSekiguchi, Tetsuhiro; Baba, Yuji; Shimoyama, Iwao; Nath, K. G.*; Uddin, M. N.*
no journal, ,
The orientation nature of multilayer organosilicon compounds has been investigated by measuring the dependence of the Si K-shell near-edge X-ray absorption fine structures (NEXAFS) on the polarization angle. Two approaches helped to elucidate the orientation mechanism: the substitution effect and the deposition-rate dependence. The orientation angles of Si-X bond axes were obtained for trimethylsilyl halides, (CH)SiX(X = F, Cl, Br, I, NCO), condensed on Cu(111) at a low (82 K) temperature: the angles are 60, 73, 61, 55, and 55 degrees with respect to the surface normal, for X =F, Cl, Br, I, and NCO, respectively. Chloride (X=Cl) produces the most parallel tilt angle. The specific orientation nature of chloride is attributed to its strong dipole moment as well as the regular tetrahedron shape of the molecule. The molecular volumes calculated verify this view. Furthermore, deposition rates are found to greatly influence the growth manner: namely, high deposition rates led to a slightly perpendicular orientation of Si-X bond axis.
Koike, Masato; Ishino, Masahiko; Takenaka, Hisataka*; Hatayama, Masatoshi*; Sano, Kazuo*; Heimann, P. A.*; Gullikson, E. M.*
no journal, ,
no abstracts in English