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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
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Atomic-level polarization reversal in sliding ferroelectric semiconductors
Fengrui Sui1, Haoyang Li1, Ruijuan Qi2,3
1Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai, 200062, China.
Nature Communications
|May 7, 2024
Summary
This study tracks atomic-level interlayer sliding in yttrium-doped γ-InSe, revealing polarization reversal. Electron beam illumination drives sliding, suggesting low switching barriers for novel electronic devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Slidetronics in van der Waals (vdW) materials and moiré superlattices show promise.
- Tracking atomic-level interlayer sliding and polarization reversal in situ remains a challenge.
Purpose of the Study:
- To in-situ trace atomic-level interlayer sliding and polarization reversal in vdW-layered yttrium-doped γ-InSe.
- To investigate the mechanism and switching barriers of electron-beam-induced sliding.
Main Methods:
- In-situ transmission electron microscopy to observe atomic-level dynamics.
- Real-time tracking of interlayer sliding and polarization changes.
Main Results:
- Direct observation of 1/3-unit cell interlayer sliding along the armchair direction in yttrium-doped γ-InSe.
- Sliding corresponds to vertical polarization reversal, driven by low-energy electron beam illumination.
- A novel sliding mechanism involving simultaneous bilayer unit movement was proposed.
Conclusions:
- Atomic-scale interlayer sliding is a viable pathway for polarization reversal in ferroelectric materials.
- Low switching barriers suggest potential for low-power electronic applications.
- Provides foundational insights for developing sliding ferroelectrics for non-volatile memory and transistors.
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