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Saturated Low-Temperature Conductivity in Ultrafast Semiconductor Nanocomposites

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 نشر من قبل Weidong Zhang
 تاريخ النشر 2013
  مجال البحث فيزياء
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This article presents studies on low-field electrical conduction in the range 4-to-300 K for a ultrafast material: InGaAs:ErAs grown by molecular beam epitaxy. The unique properties include nano-scale ErAs crystallines in host semiconductor, a deep Fermi level, and picosecond ultrafast photocarrier recombination. As the temperature drops, the conduction mechanisms are in the sequence of thermal activation, nearest-neighbor hopping, variable-range hopping, and Anderson localization. In the low-temperature limit, finite-conductivity metallic behavior, not insulating, was observed. This unusual conduction behavior is explained with the Abrahams scaling theory.



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