| Project/Area Number |
11640360
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
固体物性Ⅱ(磁性・金属・低温)
|
|---|
| Research Institution | Waseda University |
|---|
Principal Investigator |
KON Keiichiro Waseda University, School of Science and Engineering, Professor, 理工学部, 教授 (40063656)
|
|---|
| Project Period (FY) |
1999 – 2001
|
| Project Status |
Completed (Fiscal Year 2001)
|
| Budget Amount *help |
¥3,400,000 (Direct Cost: ¥3,400,000)
Fiscal Year 2001: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 2000: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1999: ¥2,400,000 (Direct Cost: ¥2,400,000)
|
|---|
| Keywords | dielectric anomaly / magnetic transition / frustrated system / ZnCr_2O_4 / ferroelectrics / RMnO_3 / RMn_2O_5 / RFe_2O_4 / 強誘電性 / YFe_2O_4 / YMn_2O_5 / らせん磁性 / うせん磁性 / 磁気短距離秩序 |
|---|
| Research Abstract |
1. We compared the details of dielectric dispersion in LuFe_2O_4 with the prediction of a theoretical model. In addition, we discovered several new phases with different type ordering of Fe^<2+> and Fe^<3+> ions in highly stoichiometric YFe_2O_4, by dielectric measurement, orbital radiation X-ray and electron diffraction studies.
2. We proposed a model of low frequency dielectric dispersion of ZnCr_2O_4 that we found previously, based on the structural fluctuation of antiferromagnetic clusters.
3. From neutron diffraction and Mossbauer effect measurement of YMn_2O_5, the data, we established a model of the magnetic structure and argued a possible origin of small ferroelectric polarization in RMn_2O_5 crystals.
4. We estimated the magnetic arrangement in a few ferroelectric rare earth manganites RMnO_3.
|
