| Project/Area Number |
62460028
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
固体物性
|
|---|
| Research Institution | Nagoya University |
|---|
Principal Investigator |
ADACHI Kengo Faculty of Science, Nagoya Univ., 理学部, 教授 (40022991)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
MATSUI Hisayuki Faculty of Engineering, Nagoya Univ., 工学部, 助手 (00023185)
SATO Noriaki Collego of General Education, Nagoya Univ., 教養部, 助手 (30170773)
MAMIYA Takayoshi Faculty of Science, Nagoya Univ., 理学部, 教授 (20022600)
IWAHASHI Katsutoshi Faculty of Science, Nagoya Univ., 理学部, 助手 (40022602)
KONTANI Masaaki Faculty of Science, Nagoya Univ., 理学部, 助教授 (90022623)
|
|---|
| Project Period (FY) |
1987 – 1988
|
| Project Status |
Completed (Fiscal Year 1988)
|
| Budget Amount *help |
¥6,900,000 (Direct Cost: ¥6,900,000)
Fiscal Year 1988: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1987: ¥5,900,000 (Direct Cost: ¥5,900,000)
|
|---|
| Keywords | Uranium / Gold / Compound / Stable Phase / Metastable Phase / Heavy Fermion / Dense Kondo / 反強磁性 / 重フエルミオン / 金属間化合物 / 磁性 / 超伝導 |
|---|
| Research Abstract |
In order to make clear the electronic process magnetic and conduction properties of urenium compounds, an intermetallic compound UAu_3 is investigated. This sample from two crystal structures, Cu_3 Ti and Ag_3 Pu types, the former is obtained by a quenching from liquid state and the latter by an annealing of the former.
Electrical resistivity vs. temperature shows a sharp and broad maximum for both phases respectivity, representing the dense Kondo effect. Low temperature specific heat shows an anomaly for both at 10K and 22K respectively, corresponding to the antiferromagnetic transition at T<@D2N@>D2. The coefficient of electronic specific heat estimated from T<T<@D2N@>D2 and T>T<@D2N@>D2, gamma<and gamma> respectively, is given to be gamma<= 100 and gamma>= 280 for Cu<@D23@>D2 Ti phase and gamma<= 105 and gamma>(]sy.simeg[) 800 mJ/K<@D12@>D1. mole for Ag<@D23@>D2Pu, indicating the heavy fermion behavior. The paramagnetic susceptibility above T<@D2N@>D2 for both shows the Curie-Weiss low with the effective moment, mu<@D2eff@>D2 = 3.3 and 3.0 mu<@D2B@>D2 respectively, characterizing a localization of 5f electrons. The magnetization curve up to the field of 60kOe for Cu<@D23@>D2 Ti type shows a metamagnetic behavior below 27K, while that for Ag<@D23@>D2 Pu type accompanies with weak ferromagnetism below T<@D2N@>D2 added to the antiferromagnetic magnetization.
Thus, it is clarified that both UAu_3 phases show the dense Kondo and heavy fermion effects with an antiferromagnetic ordering at low temperature. Further experiment on the single crystal is desirable.
|
