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Spontaneous plaquette formation in the SU(4) Spin-Orbital ladder

M. van den Bossche·P. Azaria·P. Lecheminant·F. Mila
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Abstract

The low-energy properties of the SU(4) spin-orbital model on a two-leg ladder are studied by a variety of analytical and numerical techniques. Like in the case of SU(2) models, there is a singlet-multiplet gap in the spectrum, but the ground-state is two-fold degenerate. An interpretation in terms of SU(4)-singlet plaquettes is proposed. The implications for general two-dimensional lattices are outlined.

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M. van den Bossche, P. Azaria, P. Lecheminant, F. Mila. 2000-06-30. Spontaneous plaquette formation in the SU(4) Spin-Orbital ladder. https://doi.org/10.1103/physrevlett.86.4124

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