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arXiv · 2611.03842

Possibility of Potts Spin-Ice in Rare Earth Twisted-Kagome Layers: an Example of DyAgGe

Gunnar F. Schwertfeger·Po-Hao Chang·Predrag Nikolic·Igor I. Mazin·Hari Bhandari·Nirmal J. Ghimire
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Abstract

Three-dimensional (3D) spin-ice compounds, predominantly based on the pyrochlore or spinel structure, have been attracting considerable interest in the last two decades. A two-dimensional (2D) analogue is the spin-ice consisting of kagome planes. So far, only Ising spin ice has been discovered in any material, and only one 2D material, the kagome compound HoAgGe, has been identified as a spin ice. In this Letter, we show that another rare-earth twisted Kagome magnetic compound, DyAgGe, is in fact a Potts spin ice (or color ice), where at each site not two but four spin directions are allowed. We argue that an 8-state spin ice may also exist in this class of systems. We present a first-principles calculation of magnetic interactions in DyAgGe, and confirm the 4-state Potts structure of this material by matching our model predictions with the available experimental data.

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Gunnar F. Schwertfeger, Po-Hao Chang, Predrag Nikolic, Igor I. Mazin, Hari Bhandari, Nirmal J. Ghimire. 2026-11-02. Possibility of Potts Spin-Ice in Rare Earth Twisted-Kagome Layers: an Example of DyAgGe. https://arxiv.org/abs/2611.03842

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