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Updated: Jan 26, 2026
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Electric-field Control of Electronic States in WS2 Nanodevices by Electrolyte Gating
Published on: April 12, 2018
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Electric-Field Control of Terahertz Response via Spin-Corner-Layer Coupling in Altermagnetic Bilayers
Jianhua Wang1,2, Yilin Han3, Shifeng Qian4
1School of Material Science and Engineering, Tiangong University, Tianjin, China.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|January 25, 2026
Summary
Researchers developed a new spin-corner-layer coupling (SCLC) mechanism. This allows electric fields to control terahertz (THz) waves by manipulating electron spin and layer properties in altermagnetic materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Electric field control is crucial for semiconductors and spintronics.
- Controlling terahertz (THz) electromagnetic waves with electric fields is challenging.
Purpose of the Study:
- To propose and demonstrate a novel mechanism for electric-field control of THz waves.
- To enable simultaneous control of electron spin and layer degrees of freedom.
Main Methods:
- Theoretical proposal of spin-corner-layer coupling (SCLC) mechanism.
- Utilizing second-order topological altermagnetic bilayers.
- Experimental demonstration using bilayer NiZrI6 nanodisks.
Main Results:
- SCLC enables electric-field tuning of THz wave absorption, emission, and polarization.
- An ultralow electrostatic field can switch spin and layer polarizations of corner states.
- Modulation of transition dipole moments and oscillator strengths allows THz wave manipulation.
Conclusions:
- Established a mechanism for electric-field control of spin and THz waves via SCLC.
- Significant implications for the advancement of THz spintronics.
- Demonstrated dual switching of spin and layer polarizations in NiZrI6.
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