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Updated: Oct 3, 2025
10:35
Using Microwave and Macroscopic Samples of Dielectric Solids to Study the Photonic Properties of Disordered Photonic Bandgap Materials
Published on: September 26, 2014
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Spatially Resolved Band Gap and Dielectric Function in Two-Dimensional Materials from Electron Energy Loss
Abel Brokkelkamp1, Jaco Ter Hoeve2,3, Isabel Postmes1
1Kavli Institute of Nanoscience, Delft University of Technology, 2628CJ Delft, The Netherlands.
The Journal of Physical Chemistry. A
|February 15, 2022
Summary
This study introduces a machine learning method to precisely measure electronic properties like band gap in 2D materials. This technique offers nanometer-scale resolution for advanced material analysis.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Electronic properties of 2D materials are highly sensitive to atomic structure.
- Accurate characterization of these properties at the nanoscale is crucial for device applications.
Purpose of the Study:
- To develop a novel, automated strategy for determining the band gap and dielectric function of 2D materials with high spatial resolution.
- To apply machine learning techniques for processing and interpreting spectral imaging data.
Main Methods:
- Utilized machine learning algorithms, specifically K-means clustering and deep learning, for spectral image analysis.
- Applied Electron Energy Loss Spectroscopy (EELS) to capture spectral data.
- Developed an automated processing pipeline within the open-source EELSfitter framework.
Main Results:
- Achieved spatial resolution down to a few nanometers for electronic property determination.
- Successfully assessed the band gap and dielectric function of Indium Selenide (InSe) and Tungsten Disulfide (WS2) nanoflowers.
- Correlated measured electrical properties with local material thickness.
Conclusions:
- The developed machine learning approach enables precise, nanoscale characterization of 2D material electronic properties.
- The method is generalizable to various nanostructured materials and spectroscopic techniques.
- This work provides a powerful, automated tool for materials research.
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