Relaxation of Valence Electrons in s-p Electron Semiconductors Studied by Polarized Soft-X-Ray Emission Spectroscopy
| Project/Area Number |
11640306
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
固体物性Ⅰ(光物性・半導体・誘電体)
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| Research Institution | Tohoku University |
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Principal Investigator |
YANAGIHARA Mihiro Res.Inst.for Sci.Meas., Tohoku University, Assoc.Prof., 科学計測研究所, 助教授 (40174552)
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| Project Period (FY) |
1999 – 2000
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| Project Status |
Completed (Fiscal Year 2000)
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| Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2000: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 1999: ¥2,400,000 (Direct Cost: ¥2,400,000)
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| Keywords | soft X-ray emission / core-level excitation / valence electron relaxation / boron nitride / multilayer coating / multilayer grating / polarized emission spectroscopy / チッ化ホウ素 |
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| Research Abstract |
It is well known that sudden generation of a core hole by excitation of a core electron causes various relaxation to outer-shell electrons in f-electron systems such as rare-earth compounds. Yanagihara et al. suggested that the core-hole effect is also present in the s-p electron systems, the valence band of which is hybridized with delocalized s and p orbitals. In layer-structured h-BN, much less π emission was observed for B 1s spectator emission than normal emission. The π emission anomaly was interpreted to result from the π-electron configuration caused by the Coulomb attractive effect of the core hole. The final goal of this study is to verify the core-hole effect in s-p electron systems using polarized soft-X-ray emission spectroscopy. In order to equip for the spectroscopy a Mo/B_4C multilayer coating was deposited on a grating. The diffraction efficiency and the polarizance of the multilayer grating was estimated to be 3.1% and 99.1%, respectively, for 184 eV at an incidence angle of 45゜. Using the spectrometer mounted with the grating B 1s emission from h-BN was measured, and π and σ emission spectra were separately obtained though with a low energy resolution. On the other hand, N 1s emission spectra from h-BN were measured with high resolution, and the π emission anomaly was also observed. The π-electron configuration model also predicts a satellite peak beside the B 1s main peak in X-ray photoelectron spectrum. A small peak was observed in the vicinity of the expected energy. Judging from these results the aim of the present study was almost achieved, though the polarized emission spectroscopy has not been finished. Recently MgB_2 has attracted much interest as a novel superconductor. Its structure is very similar to h-BN.Thus the new spectrometer is expected to contribute in the study of the superconductivity.
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Report
(3 results)
Research Products
(22 results)
