Abstract
Quantum fluctuations endow spin systems with surprisingly enriched magnetic phase diagrams. In frustrated magnets, strong quantum fluctuations boosted by either geometrical incompatibility or competitive exchange interactions stabilize cascades of unusual phases of matter. Here we reveal the presence of multiple quantum phases in the honeycomb antiferromagnet Na3Ni2BiO6, both inside and beyond its field-induced one-third magnetization plateau. Comprehensive measurements of thermodynamic quantities demonstrate that the one-third plateau comprises at least three distinct spin states with nearly-degenerate net magnetization, separated by first-order transitions that likely involve sequential spin reconfiguration. Upon further increasing the magnetic field, the system evolves across a myriad of peculiar phases before reaching full polarization; these intermediate phases possess copious low-energy excitations, manifested by anomalous upturns of specific heat at ultralow temperatures — probably hinting at the development of “hidden” ordered ground states. The complex magnetic phase diagram of Na3Ni2BiO6 underlines the preponderant impact of quantum fluctuations on a honeycomb spin lattice with strong exchange frustration.
Acknowledgements
We thank Zhentao Wang, Yisheng Chai, Shunli Yu and Shang Gao for insightful discussions. We gratefully acknowledge Jiyin Zhao, Xuguang Liu and Jun Zhou for assistance in the sample characterization performed at the Instruments Center for Physical Science, University of Science and Technology of China, and Yuyan Han for the support of magnetization measurements performed at the High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei.
Funding
This work was financially supported by the National Key Projects for Research and Development of China with Grants Nos. 2022YFA1602600 (Z.X. and X.C.) and 2021YFA1400400 (J.W. and J.-X.L.), the National Natural Science Foundation of China with Grants Nos. 12274390 (Z.X.), 12488201 (Z.X.), 12225407 (J.W.), 12434005 (J.W.), 12574158 (Z.-Y.D.) and 12204449 (Y.Y.), the Quantum Science and Technology-National Science and Technology Major Project with Grant No. 2021ZD0302802 (Z.X. and X.C.), the Natural Science Foundation of Jiangsu Province with Grant No. BK20241250 (Y.S.) and the Basic Research Program of the Chinese Academy of Sciences Based on Major Scientific Infrastructures (Grant No. JZHKYPT-2021-08 to Z.X. and X.C.).
Author information
Authors and Affiliations
Corresponding authors
Ethics declarations
Competing interests
The authors declare no competing interests.
Additional information
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary information
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
About this article
Cite this article
Tang, K., Dong, ZY., Shangguan, Y. et al. Cascade of magnetic-field-induced quantum spin states in a spin-1 honeycomb magnet. Nat Commun (2026). https://doi.org/10.1038/s41467-026-73419-z
Received:
Accepted:
Published:
DOI: https://doi.org/10.1038/s41467-026-73419-z
