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Updated: May 11, 2026
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Quantitative Atomic-Site Analysis of Functional Dopants/Point Defects in Crystalline Materials by Electron-Channeling-Enhanced Microanalysis
Published on: May 10, 2021
Competing exchanges and spin-phonon coupling in Eu(1-x)R(x)MnO3 (R=Y, Lu)
D A Mota1, Y Romaguera Barcelay, P B Tavares
1IFIMUP and IN-Institute of Nanoscience and Nanotechnology, Departamento de Física e Astronomia da Faculdade de Ciências, Universidade do Porto, Porto, Portugal.
Summary
The tolerance factor reliably represents doping-induced lattice deformation in Y- and Lu-doped EuMnO3, explaining phase diagrams. Low-temperature spin-phonon coupling uniquely influences Lu-doped EuMnO3 phases.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Solid State Chemistry
Background:
- EuMnO3 exhibits complex phase diagrams influenced by doping.
- Understanding doping effects is crucial for tuning material properties.
- Manganite perovskites display competitive magnetic exchanges.
Purpose of the Study:
- Investigate phase diagrams and physical properties of Y- and Lu-doped EuMnO3.
- Evaluate the role of the tolerance factor in explaining doping-induced phase boundary variations.
- Elucidate the mechanism behind unique phase behaviors in Lu-doped EuMnO3.
Main Methods:
- Synthesis and characterization of Y- and Lu-doped EuMnO3.
- Analysis of (x,T) phase diagrams.
- Application of tolerance factor scaling for phase boundary normalization.
- Investigation of low-temperature spin-phonon coupling.
Main Results:
- Tolerance factor successfully reconciles phase boundary differences between Y- and Lu-doped EuMnO3.
- Normalization using the tolerance factor supports the role of magnetic exchanges in phase diagrams.
- A vertical phase boundary in Lu-doped EuMnO3 at ~10% Lu was observed.
- Spin-phonon coupling was identified as a key factor stabilizing specific phases in Lu-doped EuMnO3.
Conclusions:
- The tolerance factor is a robust descriptor of lattice deformation in doped EuMnO3.
- While magnetic exchanges are critical, spin-phonon coupling introduces unique phase behaviors, particularly in Lu-doped EuMnO3.
- Low-temperature spin-phonon coupling explains the stabilization of the AFM-4 phase in Lu-doped EuMnO3.
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