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First-principles calculation of the temperature dependence of the optical response of bulk GaAs

95   0   0.0 ( 0 )
 Added by Z. A. Ibrahim
 Publication date 2007
  fields Physics
and research's language is English
 Authors Z. A. Ibrahim




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A novel approach has been developed to calculate the temperature dependence of the optical response of a semiconductor. The dielectric function is averaged over several thermally perturbed configurations that are extracted from molecular dynamic simulations. The calculated temperature dependence of the imaginary part of the dielectric function of GaAs is presented in the range from 0 to 700 K. This approach that explicitly takes into account lattice vibrations describes well the observed thermally-induced energy shifts and broadening of the dielectric function.

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