2015 Fiscal Year Final Research Report
Theoretical research on novel quantum states and phenomena induced by magnetic monopoles in pyrochlore materials
Project/Area Number |
24740253
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Research Category |
Grant-in-Aid for Young Scientists (B)
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Allocation Type | Multi-year Fund |
Research Field |
Condensed matter physics II
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Research Institution | Institute of Physical and Chemical Research |
Principal Investigator |
Onoda Shigeki 国立研究開発法人理化学研究所, 古崎物性理論研究室, 専任研究員 (70455335)
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Project Period (FY) |
2012-04-01 – 2016-03-31
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Keywords | 磁性 / 物性理論 / スピン液体 / スピンアイス / トポロジカル絶縁体 |
Outline of Final Research Achievements |
Novel phases and phenomena induced by emergent fictitious monopoles in pyrochlore oxides have been revealed. For quantum spin ice systems where the quantum magentism originates from rare-earth magnetic moments, we have provided theoretical evidence of a continuous crossover from a classical spin ice characterized by localized monopoles to a quantum spin liquid showing quantum dynamics of monopoles. Through analyses of extensive experimental results on a basis of a quantum spin ice model, we have uncovered that Yb2Ti2O7 and Tb2Ti2O7 are located in Higgs-confining ordered phases with Bose-condensed monopoles. Our first-principles calculations have clarified the electronic structures of the paramagnetic semimetal Pr2Ir2O7 and the antiferromagnetic insulator Y2Ir2O7, and shown the conditions of the emergence of Weyl points acting as monopoles in the reciprocal lattice space.
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Free Research Field |
物性理論
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