| Project/Area Number |
14540358
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
物性一般(含基礎論)
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| Research Institution | Kobe University |
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Principal Investigator |
KABURAGI Makoto Kobe University, Department of Cross-Cultural Studies, Professor, 国際文化学部, 教授 (40093504)
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| Co-Investigator(Kenkyū-buntansha) |
KANG Min Kobe University, Department of Cross-Cultural Studies, Assistant Professor, 国際文化学部, 助教授 (60290425)
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| Project Period (FY) |
2002 – 2004
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| Project Status |
Completed (Fiscal Year 2004)
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| Budget Amount *help |
¥2,800,000 (Direct Cost: ¥2,800,000)
Fiscal Year 2004: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 2003: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2002: ¥1,100,000 (Direct Cost: ¥1,100,000)
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| Keywords | Computational physics / Low dimesinal quantum spin system / Frustrated spin system / chiral phase / Exact diagnalzation / DMRG / Modified spin wave |
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| Research Abstract |
We have found by the DMRG method that a novel chiral phases exist in the XY region of the frustrated XXZ Heisenberg spin chain. The main purpose of this research project is to clarify 1)the existence region in the parameter space of the Hamiltonian, 2)the mechanism of appearance of the chiral phases, 3)properties of the excited states of the chiral phases and 4)magnetization process of the chiral phase. To establish the physical picture of the chiarl phases, we have done the followings;
1.Confirmation by Monte Calro simulation at finite temperatures of the appearance of the modulated phases which correspond to the chiral phases Tin the two dimensional classical frustrated system, the BEG model;
2.Analysis of the impurity spin effect on the spin-1 antiferromagnetic Heisenberg chain by variational method using the matrix product wave functions
3.Analysis of the magnetization process of an Ising-type frustrated S=1 spin chain
4.Analysis of the ground state phase diagrams of an anisotropic spin-(1/2) delta-chain with ferro- and antiferromagnetic interactions
5.Application of modified spin wave theory to ferromagnetic spin chain with arbitrary range interactions.
From these studies, we have established that 1)the chiral phase is essentially same as the physical picture of classical modulated phases ; 2)the canted phase similar to the chiral phase exists in an anisotropic spin-(1/2) delta-chain with ferro- and antiferromagnetic interactions. The DMRG and exact diagonalization program packages for these systems will open for public after improvement of algorithm.
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