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Updated: May 21, 2026
04:57
Residue-Free Fabrication of van der Waals Heterostructures of Two-Dimensional Materials
Published on: July 18, 2025
Modulating Roughness and Ripple Dynamics in Hexagonal Boron Nitride via Defect Engineering
Md Rakib Hassan1, Owen R Dunton1, Francis W Starr1
1Department of Physics, Wesleyan University, Middletown, Connecticut 06459, United States.
Summary
We developed a machine learning model to study atomic defects in hexagonal boron nitride (hBN). Our findings reveal how defects influence hBN
Area of Science:
- Materials Science
- Condensed Matter Physics
- Computational Materials Science
Background:
- Two-dimensional (2D) materials like hexagonal boron nitride (hBN) possess intrinsic roughness and thermal rippling.
- The impact of atomic defects on these dynamics in hBN is not well understood.
- Existing models for hBN have limitations in capturing defect energies and dynamics.
Purpose of the Study:
- To develop an accurate computational model for simulating hBN, including defect energies and dynamics.
- To investigate the influence of various atomic defects on the rippling and corrugation of hBN sheets.
- To compare the defect-induced dynamics in hBN with those in graphene.
Main Methods:
- Development of a machine learning-based Atomic Cluster Expansion (ACE) potential for hBN.
- Atomistic simulations using the developed ACE potential to model defect structures and dynamics.
- Analysis of defect concentration-dependent changes in surface roughness and rippling.
Main Results:
- A new, more stable defect structure in hBN consisting of a triplet of square-octagon (4|8) defects was predicted.
- A crossover in rippling behavior was observed with increasing defect density, transitioning from random rippling to fixed corrugation.
- Stone-Wales (5|7) defects were found to have the most significant impact on hBN rippling, unlike in graphene where divacancies dominate.
Conclusions:
- The study introduces a novel ACE potential for accurate hBN simulations, capturing defect properties.
- Atomic defects significantly influence hBN's surface dynamics, with Stone-Wales defects playing a key role.
- Material-specific defect engineering in hBN can be used to tune its properties for applications in nanoelectronics and membranes.
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