2006 Fiscal Year Final Research Report Summary
Experimental investigation of quantum phase transition on one-dimensional spin gapped system
Project/Area Number |
17540331
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Condensed matter physics II
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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)
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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)
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Project Period (FY) |
2005 – 2006
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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 |
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.
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Research Products
(12 results)