Approximate ab initio calculation of vibrational properties of hydrogenated amorphous silicon with inner voids

Serge M. Nakhmanson; D. A. Drabold

doi:10.1103/physrevb.58.15325

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Approximate ab initio calculation of vibrational properties of hydrogenated amorphous silicon with inner voids

Serge M. Nakhmanson·D. A. Drabold

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Abstract

We have performed an approximate ab initio calculation of vibrational properties of hydrogenated amorphous silicon (a-Si:H) using a molecular dynamics method. A 216 atom model for pure amorphous silicon (a-Si) has been employed as a starting point for our a-Si:H models with voids that were made by removing a cluster of silicon atoms out of the bulk and terminating the resulting dangling bonds with hydrogens. Our calculation shows that the presence of voids leads to localized low energy (30-50 cm^{-1}) states in the vibrational spectrum of the system. The nature and localization properties of these states are analyzed by various visualization techniques.

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Serge M. Nakhmanson, D. A. Drabold. 1998-10-17. Approximate ab initio calculation of vibrational properties of hydrogenated amorphous silicon with inner voids. https://doi.org/10.1103/physrevb.58.15325

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