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arXiv · 2606.09823

Topological Triplons in the Pinwheel Valence Bond Solid on the Kagome Lattice

Laura Calonge-Martínez·Peng Rao·Frédéric Mila·Johannes Knolle
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Abstract

We investigate the triplon excitations of the pinwheel valence-bond-solid phase on the deformed kagome lattice compound Rb2Cu3SnF12. Using bond-operator mean-field theory, we compute the triplon band structure, dynamical structure factor, Berry curvatures and the associated thermal Hall response. We show that the presence of Dzyaloshinskii-Moriya interactions and an external magnetic field are key for endowing triplon bands with nontrivial Chern numbers. We find good qualitative agreement of the low-energy dynamical structure factor with neutron-scattering experiments. An applied magnetic field can isolate the lowest triplon Chern band leading to a tunable thermal Hall conductivity for accessible temperature and field regimes. Our results establish the deformed kagome pinwheel valence-bond solid as a promising platform for topological triplon physics and for observing the associated thermal Hall effect.

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Laura Calonge-Martínez, Peng Rao, Frédéric Mila, Johannes Knolle. 2026-06-08. Topological Triplons in the Pinwheel Valence Bond Solid on the Kagome Lattice. https://arxiv.org/abs/2606.09823

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