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تسجيل مستخدم جديدQuantum disorder in the spatially completely anisotropic triangular lattice II: frustrated hard-core bosons
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Philipp Hauke
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Spin liquids occuring in 2D frustrated spin systems were initially assumed to appear at strongest frustration, but evidence grows that they more likely intervene at transitions between two different types of order. To identify if this is more general, we here analyze a generalization of the spatially anisotropic triangular lattice (SATL) with antiferromagnetic XY interactions, the spatially emph{completely} anisotropic triangular lattice (SCATL). This model can be implemented in experiments with trapped ions, ultra-small Josephson junctions, or ultracold atoms in optical lattices. Using Takahashis modified spin-wave theory, we find indications that indeed two different kinds of order are always separated by phases without magnetic long-range order. Our results further suggest that two gapped, magnetically-disordered phases, identified as distinct in the SATL, are actually continuously connected via the additional anisotropy of the SCATL. As these results indicate, this additional anisotropy -- allowing to approach quantum-disordered phases from different angles -- can give fundamental insight into the nature of quantum disordered phases. We complement our results by exact diagonalizations, which also indicate that in part of the gapped non-magnetic phase, chiral long-range correlations could survive.
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Spin liquids occuring in 2D frustrated spin systems were initially assumed to appear at strongest frustration, but evidence grows that they more likely intervene at transitions between two different types of order. To identify if this is more general
, we here analyze a generalization of the spatially anisotropic triangular lattice (SATL) with antiferromagnetic Heisenberg interactions, the spatially emph{completely} anisotropic triangular lattice (SCATL). Using Takahashis modified spin-wave theory, complemented by exact diagonalizations, we find indications that indeed different kinds of order are always separated by disordered phases. Our results further suggest that two gapped non-magnetic phases, identified as distinct in the SATL, are actually continuously connected via the additional anisotropy of the SCATL. Finally, measurements on several materials found magnetic long-range order where calculations on the SATL predict disordered behavior. Our results suggest a simple explanation through the additional anisotropy of the SCATL, which locates the corresponding parameter values in ordered phases. The studied model might therefore not only yield fundamental insight into quantum disordered phases, but should also be relevant for experiments on the quest for spin liquids.
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