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Microscopic Evidence for a Zhang-Rice Triplet State in the van der Waals Antiferromagnet, ${NiPS}_{3}$

Beom Hyun Kim ^1,2,*, Youjin Lee ^1,2,*, Junik Hwang³, Junghyun Kim ^1,2, Je-Geun Park^1,2,4,†, and Seung-Ho Baek ^3,‡

¹Center for Quantum Materials, Seoul National University, Seoul 08826, Republic of Korea
²Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
³Department of Physics, Changwon National University, Changwon 51139, Republic of Korea
⁴Institute of Applied Physics, Seoul National University, Seoul 08826, Republic of Korea

^*These authors contributed equally to this work.
^†Contact author: jgpark10@snu.ac.kr
^‡Contact author: sbaek.fu@gmail.com

Phys. Rev. Lett. 137, 036505 – Published 16 July, 2026

DOI: https://doi.org/10.1103/hhtt-ffgg

Abstract

Quantum-entangled states underpin many emergent phenomena in quantum materials, yet their direct experimental identification remains a challenge. ${NiPS}_{3}$ , a van der Waals antiferromagnet exhibiting a resolution-limited magnetic exciton in its ordered phase, has been proposed to host a many-body entangled Zhang-Rice triplet state. Here, using ${}^{33}S$ nuclear magnetic resonance (NMR) on ${}^{33}S$ -enriched ${NiPS}_{3}$ single crystals, we provide microscopic evidence for this charge-transfer state. The ${}^{33}S$ and ${}^{31}P$ Knight shifts as a function of temperature reveal a unified spin-triplet configuration arising from strong hybridization between a self-doped hole in the S $3 p$ orbitals and a hole in Ni $3 d$ orbitals. Furthermore, the ${}^{33}S$ nuclear spin-lattice relaxation rate exhibits a power-law divergence as it approaches the Néel temperature $T_{N} = 155 K$ , indicating critical slowing down of collective charge fluctuations consistent with spin-nematic correlations. These results reveal a spin-charge-intertwined ground state and establish the microscopic foundation for the exceptional coherence of the magnetic exciton in ${NiPS}_{3}$ .

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Microscopic Evidence for a Zhang-Rice Triplet State in the van der Waals Antiferromagnet, ${NiPS}_{3}$

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Microscopic Evidence for a Zhang-Rice Triplet State in the van der Waals Antiferromagnet, NiPS3

Abstract

Physics Subject Headings (PhySH)

Article Text

Supplemental Material

References (37)

Microscopic Evidence for a Zhang-Rice Triplet State in the van der Waals Antiferromagnet, ${NiPS}_{3}$