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Updated: May 30, 2026
07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Magnetic control of large room-temperature polarization
Ashok Kumar1, G L Sharma, R S Katiyar
1Department of Physics and Institute for Functional Nanomaterials, University of Puerto Rico, San Juan, PR 00931-3343, USA.
Summary
Researchers achieved room-temperature magnetic switching of electric polarization, a long-sought goal in magnetoelectricity. This breakthrough utilizes a novel coupling mechanism in a single-phase multiferroic material, enabling new device functionalities.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- The 'Holy Grail' of magnetoelectricity is room-temperature magnetic switching of electric polarization.
- Existing multiferroic materials often lack efficient switching at ambient temperatures.
- Developing single-phase multiferroics with robust magnetoelectric coupling is a key challenge.
Purpose of the Study:
- To report the achievement of room-temperature magnetic switching of large electric polarizations.
- To introduce a novel physical process for coupling magnetic and ferroelectric nanoregions.
- To demonstrate a new single-phase multiferroic material exhibiting this effect.
Main Methods:
- Fabrication of solid-state solutions of Pb(Fe(2/3)W(1/3))O(3) (PFW) and Pb(Zr(0.53)Ti(0.47))O(3) (PZT).
- Investigation of bi-relaxor properties, including ferroelectric and magnetic relaxor phenomena.
- Characterization of magnetic switching behavior and magnetoelectric coupling effects.
Main Results:
- A new room-temperature, single-phase multiferroic magnetoelectric, (PbFe(0.67)W(0.33)O(3))(0.2)(PbZr(0.53)Ti(0.47)O(3))(0.8) ('0.2PFW/0.8PZT'), was synthesized.
- Demonstrated magnetic switching of polarization from P(r) to zero with applied magnetic fields < 1 Tesla.
- Observed a significant increase in polarization relaxation time (500x) coupled with spin relaxations under magnetic field.
- The critical magnetic field (H(f)) for freezing was determined to be 0.92 ± 0.07 T, fitting the spherical random bond random field model.
Conclusions:
- The study presents a novel pathway to achieve the 'Holy Grail' of magnetoelectricity: room-temperature magnetic switching of electric polarization.
- The developed material exhibits superior or comparable properties to existing materials like BiFeO(3) in terms of polarization, loss, and resistivity.
- The unique magnetoelectric effect enables potential applications in three-state logic devices and magnetic field-sensitive condensers.
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