| Project/Area Number |
12640364
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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Ⅱ(磁性・金属・低温)
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| Research Institution | RIKEN (The Institute of Physical and Chemical Research) |
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Principal Investigator |
WATANABE Isao Muon Science Lab., Senior Researcher, ミュオン科学研究室, 先任研究員 (40260195)
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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 |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2002: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 2001: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 2000: ¥1,900,000 (Direct Cost: ¥1,900,000)
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| Keywords | High-Tc Oxides / Muon Spin Relaxation / Stripe Correlations / High-Pressure μSR / 酸化物高温超電導体 / High-Tc / USR / Stripe Correlations / 1 / 8Effect |
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| Research Abstract |
(1) μSR on the high-Tc oxides
In order to investigate the dynamics of the stripe correlations of spins and holes, μSR measurements have been carried out on in the high-Tc oxides of La-, Bi2212- and-systems. It has been found from the non-magnetic impurity dependence on the La-system around the hole concentration of 1/8 per Cu that the dynamical stripes are statically stabilized by a small amount non-magnetic impurities (less than 1%) and destroyed by a large amount non magnetic impurities (more than 1%). From μSR measurements on the La-system around 100 K, the slowing down of the Cu-spin fluctuations that is expected to be caused by the stabilization of the dynamical stripes has been detected. Since the temperature where the stabilization of the Cu-spin fluctuations starts to be observed by the μSR measurement is consistent to the temperature where carriers tend to be localized, our result reveals that the suppression of the Cu-spin fluctuations couples with the localization of carriers.
From μSR measurements on the Bi2212- and Y-systems, it has been found that the Cu-spin fluctuations are anomalously suppressed by a small amount non-magnetic impurities around the hole concentration of 1/8 per Cu. This result suggests the existence of the dynamical stripes in both systems.
(2)High pressure μSR
Design and development works of a high-pressure cell for μSR measurements have been done. CuBe was chosen as the material of the cell. The maximum pressure was designed to be 1 Gpa. The cell was designed to be matched with the existing cryostat. The cell was manufactured and tested using the muon beam with a high momentum. We are planning to use the cell for real experiments after the pressure calibration at low temperatures.
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