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Two-magnon scattering in the 5d all-in-all-out pyrochlore magnet Cd2Os2O7
Thi Minh Hien Nguyen1,2, Luke J Sandilands1,2,3, C H Sohn1,2
1Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, 151-742, Republic of Korea.
Nature Communications
|August 17, 2017
Summary
Raman spectroscopy reveals spin dynamics in 5d pyrochlores like Cd2Os2O7, confirming magnetic interactions and complex coupling. This method offers a powerful new way to study these exotic magnetic materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- 5d pyrochlore oxides with all-in-all-out magnetic order are key for exploring strongly correlated, topological phases.
- Understanding all-in-all-out magnetism is challenging due to difficulties in accessing magnetic excitations with conventional methods.
Purpose of the Study:
- To investigate spin dynamics in the all-in-all-out magnetic state of the 5d pyrochlore Cd2Os2O7 using Raman spectroscopy.
- To establish Raman scattering as an effective technique for studying spin dynamics in 5d pyrochlore magnets.
Main Methods:
- Raman spectroscopy was employed to study spin dynamics in Cd2Os2O7.
- Two-magnon scattering data were compared with spin-wave theory to analyze magnetic excitations.
Main Results:
- Large single ion anisotropy was confirmed in Cd2Os2O7.
- Dzyaloshinskii-Moriya and exchange interactions were shown to significantly influence spin-wave dispersions.
- Complex spin-charge-lattice coupling was observed.
- The metal-insulator transition in Cd2Os2O7 was identified as Lifshitz-type.
Conclusions:
- Raman scattering is a simple and powerful technique for probing spin dynamics in 5d pyrochlore magnets.
- The study provides insights into the magnetic interactions and coupling phenomena in Cd2Os2O7.
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