Project/Area Number |
05640409
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Research Category |
Grant-in-Aid for General Scientific Research (C)
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Allocation Type | Single-year Grants |
Research Field |
固体物性Ⅱ(磁性・金属・低温)
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Research Institution | FUKUI UNIVERSITY |
Principal Investigator |
AJIRO Yoshitami FUKUI UNIVERSITY,APPLIED PHYSICS,ASSOCIATE PROFESSOR, 工学部, 助教授 (00025438)
|
Project Period (FY) |
1993 – 1994
|
Project Status |
Completed (Fiscal Year 1994)
|
Budget Amount *help |
¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 1994: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1993: ¥1,400,000 (Direct Cost: ¥1,400,000)
|
Keywords | Phase transition / Universality / Phase diagram / Triangular lattice / One-dimensional magnet / Quantum spin / 磁気相転移 / 三角格子反強磁性体 |
Research Abstract |
The purpose of the present research is to elucidate the phase transitions in low dimensional magnetic system, such as frustrated triangular lattice antiferromagnet and quantum spin one-dimensional antiferromagnet.We performed the experimental study on various model substances using nuclear magnetic resonance (NMR), electron spin resonance (ESR), neutron scattering, susceptibity and high field magnetization maeasuments. 1.Triangular lattice antiferromagnet Our precise measurements between 1.4K and 300K under static magnetic fields up to 40 T,occasionally up to 110 T,revealed a rich variety of magnetic phase transitions in the stacked triangular lattice antiferromagnets ABX3 and AMO2, including a novel phase transition which belongs to a new universality class linked to chiral degeneracy.The magnetic field versus temoerature phase diagrams are classified into two types depending on their magnetic antisotropies. 2.Quantum spin system Nonmagnetic groud states due to quantum spin effect were studied for one-dimensional Heisenberg systems.We observed remarkable differneces in the nonmagnetic impurity efect on the Haldane system, spin-Peierls system and alternating linear chain system and disscussed the physical sihnificance of the results.
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