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Updated: May 31, 2026
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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Observation of phonons in multiferroic BiFeO(3) single crystals by Raman scattering.
H Fukumura1, S Matsui, H Harima
1Department of Electronics and Information Science, Kyoto Institute of Technology, Kyoto 606-8585, Japan.
Summary
Researchers studied bismuth ferrite (BiFeO3) single crystals using Raman scattering across a wide temperature range. They observed all predicted phonon modes and significant spectral changes linked to magnetic and structural transitions.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spectroscopy
Background:
- Bismuth ferrite (BiFeO3) is a multiferroic material with potential applications.
- Understanding its phonon behavior is crucial for its technological use.
- Previous studies have explored its properties, but detailed temperature-dependent phonon spectra are less understood.
Purpose of the Study:
- To grow high-quality BiFeO3 bulk single crystals.
- To characterize the temperature-dependent phonon spectra using Raman scattering.
- To investigate the relationship between phonon behavior, magnetic ordering, and structural phase transitions.
Main Methods:
- Flux method for growing BiFeO3 bulk single crystals.
- Raman scattering spectroscopy from 4 K to 1100 K.
- Polarized Raman measurements for mode assignment.
Main Results:
- Successfully grew BiFeO3 bulk single crystals.
- Observed all 13 predicted Raman-active phonon modes (4A1 + 9E) at low temperatures.
- Identified drastic spectral changes in Raman spectra between 600-700 K and 1000-1100 K.
Conclusions:
- The observed phonon modes were assigned based on group theory and polarized measurements.
- Spectral changes at 600-700 K are attributed to phonon coupling with magnetic ordering.
- Spectral changes at 1000-1100 K are linked to structural phase transitions.
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