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Electrons and Phonons in amorphous Si: Deformation Potentials and Solutions of the Time Dependent Schrödinger Equation

Published online by Cambridge University Press:  01 February 2011

D. A. Drabold
Affiliation:
Department of Physics and Astronomy, Nanoscale and Quantum Phenomena Institute, Ohio University, Athens, OH 45701, U.S.A.
Jun Li
Affiliation:
Department of Physics and Astronomy, Nanoscale and Quantum Phenomena Institute, Ohio University, Athens, OH 45701, U.S.A.
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Abstract

We employ first principles methods to explore the coupling between electrons and the lattice in amorphous silicon (a-Si). First we compute the adiabatic electronic response to phonon modes in a realistic model of a-Si. Then, we present a simulation of the electron dynamics of localized edge states in a-Si at room temperature by integrating the time dependent Schrödinger equation. We study the character of the spatial and spectral diffusion of the localized states and directly simulate and reveal the nature of thermally driven hopping. Phonon-induced resonant mixing leads to rapid electronic diffusion if states are available nearby in energy and real-space. We believe that many of the results we obtain are central to modeling transport involving localized states.

Type
Research Article
Copyright
Copyright © Materials Research Society 2002

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