1. Direct confirmation of long-range magnetic order and evidence for multipoles in Ce$_{2}$O$_{3}$
- Author
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Cote, Alexandra, Slimak, J. Eddie, Sethi, Astha, Reig-i-Plessis, Dalmau, Zhang, Qiang, Zhao, Yang, Adroja, Devashibhai, Morris, Gerald, Kolodiazhnyi, Taras, Hallas, Alannah M., Lynn, Jeffrey W., Cooper, S. Lance, and MacDougall, Gregory J.
- Subjects
Condensed Matter - Strongly Correlated Electrons - Abstract
The sesquioxide, Ce$_{2}$O$_{3}$, has been a material of intense interest in recent years due to reports of an anomalous giant magnetodielectric effect and emergent mixed crystal field-phonon (vibronic) excitations below a putative antiferromagnetic transition at T$_{N}$ = 6.2 K. The claim of long-range magnetic order in this material is based on heat capacity and temperature-dependent susceptibility measurements; however, multiple neutron diffraction studies have been unable to distinguish any magnetic Bragg peaks. In this article, we present the results of a comprehensive investigation of the low-temperature phase in symmetry-broken polycrystalline Ce$_{2}$O$_{3}$ using a combination of magnetic susceptibility, heat capacity, neutron diffraction, triple-axis and time-of-flight (TOF) inelastic neutron scattering (INS), and muon spin rotation ($\mu$SR). Our measurements and subsequent analysis confirm that the transition at T$_{N}$ can be associated with the ordering of moments on the Ce$^{3+}$ site. Both a spontaneous magnetic order observed with $\mu$SR and a dispersive spin-wave spectrum observed with inelastic neutron scattering suggest a model wherein planar dipoles order antiferromagnetically. Notable inconsistencies between $\mu$SR and neutron scattering data within the dipole picture provide strong evidence for the ordering of higher-order moments., Comment: 12 pages, 8 figures
- Published
- 2023