2015 Fiscal Year Annual Research Report
Project/Area Number |
13F03802
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Research Institution | The University of Tokyo |
Principal Investigator |
押川 正毅 東京大学, 物性研究所, 教授 (50262043)
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Co-Investigator(Kenkyū-buntansha) |
LAJKO MIKLOS 東京大学, 物性研究所, 外国人特別研究員
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Project Period (FY) |
2013-04-01 – 2016-03-31
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Keywords | トポロジカル相 / 冷却原子系 / SU(N) / 変分モンテカルロ法 / エッジ状態 |
Outline of Annual Research Achievements |
We studied fermions with SU(N) internal degrees of freedom on the triangular lattice. . We showed that, in the presence of a pi/2 artificial gauge field per plaquette, Mott insulating phases of fermions with SU(N) symmetry and one particle per site generically possess an extended chiral phase with intrinsic topological order characterized by a multiplet of N low-lying singlet excitations for periodic boundary conditions, and by chiral edge states described by the SU(N)_1 Wess-Zumino-Novikov-Witten conformal field theory for open boundary conditions. This has been achieved by extensive exact diagonalizations for N between 3 and 9, and by a parton construction based on a set of N Gutzwiller projected fermionic wave-functions with flux pi/N per triangular plaquette. With the recent realization of the Mott-crossover regime in 3D optical lattices with fermionic Ytterbium atoms the prospect for the experimental realization of strongly correlated SU(N) quantum magnetism is becoming bright. Our proposal for triangular lattices builds on ingredients which have been demonstrated separately: the possibility to realize Mott insulators in optical lattices, and to create static artificial gauge fields in an optical lattice (for alkaline atoms). Besides, working with the triangular lattice is a big advantage because the 3-site permutation term is the first and only term to appear to third order perturbation theory starting from the Hubbard model with one particle per site, by contrast to e.g. the square and honeycomb lattice, where they appear at order 4 and 6 respectively.
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Research Progress Status |
27年度が最終年度であるため、記入しない。
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Strategy for Future Research Activity |
27年度が最終年度であるため、記入しない。
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Research Products
(4 results)