| Project/Area Number |
17540331
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Condensed matter physics II
|
|---|
| Research Institution | KYUSHU UNIVERCITY |
|---|
Principal Investigator |
HITAKA Masako Kyushu University, Faculty of Engineering, Research Associate, 大学院工学研究院, 助手 (00264094)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
KAWAE Tatsuya Kyushu University, Faculty of Engineering, Associate Professor, 大学院工学研究院, 助教授 (30253503)
IDOGAKI Toshihiro Kyushu University, Faculty of Engineering, Professor, 大学院工学研究院, 教授 (40038013)
|
|---|
| Project Period (FY) |
2005 – 2006
|
| Project Status |
Completed (Fiscal Year 2006)
|
| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2006: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 2005: ¥2,400,000 (Direct Cost: ¥2,400,000)
|
|---|
| Keywords | spin gap / one-dimensional Heisenberg spin / antiferromagnetic spin chain / low temperature and high field / field induced phase transition / Tomonaga-Luttinger liquid / F_5PNN / DMACuCl_3 / 一次元ハイゼンベルグ系 / 極低温・磁場中比熱測定 |
|---|
| Research Abstract |
We have studied a typical S=1/2 Heisenberg alternating spin chain system ; pentafulorophenyl nitronyl nitroxide (F_5PNN) and a novel magnetic system with two critical field regios ; (CH_3)_2NH_2CuCl_3 (DMACuCl_3) to investigate field induced phase transitions and Tomonaga-Luttinger liquid phase in spin-gapped system.
In F_5PNN, we found a field induced magnetic ordering between Hc1=3T and Hc2=6.5T below T=250mK. Characteristic behaviors are observed depending on the magnetic field up to above Hc2 outside of the H-T phase boundary for the field induced phase. The temperature and field dependence of the specific heat are qualitatively in good agreement with the theoretical calculation on an S=1/2 spin gapped system.
In DMACuCl_3,a spontaneous magnetic ordering is observed below Hc1=2T, while no magnetic ordering is in the 1/2 magnetization plateau field region from Hc1=2T to Hc2 =3.5T. A field induced magnetic ordering emerges above Hc2=3.5T, which grows with increasing magnetic field up to H=8T.
|
