Abstract
The question of structural disorder and its effects on magnetism is relevant to a number of spin liquid candidate materials. Although commonly thought of as a route to spin glass behaviour, here we describe a system in which the structural disorder results in long-range antiferromagnetic order due to local symmetry breaking. Nd2ScNbO7 is shown to have a dispersionless gapped excitation observed in other neodymium pyrochlores below TN = 0.37 K through polarized and inelastic neutron scattering. However the dispersing spin waves are not observed. This excited mode is shown to occur in only 14(2)% of the neodymium ions through spectroscopy and is consistent with total scattering measurements as well as the magnitude of the dynamic moment 0.26(2) μB. The remaining magnetic species order completely into the all-in all-out Ising antiferromagnetic structure. This can be seen as a result of local symmetry breaking due disordered Sc+3 and Nb+5 ions about the A-site. From this work, it has been established that B-site disorder restores the dipole-like behaviour of the Nd+3 ions compared to the Nd2B2O7 parent series.
| Original language | English |
|---|---|
| Article number | 245802 |
| Journal | Journal of Physics Condensed Matter |
| Volume | 33 |
| Issue number | 24 |
| DOIs | |
| State | Published - Jun 2021 |
Funding
The authorswould like to thank JeffreyGRau for his important insights, and the experimental aid provided by Graham King. This research was funded in part by the National Science and Engineering Research Council of Canada (NSERC), and the Canadian Foundation for Innovation (CFI). C R Wiebe would like to thank the Canadian Institution For Advanced Research (CIFAR), the Canada Research Chair programme (Tier II), and the Leverhulme Trust. C Mauws would like to thank NSERC for the AlexanderGraham Bell Scholarship. QH and HZ thank the support from NSF-DMR-1350002. The work performed in NHMFL was supported by NSF-DMR-1157490 and the State of Florida. A portion of this research used resources at the SNS, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. An additional portion of this work used resources at the NCNR inGaithersburg, USA(operated by the National Institute of Standards and Technology), and at the Heinz Maier-Leibnitz Zentrum in Garching, Germany. Part or all of the research described in this paper was performed at the Canadian Light Source, a national research facility of the University of Saskatchewan, which is supported by the Canada Foundation for Innovation (CFI), the Natural Sciences and Engineering Research Council (NSERC), the National Research Council (NRC), the Canadian Institutes of Health Research (CIHR), the Government of Saskatchewan, and the University of Saskatchewan.
| Funders | Funder number |
|---|---|
| Government of Saskatchewan | |
| Heinz Maier-Leibnitz Zentrum in Garching | |
| NSF-DMR-1350002 | NSF-DMR-1157490 |
| State of Florida | |
| National Institute of Standards and Technology | |
| Office of Science | |
| Oak Ridge National Laboratory | |
| NIST Center for Neutron Research | |
| University of Saskatchewan | |
| National Research Council | |
| Canadian Institutes of Health Research | |
| Natural Sciences and Engineering Research Council of Canada | |
| Canada Foundation for Innovation | |
| Leverhulme Trust | |
| Canada Research Chairs |
Keywords
- Frustrated magnetism
- Neutron scattering
- Spin ice