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Updated: Sep 7, 2025
07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
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Dielectric magnetochiral anisotropy.
Geert L J A Rikken1, Narcis Avarvari2
1Laboratoire National des Champs Magnétiques Intenses UPR3228 CNRS/EMFL/INSA/UGA/UPS, Toulouse & Grenoble, France. geert.rikken@lncmi.cnrs.fr.
Nature Communications
|June 22, 2022
Summary
Magnetochiral anisotropy, a phenomenon combining magnetism and chirality, was observed in the displacement current of chiral dielectrics. This discovery extends the study of magnetochiral anisotropy to electrical properties across condensed matter.
Area of Science:
- Condensed matter physics
- Materials science
- Magnetism and chirality research
Background:
- The interplay of chirality and magnetism yields phenomena like magnetochiral anisotropy and chirality-induced spin-selectivity.
- These phenomena are observed in diverse systems including topological materials and multiferroics.
Purpose of the Study:
- To investigate the manifestation of magnetochiral anisotropy in the displacement current of chiral dielectrics under a magnetic field.
- To experimentally confirm the predicted dielectric magnetochiral anisotropy.
Main Methods:
- Symmetry arguments to predict the effect.
- Experimental measurements near ferroelectric phase transitions in triglycine sulfate and Rochelle salt.
Main Results:
- Experimental confirmation of strong dielectric magnetochiral anisotropy in chiral ferroelectrics.
- Observation of the effect near ferroelectric phase transitions.
Conclusions:
- Magnetochiral anisotropy is shown to affect the electrical properties of chiral dielectrics.
- This discovery broadens the scope of magnetochiral anisotropy to include dielectric properties in all condensed matter, from insulators to superconductors.
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