Computer simulation of low-energy excitations in amorphous silicon with voids
نویسندگان
چکیده
We use empirical molecular dynamics technique to investigate the low-energy vibrations in a large 4096 atom model for pure amorphous silicon and a set of models with voids of dierent size based on it. Numerical vibrational eigenvalues and eigenvectors for our models are obtained by exact diagonalization of their dynamical matrices. Our calculations show that localized low-energy vibrational excitations of rather complex structure are present in amorphous silicon models with voids. According to their spatial localization patterns we make an attempt to classify these excitations as modes associated with the void and `mixed' modes associated with the interaction of the void with strained regions of silicon network. Ó 2000 Elsevier Science B.V. All rights reserved.
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