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Updated: Sep 11, 2025
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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
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Interlayer Sliding Induced Triferroic Coupling in 2D Bilayer NbSi2N4.
Yue Yang1, Ying Zhao1, Fanhan Kong1
1Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Ministry of Education), Dalian University of Technology, Dalian 116024, China.
The Journal of Physical Chemistry Letters
|August 14, 2025
Summary
Interlayer sliding in 2D NbSi2N4 creates multiferroic coupling. This breakthrough enables novel non-volatile memory and spin-valleytronic devices by controlling magnetism, ferroelectricity, and valley polarization.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Interlayer sliding symmetry breaking is key for multiferroic coupling.
- Multifunctional devices require integrated magnetic, ferroelectric, and valley properties.
Purpose of the Study:
- Investigate multiferroic coupling in 2D NbSi2N4 using first-principles calculations.
- Explore the potential of NbSi2N4 for advanced electronic devices.
Main Methods:
- First-principles calculations.
- Magneto-optic Kerr effect (MOKE) measurements.
- Analysis of anomalous valley Hall effect (AVHE).
Main Results:
- Monolayer NbSi2N4 shows ferromagnetic ground state with tunable valley polarization.
- AB/BA-stacked bilayer exhibits antiferromagnetism, ferrovalley, and ferroelectricity.
- Interlayer sliding induces non-volatile ferroelectric bistability.
- Magnetoelectric coupling confirmed via MOKE.
- Electric/magnetic fields control valley polarization, leading to AVHE and spin currents.
Conclusions:
- NbSi2N4 is a promising platform for multiferroic applications.
- The material supports novel non-volatile memory and spin-valleytronic devices.
- Interlayer sliding is a viable mechanism for device control.
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