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arXiv · 2505.05889

Topological Devil's staircase in a constrained kagome Ising antiferromagnet

Afonso Rufino·Samuel Nyckees·Jeanne Colbois·Frédéric Mila
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Abstract

We show that the constrained Ising model on the kagome lattice with infinite first and third neighbor couplings undergoes an infinite series of thermal first-order transitions at which, as in the Kasteleyn transition, linear defects of infinite length condense. However, their density undergoes abrupt jumps because of the peculiar structure of the low temperature phase, which is only partially ordered and hosts a finite density of zero-energy domain walls. The number of linear defects between consecutive zero-energy domain walls is quantized to integer values, leading to a devil's staircase of topological origin. By contrast to the devil's staircase of the ANNNI and related models, the wave-vector is not fixed to commensurate values inside each phase.

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Afonso Rufino, Samuel Nyckees, Jeanne Colbois, Frédéric Mila. 2025-05-09. Topological Devil's staircase in a constrained kagome Ising antiferromagnet. https://doi.org/10.1103/dgyr-5y75

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