Project/Area Number |
63460034
|
Research Category |
Grant-in-Aid for General Scientific Research (B)
|
Allocation Type | Single-year Grants |
Research Field |
固体物性
|
Research Institution | Tokyo University of Science |
Principal Investigator |
MISU Akira Science University of Tokyo, Faculty of Science, Professor, 理学部, 教授 (30011513)
|
Co-Investigator(Kenkyū-buntansha) |
KOBAYASHI Masaaki Science University of Tokyo, Faculty of science, Assistant, 理学部, 助手 (60084323)
|
Project Period (FY) |
1988 – 1990
|
Project Status |
Completed (Fiscal Year 1991)
|
Budget Amount *help |
¥6,600,000 (Direct Cost: ¥6,600,000)
Fiscal Year 1990: ¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1989: ¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1988: ¥2,500,000 (Direct Cost: ¥2,500,000)
|
Keywords | Bismuth-Substituted Iron Garnet / Faraday Rotation / Magneto-Modulation spectroscopy / Reflection type Polarizer / 三回反射型偏光子 / 磁気変調反射率分光 / YIG / ビスマス置換型希土類鉄ガ-ネット / ファラデ-回転 / 磁場変調分光 / コットンムートン効果 / ビスマス置換ガドリニウム鉄ガーネット / 真空紫外反射率 / 磁場変調反射率 |
Research Abstract |
Bismuth ion play an important role in Bi-substituted rare-earth iron garnets which show large Faraday rotation in the visible and near infrared. Reflectivity spectra and magneto-modulation reflectivity spectra of these compounds were studied in vaccum ultraviolet region up to 35 eV using shynchrotron Radiation. There are many structures in this region, for example, at about 4.5, 5.6, 6.3 and 7.6 in the reflectivity spectrum are the electron transfere from 0^<-2> ions to Fe^<3+> ions. A broad peak found at about 18 eV is the 3d-4p transition of Fe^<3+> ion. In a high energy part, we found five structures in the photon energy 23 to 33 eV. The corresponding magneto-modulation spectra of those structures showed dispersion type and also changed their sign at below the compensation temperature comparison with those measured at above this temperature. Those structures are assigned to the 5d-6p transition of Bi^<3+> ions. In conclusion, the Cotton-Mouton effect of Bi^<3+> ions in bismuth-substituted rkreearth iron garnet was observed in spite of ts no-magnetic nature. Optical allowed transition energies of the 5d-6p transition were calculated. The spin-robit interaction, the Coulomb and exchange interactions of a free Bi and a crystal field of cubic symmetry taken into account. This results of calculations are in good agreement with the observed position of the structures. It is concluded that the structures around at 29 eV are the 5d-6p transitions of Bi^<3+> ions and that the 6p states are analogous to those of free Bi ions.
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