| Publication Details |
| disnumber: |
7 |
| field: |
|
| disyear: |
2006 |
| researchfield: |
Magnetism |
| proposalnumber1: |
3479 |
| proposalnumber2: |
4710 |
| proposalnumber3: |
5509 |
| spectrometer1: |
4G:GPTAS |
| spectrometer2: |
C1-1:HER |
| spectrometer3: |
T2-2:FONDER |
| proposaltitleJP: |
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| proposaltitleEN: |
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| principalinvestigatorJP: |
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| principalinvestigatorEN: |
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| thesistitleJP: |
フラストレートしたHeisenberg三角格子磁性体CuFeO2の中性子散乱および放射光X線回折による研究 |
| thesistitleEN: |
Studies of Frustrated Heisenberg Triangular Magnet CuFeO2 by Neutron Scattering and Synchrotron X-ray Diffraction |
| authorEN: |
Terada N. |
| authorJP: |
寺田 典樹 |
| affiliationEN: |
Department of Physics, Faculty of Science, Tokyo University of Science |
| affiliationJP: |
東京理科大学理学研究科物理学専攻 |
| field: |
doctor of science |
| universityname: |
Tokyo University of Science |
| abstract: |
ABO2 type materials, which is one of the “triangular lattice antiferromagnet” (TLA) models with delafossite crystal structure, provide a good example of TLA and present an opportunity to study the geometrical frustration. One of the ABO2 TLA model materials, CuFeO2, is of great interest because of the appearance of “dual character” with both quasi-Ising magnetic ground state and Heisenberg magnetic field-induced states, in spite of the orbital singlet Fe 3+ (S = 5/2 , L = 0). Although there were previously a great deal of works for CuFeO2, the origin of the unusual spin behaviors has not been clarified. We conceived, as a way to study the unusual spin behaviors, that disturbing the delicate balance of the competing exchange interactions by substituting nonmagnetic Al3+ for magnetic Fe3+ should retrieve the original Heisenberg spin character of the orbital singlet Fe3+. In this study, therefore, in order to open the way to study the unusual spin behaviors in CuFeO2, we have performed the neutron scattering, magnetization, specific heat, and synchrotron radiation x-ray diffraction (SR-XRD) measurements using slightly diluted CuFe1−xAlxO2 (0 ≤ x ≤ 0.05) single crystals. As the results, we found that the dramatic changes of quasi-Ising to Heisenberg character in magnetic orderings and excitations by a small amount of nonmagnetic impurity; in addition, we have also revealed a “scalene triangle model” crystal lattice distortion for the 4-sublattice ground state of CuFeO2. |
| keywords: |
geometrical frustration, CuFeO2, triangular lattice antiferromagnet, nonmagnetic impurity, spin wave excitation, neutron scattering, synchrotron radiation X-ray diffraction, lattice distortion |
| language: |
English |
| submitflag: |
1 |
| lastmodified: |
2007/01/14 14:50:24 |
| note: |
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| lastmodifiedbyeditor: |
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| degree: |
Doctor/Ph.D |
| dismonth: |
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| showdetailscount: |
441 |
| searchhitcount: |
6287 |