Effect of the Non-Magnetic Ion Doping on the Magnetic Behavior of MgCr2O4
Geometrically frustrated magnets exhibit exotic excitations due to competing interactions between spins. The spinel compound MgCr2O4, a three-dimensional Heisenberg antiferromagnet, hosts both spin-wave and spin-resonance modes, but the origin of its resonant excitations remains debated. Suppressing magnetic order via non-magnetic doping can help isolate these modes in neutron scattering studies. We synthesized Ga3+ and Cd2+-doped MgCr2O4 via solid-state reaction and analyzed their structure and magnetism. Ga3+ doping (0–20%) causes anomalous lattice shrinkage due to site disorder from Ga3+ occupying both Mg2+ and Cr3+ sites. Magnetically, Ga3+ doping drives the system from the antiferromagnetic order to a spin-glass state, fully suppressing magnetic ordering at 20% doping. In contrast, Cd2+ replaces only Mg2+, expanding the lattice and meantime inducing strong spin-glass behavior. At 10% Cd2+, long-range antiferromagnetic order is entirely suppressed. Thus, 10% Cd-doped MgCr2O4 offers an ideal platform to study the resonant magnetic excitations without any spin-wave interference.
Authors
- Yanchun Zhao (ORCID: https://orcid.org/0000-0002-2726-3965)
- Xinzhi Liu (ORCID: https://orcid.org/0000-0003-3572-2807)
- Han Ge (ORCID: https://orcid.org/0000-0002-7981-0019)
- Zheng He
- Donger Cheng
- Lunhua He (ORCID: https://orcid.org/0000-0002-0531-2148)
- Erxi Feng (ORCID: https://orcid.org/0000-0002-3703-1164)
- Wenjing Zhang (ORCID: https://orcid.org/0000-0001-6263-5384)
- Liusuo Wu (ORCID: https://orcid.org/0000-0003-0103-5267)
- Fuwei Zhou (ORCID: https://orcid.org/0009-0003-8709-0773)
- Zhengdong Fu
- Pengfei Zhou (ORCID: https://orcid.org/0000-0002-8655-2927)
- Xiao Wang (ORCID: https://orcid.org/0000-0002-6539-9732)
- Wanju Luo
Institutions
- Wenzhou University (CN)
- Sun Yat-sen University (CN)
- Chinese Academy of Sciences (CN)
- Lanzhou University of Technology (CN)
- Southern University of Science and Technology (CN)
- China Spallation Neutron Source (CN)
- Songshan Lake Materials Laboratory (CN)
- Institute of High Energy Physics (CN)
- Institute of Physics (CN)
Publication Details
- Journal
- Magnetism
- Published
- 2025-08-25
- DOI
- https://doi.org/10.3390/magnetism5030019
- Primary Topic
- Advanced Condensed Matter Physics
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Natural Science Foundation of China
- China Postdoctoral Science Foundation