Structural Origin of the Midgap Electronic States and the Urbach Tail in Pnictogen-Chalcogenide Glasses.

  title={Structural Origin of the Midgap Electronic States and the Urbach Tail in Pnictogen-Chalcogenide Glasses.},
  author={Alexey Lukyanov and John C. Golden and Vassiliy Lubchenko},
  journal={The journal of physical chemistry. B},
  volume={122 33},
We determine the electronic density of states for computationally generated bulk samples of amorphous chalcogenide alloys As xSe100- x. The samples were generated using a structure-building algorithm reported recently by us. Several key features of the calculated density of states are in good agreement with experiment: The trend of the mobility gap with arsenic content is reproduced. The sample-to-sample variation in the energies of states near the mobility gap is quantitatively consistent with… 
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