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Updated: Jul 15, 2026
07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Giant sharp and persistent converse magnetoelectric effects in multiferroic epitaxial heterostructures
W Eerenstein1, M Wiora, J L Prieto
1University of Cambridge, Department of Materials Science, Pembroke Street, Cambridge CB2 3QZ, UK.
Nature Materials
|April 10, 2007
Summary
Researchers achieved significant electric-field-induced magnetic changes in a single interface of lanthanum strontium manganite films on barium titanate substrates. This breakthrough offers potential for advanced magnetic sensors and electric-write magnetic-read memory devices.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Magnetoelectric coupling enables novel applications by linking magnetic and electrical properties.
- Existing research often focuses on magnetic-field-induced electrical changes, which are less suitable for data storage.
- Electric-field control of magnetism is crucial for developing advanced memory and sensor technologies.
Purpose of the Study:
- To demonstrate and characterize electrically induced magnetic changes at a single epitaxial interface.
- To explore the potential of such coupling for data-storage applications.
- To investigate the role of strain coupling in ferroelectric/ferromagnetic heterostructures.
Main Methods:
- Epitaxial growth of ferromagnetic La(0.67)Sr(0.33)MnO(3) films on ferroelectric BaTiO(3) substrates.
- Characterization of magnetic changes induced by electric fields using specialized measurements.
- X-ray diffraction analysis to confirm strain coupling mechanisms.
Main Results:
- Demonstration of giant, sharp, and persistent electrically induced magnetic changes (up to 2.3 x 10(-7) s m(-1)).
- Confirmation of strain coupling mediated by ferroelastic domains in BaTiO(3) via X-ray diffraction.
- Observed effects are valid across a wide temperature range, including room temperature.
Conclusions:
- Electrically induced magnetic changes at epitaxial interfaces are achievable and significant.
- This phenomenon holds promise for developing electric-write magnetic-read memory devices.
- Further research into single epitaxial interfaces is warranted for technological advancements.
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