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Updated: May 18, 2026
07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
magnetic dispersion and anisotropy in multiferroic BiFeO3
M Matsuda1, R S Fishman, T Hong
1Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
Physical Review Letters
|September 26, 2012
Summary
Researchers mapped the magnetic properties of multiferroic BiFeO3, revealing magnetic anisotropies. This allowed precise measurement of the Dzyaloshinskii-Moriya interaction, crucial for magnetoelectric coupling in this material.
Area of Science:
- Condensed matter physics
- Materials science
- Magnetism
Background:
- Multiferroic materials exhibit unique magnetoelectric properties.
- BiFeO3 is a prominent multiferroic material with potential applications.
Purpose of the Study:
- To determine the full magnetic dispersion relations of multiferroic BiFeO3.
- To investigate the origins of magnetic anisotropies and their impact on material properties.
Main Methods:
- Magnetic excitation measurements.
- Analysis of magnetic dispersion relations.
- Determination of anisotropy parameters.
Main Results:
- Full magnetic dispersion relations of BiFeO3 were determined.
- Two distinct excitation gaps were observed, attributed to magnetic anisotropies.
- Accurate values for Dzyaloshinskii-Moriya interaction and single ion anisotropy were obtained.
Conclusions:
- The observed excitation gaps provide a direct route to quantify magnetic interactions in BiFeO3.
- The determined Dzyaloshinskii-Moriya interaction is significant and supports substantial magnetoelectric coupling.
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