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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Experimental studies of vibrational modes in a two-dimensional amorphous solid
Ling Zhang1, Jie Zheng1, Yinqiao Wang1
1School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China.
Nature Communications
|July 12, 2017
Summary
The boson peak in glasses is linked to spatial variations in shear modulus. This study reveals similar boson peak characteristics in a 2D granular system and 3D molecular glasses, suggesting a common origin related to material heterogeneity.
Area of Science:
- Condensed matter physics
- Materials science
- Complex systems
Background:
- The boson peak, an excess of vibrational states in glasses at low frequencies, has a controversial origin.
- Understanding the boson peak is crucial for characterizing glass properties.
Purpose of the Study:
- To investigate the nature of the boson peak by examining spatial heterogeneity of modulus fluctuations.
- To explore the relationship between the boson peak and material heterogeneity in a model system.
Main Methods:
- Utilized a highly jammed two-dimensional granular material as a model system.
- Analyzed the spatial heterogeneity of shear modulus fluctuations within the granular system.
Main Results:
- Observed a boson peak in the 2D granular system with a shape similar to that in 3D molecular glasses.
- Demonstrated a strong correlation between the boson peak and spatial heterogeneity of shear modulus fluctuations.
Conclusions:
- The boson peak's characteristics are strongly linked to spatial heterogeneity of shear modulus fluctuations.
- Findings suggest a universal mechanism for the boson peak across different glassy systems.
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