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Updated: Oct 16, 2025
07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
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In Situ Electric-Field Control of THz Nonreciprocal Directional Dichroism in the Multiferroic Ba_{2}CoGe_{2}O_{7}
J Vít1,2,3, J Viirok4, L Peedu4
1Department of Physics, Budapest University of Technology and Economics, 1111 Budapest, Hungary.
Physical Review Letters
|October 22, 2021
Summary
Researchers demonstrate electric control of nonreciprocal light absorption in magnets. By manipulating antiferromagnetic domains, they achieved an optical-diode effect, paving the way for new electronic devices.
Area of Science:
- Condensed Matter Physics
- Magnetism
- Optical Properties of Materials
Background:
- Nonreciprocal directional dichroism (optical-diode effect) is a property of noncentrosymmetric magnets.
- In situ electric control of this effect is challenging due to specific symmetry and excitation requirements.
Purpose of the Study:
- To demonstrate the isothermal electric switching of magnetoelectric domains.
- To achieve electric control over nonreciprocal light absorption in magnets.
Main Methods:
- Utilized Terahertz (THz) spectroscopy.
- Employed multiboson spin-wave analysis.
- Investigated Ba_{2}CoGe_{2}O_{7} single crystals.
Main Results:
- Achieved isothermal electric switching between domains with opposite magnetoelectric susceptibilities.
- Demonstrated that unbalancing antiferromagnetic domain populations generates nonreciprocal light absorption.
- Showcased the optical-diode effect in response to electric control.
Conclusions:
- The study successfully demonstrates electric control of nonreciprocal light absorption.
- This work highlights the potential of noncentrosymmetric magnets for optoelectronic applications.
- The findings pave the way for novel magnetoelectric devices.
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