| Project/Area Number |
12440101
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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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Ⅱ(磁性・金属・低温)
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| Research Institution | Osaka University |
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Principal Investigator |
KAWARAZAKI Shuzo Osaka University, Graduate of School of Science, Professor, 大学院・理学研究科, 教授 (40028262)
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| Co-Investigator(Kenkyū-buntansha) |
UWATOKO Yoshiya Institute of Solid State Physics, Tokyo University, Associate professor, 物性研究所, 助教授 (40213524)
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| Project Period (FY) |
2000 – 2002
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| Project Status |
Completed (Fiscal Year 2002)
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| Budget Amount *help |
¥14,200,000 (Direct Cost: ¥14,200,000)
Fiscal Year 2002: ¥1,400,000 (Direct Cost: ¥1,400,000)
Fiscal Year 2001: ¥1,400,000 (Direct Cost: ¥1,400,000)
Fiscal Year 2000: ¥11,400,000 (Direct Cost: ¥11,400,000)
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| Keywords | heavy fermion / neutron scanering / high pressure / uniaxial stress / cryogenic system / Ce(Ru,Rh)2(Si,Ge)2 / Uru2Si2 / SDW / Uru_2Si_2 / Ce(RuRh)2(Si, Ge)2 / URu_2Si_2 / 非クランプ式 / 量子相転移 / 高圧実験 / 微少モーメント秩序 |
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| Research Abstract |
In this research project we aimed to make clear, by means of neutron diffraction method, the origin of several magnetic quantum phenomena which appear in the heavy-fermion system under high pressure. For this purpose, we started from developing a cryogenic system for neutron scattering experiment with in situ pressure-tuning mechanism, and have succeed to construct a very efficient system which allow us to repeat measurements quickly and with good accuracy in setting of the pressure.
By using this system, we have studied the response of several Kondo-lattice compounds to hydrostatic pressure, to uniaxial stress and also to the chemical pressure. A highlight of the studies is the discovery of a switching of the regime of the magnetic ordering in the pseudo-binary alloy system Ce(Ru, Rh)2(Si, Ge)2, that is, the switching between the quasi-particle SDW order and the RKKY localized spin order. Another important result is the discovery of a significant hysteresis in the antiferromagnetic order of the URu2Si2 when the uniaxial stress is cycled. This observation has given an essential information to consider the origin of the so-called "hidden order" in this compound.
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