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arXiv · 2509.09060

Realization of a Spin-1/2 Hexagonal-Plaquette Chain with Ising-Like Anisotropy

Hironori Yamaguchi·Shunsuke C. Furuya·Yu Tominaga·Koji Araki·Masayuki Hagiwara
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Abstract

We present the realization of a spin-1/2 hexagonal-plaquette chain with Ising anisotropy, an unexplored quantum spin model that serves as a platform for investigating anisotropic quantum magnetism. Specific heat at zero field reveals a sharp peak at $T_{\rm{N}}$ = 1.0 K, indicating a phase transition to a N$\acute{\rm{e}}$el order stabilized by interchain couplings. A perturbative analysis maps the system onto an effective spin-1/2 Ising-like chain, supporting the presence of an anisotropy-induced excitation gap. Furthermore, the interchain interactions may induce discrete excitations in the spinon continuum, reminiscent of Zeeman ladder physics observed in related 1D Ising-like systems. These results establish a well-defined model system for correlated spin phenomena in anisotropic magnets and highlight a route for engineering Ising-like quantum states in molecular-based frameworks.

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Hironori Yamaguchi, Shunsuke C. Furuya, Yu Tominaga, Koji Araki, Masayuki Hagiwara. 2025-09-10. Realization of a Spin-1/2 Hexagonal-Plaquette Chain with Ising-Like Anisotropy. https://doi.org/10.1103/98jq-y7gh

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