Physics – Condensed Matter – Disordered Systems and Neural Networks
Scientific paper
2003-01-14
Phys. Rev. B 67, 224302 (2003)
Physics
Condensed Matter
Disordered Systems and Neural Networks
9 two-column pages, 13 figures
Scientific paper
10.1103/PhysRevB.67.224302
The anharmonic decay rates of atomic vibrations in amorphous silicon (a-Si) and paracrystalline silicon (p-Si), containing small crystalline grains embedded in a disordered matrix, are calculated using realistic structural models. The models are 1000-atom four-coordinated networks relaxed to a local minimum of the Stillinger-Weber interatomic potential. The vibrational decay rates are calculated numerically by perturbation theory, taking into account cubic anharmonicity as the perturbation. The vibrational lifetimes for a-Si are found to be on picosecond time scales, in agreement with the previous perturbative and classical molecular dynamics calculations on a 216-atom model. The calculated decay rates for p-Si are similar to those of a-Si. No modes in p-Si reside entirely on the crystalline cluster, decoupled from the amorphous matrix. The localized modes with the largest (up to 59%) weight on the cluster decay primarily to two diffusons. The numerical results are discussed in relation to a recent suggestion by van der Voort et al. [Phys. Rev. B {\bf 62}, 8072 (2000)] that long vibrational relaxation inferred experimentally may be due to possible crystalline nanostructures in some types of a-Si.
Fabian Jaroslav
Feldman Joseph L.
Hellberg Stephen C.
Nakhmanson Serge M.
No associations
LandOfFree
Numerical study of anharmonic vibrational decay in amorphous and paracrystalline silicon does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Numerical study of anharmonic vibrational decay in amorphous and paracrystalline silicon, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Numerical study of anharmonic vibrational decay in amorphous and paracrystalline silicon will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-220092