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Bond-Operator Mean Field Theory for the Bilayer Heisenberg Model

Yasuhiro Matsushita·Martin P. Gelfand·Chikara Ishii
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Abstract

Bond-operator mean field equations for the square-lattice, S=1/2 bilayer Heisenberg model are developed and solved numerically. In the vicinity of both the zero-field critical point and the field-induced transitions, comparisons are made with T=0 and finite-temperature strong coupling expansions. The mean-field theory suggests that the quantum critical region for the field-induced transitions is restricted to significantly lower temperatures than one might have concluded based on strong-coupling expansions or other numerical studies.

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Yasuhiro Matsushita, Martin P. Gelfand, Chikara Ishii. 1998-10-26. Bond-Operator Mean Field Theory for the Bilayer Heisenberg Model. https://doi.org/10.1143/jpsj.68.247

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