Project/Area Number |
13130203
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Research Category |
Grant-in-Aid for Scientific Research on Priority Areas
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Allocation Type | Single-year Grants |
Review Section |
Science and Engineering
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Research Institution | University of Tokyo (2004) Osaka University (2001-2003) |
Principal Investigator |
KINDO Koichi Univ.Tokyo, ISSP, Professor, 物性研究所, 教授 (20205058)
|
Co-Investigator(Kenkyū-buntansha) |
NARUMI Yasuo Univ.Tokyo, ISSP, Research Assistant, 物性研究所, 助手 (50360615)
TAKEUCHI Tetsuya Osaka Univ., Low Temp. Centr., Research Assistant, 低温センター, 助手 (90260629)
KOBAYASHI Tatsuo Okayama Univ., Fac.Sci, Professor, 理学部, 教授 (80205468)
HAGIWARA Masayuki Osaka Univ., KYOKUGEN, Professor, 極限量子科学研究センター, 教授 (10221491)
SAKAI Toru JAEA, QBSD., Chief Scientist, 量子ビーム応用研究部門, 主任研究員 (60235116)
|
Project Period (FY) |
2001 – 2004
|
Project Status |
Completed (Fiscal Year 2004)
|
Budget Amount *help |
¥115,100,000 (Direct Cost: ¥115,100,000)
Fiscal Year 2004: ¥18,100,000 (Direct Cost: ¥18,100,000)
Fiscal Year 2003: ¥31,700,000 (Direct Cost: ¥31,700,000)
Fiscal Year 2002: ¥31,900,000 (Direct Cost: ¥31,900,000)
Fiscal Year 2001: ¥33,400,000 (Direct Cost: ¥33,400,000)
|
Keywords | high magnetic field / magnetization measurement / magnetization plateau / spin ladder / oxygen molecule / BIP-TENO / 磁化過程 / 交替磁場 / Cu benzoate / 磁場誘起スピンギャップ / ブリーザーモード / Cu pyrimidine / 吸着酸素 / スピンラダー / パルスマグネット / 非磁性基底状態 / 量子スピン / SPring-8 / 超強磁場 / 磁化ジャンプ / 金属-絶縁体転移 |
Research Abstract |
We have developed in this study the magnet system to carry out the magnetization measurement up to 70 T as a usual manner and succeeded in observing various quantum phenomena induced by very high magnetic field. For example, we have succeeded in observation of wholel/4 plateau in BlP-TENO, which has been regarded as an S=1 antiferromagnetic spin ladder material. As the magnetism of this material comes from free radical, spin should be 1/2 but there is large ferromagnetic interaction between the spins that makes two spins resulted spin 1. From a crystal structure analysis, spin 1 form a spin ladder and the interaction between spin 1 is found to be antiferromagnetic from the magnetic measurements at low field. Up to now, high field magnetization measurement has showed that 1/4 plateau begins around 44 T but it is not obvious that the 1/4 plateau exists in this system. The end of 1/4 plateau has been observed for the first time in our study by extending the magnetization measurement up to 70 T and it also allow us to see the whole plateau region, which begins around 44 T and ends around 65 T. Another striking example is a of S=1. Recently, it has become clear that magnetism of the molecule disappears in a different manner as the antiferromagnetic ordering when it is adsorbed into micro-pores of some copper complex materials. We have succeeded in observation of transition from non-magnetic state to magnetic one by applying high field. It is also interesting point that there is no plateau though the S=1 molecules form spin ladder in the materials.
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