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Updated: Jan 16, 2026
09:25
Fabricating van der Waals Heterostructures with Precise Rotational Alignment
Published on: July 5, 2019
10.1K
Revealing atomic-scale switching pathways in van der Waals ferroelectrics.
Xinyan Li1,2, Kenna Ashen3, Chuqiao Shi1
1Department of Materials Science and NanoEngineering, Rice University, Houston, TX, USA.
Science Advances
|October 3, 2025
Summary
Two-dimensional (2D) van der Waals ferroelectric materials exhibit unique switching pathways. Researchers uncovered simultaneous interlayer sliding and strain during switching in SnSe, crucial for designing ultrascaled ferroelectric devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Two-dimensional (2D) van der Waals (vdW) materials offer potential for ultrascaled ferroelectric (FE) devices.
- Weak vdW interactions complicate switching pathways compared to conventional ferroelectrics.
Purpose of the Study:
- To unravel the atomic-scale switching mechanisms in 2D vdW ferroelectric SnSe.
- To investigate the interplay between electrical biasing, interlayer sliding, and ferroelectric switching.
Main Methods:
- Atomic-resolution imaging under in situ electrical biasing.
- First-principles calculations.
- Strain analysis.
Main Results:
- Uncovered coexistence of consecutive 90° and direct 180° switching pathways from antiferroelectric (AFE) to FE order in SnSe.
- Observed simultaneous interlayer sliding and compressive strain during switching.
- Demonstrated lattice coherence despite multidomain structures.
Conclusions:
- Elucidated atomic-scale switching dynamics in vdW ferroelectrics.
- Provided insights into the role of interlayer sliding and strain.
- Laid the foundation for rational design of 2D ferroelectric nanodevices.
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