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Updated: Nov 20, 2025
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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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Excitations of atomic vibrations in amorphous solids.
1Department of Physics, Wenzhou University, Wenzhou 325035, People's Republic of China.
Summary
This study analyzes atomic vibrations in amorphous solids, revealing collective and local excitations. Collective vibrations show periodic structures, while local excitations have complex wave vectors related to their decay length and frequency.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Solid-State Physics
Background:
- Amorphous solids lack long-range order, making atomic vibration analysis complex.
- Understanding atomic vibrations is crucial for material properties and dynamics.
Purpose of the Study:
- To investigate atomic vibration excitations in the reciprocal space of amorphous solids.
- To characterize collective and local excitations and their properties.
Main Methods:
- Introduction of a continuous wave vector.
- Transformation of atomic vibration equations from real space to reciprocal space.
- Analysis of amorphous silicon as a model system.
Main Results:
- Atomic excitations are identified as wave packets of plane waves.
- Collective excitations in amorphous solids exhibit periodic reciprocal space structures.
- Local excitations possess complex wave vectors, with decay length inversely related to frequency.
Conclusions:
- The study provides a framework for analyzing atomic vibrations in amorphous materials.
- Reciprocal space analysis reveals distinct characteristics of collective and local excitations.
- The findings offer insights into the relationship between local atomic order and vibrational properties.
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