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arXiv · 2409.07807

Braided Ising spin-tube physics in a purported kagome magnet

J. Nagl·D. Flavián·B. Duncan·S. Hayashida·O. Zaharko·E. Ressouche·J. Ollivier·Z. Yan·S. Gvasaliya·A. Zheludev
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Abstract

The magnetic insulator Nd$_3$BWO$_9$ has been previously proposed to realize the highly frustrated breathing kagome lattice model. We report a combination of single-crystal neutron scattering studies and numerical simulations that debunk this interpretation. We show that it is the inter-plane couplings that determine the physics. To explain the exotic magnetism, we derive a simple one-dimensional Ising model composed of twisted triangular spin-tubes, i.e., triple braids of Ising spin chains with almost-orthogonal anisotropy frames and competing ferro-antiferromagnetic interactions. This model can account for the ground state, excitations, the numerous field-induced fractional magnetization plateau phases and incommensurate magnetic correlations at elevated temperatures. Nd$_3$BWO$_9$ constitutes a rare example where rich magnetic phenomena can be understood and simulated quantitatively in terms of a simple classical Hamiltonian.

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J. Nagl, D. Flavián, B. Duncan, S. Hayashida, O. Zaharko, E. Ressouche, J. Ollivier, Z. Yan, S. Gvasaliya, A. Zheludev. 2024-09-12. Braided Ising spin-tube physics in a purported kagome magnet. https://doi.org/10.1103/physrevb.111.l180406

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