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An Upper Bound for the Spin-Wave Spectrum of the Heisenberg Antiferromagnet

Tsutomu Momoi
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Abstract

We study the spin-wave spectrum of the Heisenberg antiferromagnet on a bipartite lattice. The spin-wave spectrum on a Néel-ordered ground state is bounded as $\varepsilon (k) \le c |k| $, where $c$ gives an upper bound for the spin-wave velocity. In the large-$S$ limit, the upper bound $c$ coincides with the result of the spin-wave theory.

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Tsutomu Momoi. 1994-06-17. An Upper Bound for the Spin-Wave Spectrum of the Heisenberg Antiferromagnet. https://doi.org/10.1143/jpsj.63.2507

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