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Updated: Aug 7, 2025
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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
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Axion optical induction of antiferromagnetic order
Jian-Xiang Qiu1, Christian Tzschaschel1, Junyeong Ahn2
1Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA.
Nature Materials
|March 9, 2023
Summary
Researchers discovered a new way to control antiferromagnetic order using circularly polarized light in MnBi2Te4. This optical control, based on axion electrodynamics, could enable new dissipationless circuits.
Area of Science:
- Quantum Matter Physics
- Materials Science
- Spintronics
Background:
- Controlling quantum matter with light is crucial for advancements in physics, chemistry, and biology.
- Previous research focused on controlling chirality and magnetization using light.
- Antiferromagnetic materials offer potential for spintronic applications due to their fast dynamics and dissipationless nature.
Purpose of the Study:
- To investigate the helicity-dependent optical control of antiferromagnetic order in two-dimensional (2D) MnBi2Te4.
- To understand the underlying mechanism of this optical control, particularly in a material lacking chirality and net magnetization.
- To explore the potential of this phenomenon for new technological applications, such as dissipationless circuits.
Main Methods:
- Experimental investigation of MnBi2Te4 using circularly polarized light.
- Analysis of antiferromagnetic circular dichroism (AFM-CD) in reflection and transmission.
- Theoretical modeling based on optical axion electrodynamics.
Main Results:
- Demonstrated helicity-dependent optical control of fully compensated antiferromagnetic order in 2D MnBi2Te4.
- Observed antiferromagnetic circular dichroism (AFM-CD) exclusively in reflection, not transmission.
- Established that optical control and AFM-CD originate from optical axion electrodynamics.
Conclusions:
- Optical axion electrodynamics provides a mechanism for controlling antiferromagnetic order in materials with specific symmetries.
- This discovery opens possibilities for optical control of various antiferromagnetic materials, including Cr2O3 and CrI3.
- The findings pave the way for optical writing of dissipationless circuits utilizing topological edge states in MnBi2Te4.
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