Vanishing ordered moment in the frustrated triangular lattice antiferromagnet CuNdO2
Source abstract
Abstract
We investigate the magnetic ground state of CuNdO2, which is a delafossite with a triangular lattice of magnetic Nd3+ ions that are well separated by non-magnetic Cu spacer layers. From inelastic neutron scattering measurements of the crystal electric field, we determine the strong Ising character of the pseudo-spin 1/2 Nd3+ moments. Magnetic susceptibility and heat capacity measurements reveal the onset of long-range antiferromagnetic order at TN = 0.78 K. While the magnetic transition is definitively observed with muon spin relaxation, accompanied by the formation of a weakly dispersing spin wave excitation, no dipole-ordered moment is detected with neutron diffraction. We show that the apparent absence of a dipolar ordered moment is a consequence of the dominant Ising character of the antiferromagnetically coupled Nd3+ moments, which experience extreme frustration on the triangular lattice. Consequently, the frustration in CuNdO2 is relieved through in-plane ordering of the substantially smaller perpendicular component of the Nd3+ moments into a 120° structure, with a nearly vanishing ordered moment.
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Research context
OpenAlex topics: Copper-based nanomaterials and applications · Physics of Superconductivity and Magnetism · Quasicrystal Structures and Properties
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (47)
Show source-provided references
1. Greedan, J. E. Geometrically frustrated magnetic materials. J. Mater. Chem. 11, 37–53 (2001).10.1039/b003682j ↗
2. Balents, L. Spin liquids in frustrated magnets. Nature 464, 199–208 (2010).10.1038/nature08917 ↗
3. Broholm, C. et al. Quantum spin liquids. Science 367, eaay0668 (2020).10.1126/science.aay0668 ↗
4. Huse, D. A. & Elser, V. Simple variational wave functions for two-dimensional Heisenberg spin-1/2 antiferromagnets. Phys. Rev. Lett. 60, 2531 (1988).10.1103/PhysRevLett.60.2531 ↗
5. Jolicoeur, T. & Le Guillou, J. C. Spin-wave results for the triangular Heisenberg antiferromagnet. Phys. Rev. B 40, 2727 (1989).10.1103/PhysRevB.40.2727 ↗
6. Bernu, B., Lhuillier, C. & Pierre, L. Signature of Néel order in exact spectra of quantum antiferromagnets on finite lattices. Phys. Rev. Lett. 69, 2590 (1992).10.1103/PhysRevLett.69.2590 ↗
7. Elstner, N., Singh, R. & Young, A. Finite temperature properties of the spin-1/2 Heisenberg antiferromagnet on the triangular lattice. Phys. Rev. Lett. 71, 1629 (1993).10.1103/PhysRevLett.71.1629 ↗
8. White, S. R. & Chernyshev, A. Neél order in square and triangular lattice Heisenberg models. Phys. Rev. Lett. 99, 127004 (2007).10.1103/PhysRevLett.99.127004 ↗
9. Misguich, G., Lhuillier, C., Bernu, B. & Waldtmann, C. Spin-liquid phase of the multiple-spin exchange Hamiltonian on the triangular lattice. Phys. Rev. B 60, 1064 (1999).10.1103/PhysRevB.60.1064 ↗
10. Zhu, Z. & White, S. R. Spin liquid phase of the S = 1/2J1 − J2 Heisenberg model on the triangular lattice. Phys. Rev. B 92, 041105 (2015).10.1103/PhysRevB.92.041105 ↗
11. Hu, W.-J., Gong, S.-S., Zhu, W. & Sheng, D. Competing spin-liquid states in the spin-1/2 Heisenberg model on the triangular lattice. Phys. Rev. B 92, 140403 (2015).10.1103/PhysRevB.92.140403 ↗
