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The Néel order for a frustrated antiferromagnetic Heisenberg model: beyond linear spin-wave theory

Qingshan Yuan
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Abstract

Within Dyson-Maleev (DM) transformation and self-consistent mean-field treatment, the Néel order/disorder transition is studied for an antiferromagnetic Heisenberg model which is defined on a square lattice with a nearest neighbour exchange $J_1$ and a next-nearest neighbour exchange $J_2$ along only one of the diagonals. It is found that the Néel order may exist up to $J_2/J_1=0.572$, beyond its classically stable regime. This result qualitatively improves that from linear spin-wave theory based on Holstein-Primakoff transformation.

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Qingshan Yuan. 2001-01-10. The Néel order for a frustrated antiferromagnetic Heisenberg model: beyond linear spin-wave theory. https://doi.org/10.1016/s0375-9601(00)00625-3

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