1998 Fiscal Year Final Research Report Summary
Structure Phase Transition in PrCu_2
| Project/Area Number |
09640412
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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 | HOKKAIDO UNIVERSITY OF EDUCATION |
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Principal Investigator |
TAKAYANAGI Shigeru Hokkaido University of Education, Sapporo, Education, Professor, 教育学部・札幌校, 教授 (50013529)
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| Co-Investigator(Kenkyū-buntansha) |
SETTAI Rikio Osaka University, Faculty of Science, Associate Professor, 理学部, 助教授 (00251041)
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| Project Period (FY) |
1997 – 1998
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| Keywords | specific heat / phase transition / Jahn-Teller effect / PrCu_2 / pressure effect / quadrupolar interaction |
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| Research Abstract |
Magnetic Field Dependence
We have studied the anisotropic magnetic field dependence on the cooperative Jahn-Teller specific heat in the orthorhombic PrCu_2. With increasing the field, the Jahn-Teller transition temperature increases slightly for the field along a-and c-axes, while it decreases intensively along the b-axis. The phase diagram constructed from the specific heat data are given. The diagram indicates that the magnetic field suppress the Jahn-Teller transition temperature to zero. This phenomenon is explained quantitatively by the molecular field model on the basis of the crystalline electric field, the quadrupolar interaction and Zeeman Hamiltonian.
Pressure Dependence
We have measured the pressure dependence on the cooperative Jahn-Teller specific heat in the or-thorhombic PrCu_2 using a clamp-type pressure-cell. With increasing the pressure, the Jahn-Teller transition temperature increases slightly and but the specific heat peak depresses. At the pressure of 0.8 GPa we have observed an abrupt jump of specific heat near 8K above the Jahn-Teller transition.
The Anisotropic Field Effects of the Nuclear Enhancement Factor
The anisotropic effects has been observed, on the nuclear enhancement factor and the electronic specific heat coefficient on PrCu_2 from the magnetic field dependence of the specific heat below 1 K.
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