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A hidden Goldstone mechanism in the Kagomé lattice antiferromagnet

R. Shankar·D. Shubashree
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Abstract

In this paper, we study the phases of the Heisenberg model on the \kagome lattice with antiferromagnetic nearest neighbour coupling $J_1$ and ferromagnetic next neighbour coupling $J_2$. Analysing the long wavelength, low energy effective action that describes this model, we arrive at the phase diagram as a function of $χ= \frac{J_2}{J_1} $. The interesting part of this phase diagram is that for small $χ$, which includes $χ=0$, there is a phase with no long range spin order and with gapless and spin zero low lying excitations. We discuss our results in the context of earlier, numerical and experimental work.

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R. Shankar, D. Shubashree. 1999-07-26. A hidden Goldstone mechanism in the Kagomé lattice antiferromagnet. https://doi.org/10.1103/physrevb.61.12126

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