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A class of Heisenberg models with the orthogonal dimer ground states

Kazuo Ueda·Shin Miyahara
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Abstract

Extensions of the Shastry-Sutherland model are possible in various ways. In particular, it is possible to construct a natural model in three dimensions which has the exact dimer ground state. Recently found spin gap system SrCu_2(BO_3)_2 has this structure. The exchange constants between the layers is expected to be smaller than the intra-layer couplings. However, the exactness of the dimer state for the three dimensional structure is important to understand why magnetic properties of SrCu_2(BO_3)_2 are described well by the two dimensional model.

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Kazuo Ueda, Shin Miyahara. 1999-04-01. A class of Heisenberg models with the orthogonal dimer ground states. https://doi.org/10.1088/0953-8984%2F11%2F17%2F101

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