12. Clarke, S., Fowkes, A., Harrison, A., Ibberson, R. & Rosseinsky, M. Synthesis, structure, and magnetic properties of NaTiO2. Chem. Mater. 10, 372–384 (1998).10.1021/cm970538c ↗
13. Shimizu, Y., Miyagawa, K., Kanoda, K., Maesato, M. & Saito, G. Spin liquid state in an organic Mott insulator with a triangular lattice. Phys. Rev. Lett. 91, 107001 (2003).10.1103/PhysRevLett.91.107001 ↗
14. Ye, F. et al. Spontaneous spin-lattice coupling in the geometrically frustrated triangular lattice antiferromagnet CuFeO2. Phys. Rev. B 73, 220404 (2006).10.1103/PhysRevB.73.220404 ↗
15. McQueen, T. et al. Successive orbital ordering transitions in NaVO2. Phys. Rev. Lett. 101, 166402 (2008).10.1103/PhysRevLett.101.166402 ↗
16. Li, Y.-D., Wang, X. & Chen, G. Anisotropic spin model of strong spin-orbit-coupled triangular antiferromagnets. Phys. Rev. B 94, 035107 (2016).10.1103/PhysRevB.94.035107 ↗
17. Li, Y.-D., Wang, X. & Chen, G. Hidden multipolar orders of dipole-octupole doublets on a triangular lattice. Phys. Rev. B 94, 201114 (2016).10.1103/PhysRevB.94.201114 ↗
18. Luo, Q., Hu, S., Xi, B., Zhao, J. & Wang, X. Ground-state phase diagram of an anisotropic spin-1/2 model on the triangular lattice. Phys. Rev. B 95, 165110 (2017).10.1103/PhysRevB.95.165110 ↗
19. Iaconis, J., Liu, C.-X., Halasz, G. & Balents, L. Spin liquid versus spin orbit coupling on the triangular lattice. SciPost Phys. 4, 003 (2018).10.21468/SciPostPhys.4.1.003 ↗
20. Zhu, Z., Maksimov, P., White, S. R. & Chernyshev, A. Topography of spin liquids on a triangular lattice. Phys. Rev. Lett. 120, 207203 (2018).10.1103/PhysRevLett.120.207203 ↗
21. Liu, C., Li, Y.-D. & Chen, G. Selective measurements of intertwined multipolar orders: Non-Kramers doublets on a triangular lattice. Phys. Rev. B 98, 045119 (2018).10.1103/PhysRevB.98.045119 ↗
22. Bordelon, M. M. et al. Field-tunable quantum disordered ground state in the triangular-lattice antiferromagnet NaYbO2. Nat. Phys. 15, 1058–1064 (2019).10.1038/s41567-019-0594-5 ↗
23. Li, Y. et al. Rare-earth triangular lattice spin liquid: a single-crystal study of YbMgGaO4. Phys. Rev. Lett. 115, 167203 (2015).10.1103/PhysRevLett.115.167203 ↗
24. Paddison, J. A. et al. Continuous excitations of the triangular-lattice quantum spin liquid YbMgGaO4. Nat. Phys. 13, 117–122 (2017).10.1038/nphys3971 ↗
25. Somesh, K. et al. Absence of magnetic order and emergence of unconventional fluctuations in the Jeff = 1/2 triangular-lattice antiferromagnet YbBO3. Phys. Rev. B 107, 064421 (2023).10.1103/PhysRevB.107.064421 ↗
26. Bag, R. et al. Evidence of Dirac quantum spin liquid in YbZn2GaO5. Phys. Rev. Lett. 133, 266703 (2024).10.1103/PhysRevLett.133.266703 ↗
27. Miyasaka, N., Doi, Y. & Hinatsu, Y. Synthesis and magnetic properties of ALnO2 (A = Cu or Ag; Ln = rare earths) with the delafossite structure. J. Solid State Chem. 182, 2104–2110 (2009).10.1016/j.jssc.2009.05.035 ↗
28. Mugiraneza, S. & Hallas, A. M. Tutorial: a beginner’s guide to interpreting magnetic susceptibility data with the Curie-Weiss law. Commun. Phys. 5, 95 (2022).10.1038/s42005-022-00853-y ↗
29. Gao, S. et al. Crystal electric field excitations in the quantum spin liquid candidate NaErS2. Phys. Rev. B 102, 024424 (2020).10.1103/PhysRevB.102.024424 ↗
