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Vibrational properties of amorphous silicon from tight-binding O(N) calculation

Parthapratim Biswas
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Abstract

We present an O(N) algorithm to study the vibrational properties of amorphous silicon within the framework of tight-binding approach. The dynamical matrix elements have been evaluated numerically in the harmonic approximation exploiting the short-range nature of the density matrix to calculate the vibrational density of states which is then compared with the same obtained from a standard O($N^4$) algorithm. For the purpose of illustration, an 1000-atom model is studied to calculate the localization properties of the vibrational eigenstates using the participation numbers calculation.

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Parthapratim Biswas. 2002-01-16. Vibrational properties of amorphous silicon from tight-binding O(N) calculation. https://doi.org/10.1103/physrevb.65.125208

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