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arXiv · 2510.14492

Emergent Shastry-Sutherland network from square-kagome Heisenberg antiferromagnet with trimerization

Tomonari Mizoguchi
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Abstract

We study the $S=1/2$ square-kagome lattice Heisenberg antiferromagnet with the trimarized modulation. In the trimerized limit, each trimer hosts the four-fold degenearte ground states characterized by the spin and chirality degrees of freedom. We find that, within the first-order perturbation theory with respect to the inter-trimer coupling, the effective Hamiltonian is the Kugel-Khomskii-type model on a Shastry-Sutherland lattice. Based on a mean-field decoupling, we propose a dimer-covering ansatz for the effective Hamiltonian; however, the validity of these states in the low-energy sector remains an open question.

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Tomonari Mizoguchi. 2025-10-16. Emergent Shastry-Sutherland network from square-kagome Heisenberg antiferromagnet with trimerization. https://arxiv.org/abs/2510.14492

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