30. Scheie, A., Garlea, V. O., Sanjeewa, L. D., Xing, J. & Sefat, A. S. Crystal-field hamiltonian and anisotropy in KErSe2 and CsErSe2. Phys. Rev. B 101, 144432 (2020).10.1103/PhysRevB.101.144432 ↗
31. Rau, J. G. & Gingras, M. J. Frustrated quantum rare-earth pyrochlores. Annu. Rev. Condens. Matter Phys. 10, 357–386 (2019).10.1146/annurev-conmatphys-022317-110520 ↗
32. Zapf, V. S. et al. Magnetization dynamics and frustration in the multiferroic double perovskite Lu2MnCoO6. Phys. Rev. B 93, 134431 (2016).10.1103/PhysRevB.93.134431 ↗
33. Ziat, D. et al. Frustrated spin-$${\frac{1}2}$$ molecular magnetism in the mixed-valence antiferromagnets Ba3MRu2O9 (M = In, Y, Lu).Phys. Rev. B. 95, 184424 (2017).10.1103/PhysRevB.95.184424 ↗
34. Mutch, H. et al. Long-and short-range magnetism in the frustrated double perovskite Ba2MnWO6. Phys. Rev. Mater. 4, 014408 (2020).10.1103/PhysRevMaterials.4.014408 ↗
35. Pourovskii, L. V. et al. Hidden orders in spin–orbit-entangled correlated insulators. Nat. Rev. Mater. 1–23 (2025).10.1038/s41578-025-00824-z ↗
36. Cava, R. J. et al. LaCuO2.5+x and YCuO2.5+x delafossites: materials with triangular Cu2+δ planes. J. Solid State Chem. 104, 437–452 (1993).10.1006/jssc.1993.1179 ↗
37. Isawa, K. et al. Synthesis of delafossite-derived phases, RCuO2+δ with R = Y, La, Pr, Nd, Sm, and Eu, and observation of spin-gap-like behavior. Phys. Rev. B 56, 3457 (1997).10.1103/PhysRevB.56.3457 ↗
38. Rodríguez-Carvajal, J. Recent advances in magnetic structure determination by neutron powder diffraction. Phys. B Condens. Matter 192, 55–69 (1993).10.1016/0921-4526(93)90108-I ↗
39. Wills, A. A new protocol for the determination of magnetic structures using simulated annealing and representational analysis (SARAh). Phys. B: Condens. Matter 276, 680–681 (2000).10.1016/S0921-4526(99)01722-6 ↗
40. Granroth, G. et al. SEQUOIA: a newly operating chopper spectrometer at the SNS. In Journal of Physics: Conference Series, vol. 251, 012058 (IOP Publishing, 2010).10.1088/1742-6596/251/1/012058 ↗
41. Scheie, A. PyCrystalField: software for calculation, analysis and fitting of crystal electric field Hamiltonians. J. Appl. Crystallogr. 54, 356–362 (2021).10.1107/S160057672001554X ↗
42. Gaudet, J., Hallas, A. M., Kolesnikov, A. I. & Gaulin, B. D. Effect of chemical pressure on the crystal electric field states of erbium pyrochlore magnets. Phys. Rev. B 97, 024415 (2018).10.1103/PhysRevB.97.024415 ↗
43. Reig-i Plessis, D. et al. Neutron scattering measurement of crystalline-electric fields in magnesium rare-earth selenide spinels. Phys. Rev. Mater. 3, 114408 (2019).10.1103/PhysRevMaterials.3.114408 ↗
44. Jensen, J. & Mackintosh, A. R. Rare earth magnetism: structures and excitations (Oxford University Press, 1991).10.1093/oso/9780198520276.001.0001 ↗
45. Mesota, J., Janssen, S., Holitzner, L. & Hempelmann, R. FOCUS: Project of a space and time focussing time-of-flight spectrometer for cold neutrons at the Spallation Source SINQ of the Paul Scherrer Institute. J. Neutron Res. 3, 293–310 (1996).10.1080/10238169608200202 ↗
46. Momoi, T. & Suzuki, M. Ground-State Properties and Phase Diagram of the Quantum XXZ antiferromagnet on a triangular lattice. J. Phys. Soc. Jpn. 61, 3732–3744 (1992).10.1143/JPSJ.61.3732 ↗
47. Dahlbom, D. et al. Sunny.jl: a Julia package for spin dynamics. arXiv:2501.13095 https://arxiv.org/abs/2501.13095 (2025).