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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Charge order, dynamics, and magnetostructural transition in multiferroic LuFe2O4.
X S Xu1, M Angst, T V Brinzari
1Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA.
Physical Review Letters
|December 31, 2008
Summary
Charge fluctuations in LuFe2O4 precede ordering, supporting an "order by fluctuation" mechanism. A monoclinic distortion, driven by temperature and magnetic fields, is observed in this multiferroic material.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism and Multiferroics
Background:
- LuFe2O4 is a multiferroic material exhibiting complex transitions.
- Understanding the interplay of charge, structure, and magnetism is crucial for its applications.
Purpose of the Study:
- Investigate temperature and field-driven transitions in LuFe2O4.
- Elucidate the mechanism behind charge order superstructure formation.
- Characterize the low-temperature structural distortion.
Main Methods:
- Optical spectroscopy
- Mössbauer spectroscopy
- Magnetization measurements
- X-ray scattering
Main Results:
- Charge fluctuation onset observed well below the charge ordering transition.
- Evidence supporting the "order by fluctuation" mechanism for charge order superstructure.
- Bragg splitting and large magneto-optical contrast indicate a low-temperature monoclinic distortion.
- This distortion is controllable by both temperature and magnetic field.
Conclusions:
- Charge fluctuations play a key role in the development of charge order in LuFe2O4.
- A temperature and magnetic field-driven monoclinic distortion exists at low temperatures.
- These findings provide insights into the multiferroic behavior of LuFe2O4.
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