| Project/Area Number |
63460022
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
固体物性
|
|---|
| Research Institution | TOHOKU UNIVERSITY |
|---|
Principal Investigator |
SAWADA Anju Tohoku Univercity, Faculty of Science, Assoc. Prof., 理学部, 助教授 (90115577)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
GOTO T Tohoku Univ., Research Institute for Scientific Measurements, Assoc. Prof., 科学計測研究所, 助教授 (60134053)
SUZUKI H Tohoku Univ., Faculty of Science, research Physicist., 理学部, 助手 (50004370)
SATOH T Tohoku Univ., Faculty of Science, Assoc. Prof., 理学部, 助教授 (00004424)
IZUYAMA T Tokyo Univ., College of Arts and Science, Prof., 教養学部, 教授 (10012288)
|
|---|
| Project Period (FY) |
1988 – 1989
|
| Project Status |
Completed (Fiscal Year 1989)
|
| Budget Amount *help |
¥6,900,000 (Direct Cost: ¥6,900,000)
Fiscal Year 1989: ¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1988: ¥4,800,000 (Direct Cost: ¥4,800,000)
|
|---|
| Keywords | Solid 3He / Nuclear Spin / Exchange Interaction / First Order Phase Transition / Spin Wave / Melting Pressure / Nuclear Magnetic Order / Nuclear Demagnetization / 固体ヘリウム3 / 核帯磁率 / NMR / 圧力 / 比熱 / 低磁場秩序相 / 高磁場秩序相 / ヘリウム3-4希釈冷凍機 / 核断熱消磁冷凍 / シールド付超伝導マグネット |
|---|
| Research Abstract |
Solid 3He shows interesting nuclear magnetic properties which are particular to the quantum solid. Many experimental results have established that three magnetic phases exist in bcc solid ^3He:a paramagnetic phase (PP) for temperatures higher than lmK, a low field antiferromagnetic phase (LFP) for temperatures lower than lmK, and a high field magnetically ordered phase (HFP) for field greater than 0.4T. The transitions to the LFP from the PP or the HFP have been clarified as first order. However, the order of the HFP-PP transition is still controversial. The cell was cooled by the demagnetization of Cu, 30 moles. The minimum temperature and the heat leak of nuclear stage were 8luK and 48OpW, respectively. This nuclear stage maintains temperature less than 1mK for about two months. The melting pressure of ^3He was measured in magnetic field. The phase transitions of solid ^3He were deter mined by the anomaly of the melting curves during the temperature and the magnetic field sweep. With thus determined B-T phase diagram, the slope of the transition line near the triple point suggests the first order transition of the paramagnetic to the high field phase transition. However, any trace of thelatent heat was not observed within our experimental accuracy. The spin wave velocity in magnetic field was also obtained.
|
