Dynamics of Carrier Transport in Nanoscale Materials: Origin of Non-Drude Behavior in the Terahertz Frequency Range

نویسندگان

  • Koichi Shimakawa
  • Safa Kasap
  • Takayoshi Kobayashi
چکیده

It is known that deviation from the Drude law for free carriers is dramatic in most electronically conductive nanomaterials. We review recent studies of the conductivity of nanoscale materials at terahertz (THz) frequencies. We suggest that among a variety of theoretical formalisms, a model of series sequence of transport involving grains and grain boundaries provides a reasonable explanation of Lorentz-type resonance (non-Drude behavior) in nanomaterials. Of particular interest is why do free carriers exhibit a Lorentz-type resonance.

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تاریخ انتشار 2016