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arXiv · 2605.29896

Field-induced multipolar character in the dipolar ground state of the honeycomb rare-earth chalcohalide NdOF

Tiantian Liu·Yanzhen Cai·Mingtai Xie·Helin Mei·Anmin Zhang·Feng Jin·Jianting Ji·Zheng Zhang·Qingming Zhang
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Abstract

Field-tunable reconstruction of crystalline electric field (CEF) doublets offers a promising avenue for inducing multipolar character, while its observation in real materials has been little explored so far. Here we establish the honeycomb rare-earth chalcohalide NdOF as such a platform. Raman spectroscopy identifies four CEF excitations at 1.7, 15.6, 19.2, and 80.9~meV, and a Zeeman--CEF analysis reproduces their nonlinear field splitting into seven branches. Magnetization and susceptibility over 0.1--9~T are well described by a CEF model for the total angular momentum $J = 9/2$ manifold, confirming the robustness of the extracted CEF scheme. These results demonstrate a field-driven continuous evolution of the ground-state doublet from dipolar to dipolar-multipolar character, with pressure providing a complementary tuning knob, establishing NdOF as a model system for exploring the controlled induction of multipolar components in rare-earth magnets.

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Tiantian Liu, Yanzhen Cai, Mingtai Xie, Helin Mei, Anmin Zhang, Feng Jin, Jianting Ji, Zheng Zhang, Qingming Zhang. 2026-05-28. Field-induced multipolar character in the dipolar ground state of the honeycomb rare-earth chalcohalide NdOF. https://doi.org/10.1103/1898-3v32

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