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arXiv · 0705.2201

The quantum $J_1$-$J_1'$-$J_2$ spin-1/2 Heisenberg model: Influence of the interchain coupling on the ground-state magnetic ordering in 2D

R. F. Bishop·P. H. Y. Li·R. Darradi·J. Richter
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Abstract

We study the phase diagram of the 2D $J_1$-$J_1'$-$J_2$ spin-1/2 Heisenberg model by means of the coupled cluster method. The effect of the coupling $J_1'$ on the Neel and stripe states is investigated. We find that the quantum critical points for the Neel and stripe phases increase as the coupling strength $J_1'$ is increased, and an intermediate phase emerges above the region at $J_1' \approx 0.6$ when $J_1=1$. We find indications for a quantum triple point at $J_1' \approx 0.60 \pm 0.03$, $J_2 \approx 0.33 \pm 0.02$ for $J_1=1$.

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R. F. Bishop, P. H. Y. Li, R. Darradi, J. Richter. 2007-05-15. The quantum $J_1$-$J_1'$-$J_2$ spin-1/2 Heisenberg model: Influence of the interchain coupling on the ground-state magnetic ordering in 2D. https://doi.org/10.1209/0295-5075/83/47004

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