Microscopic dielectric response functions in semiconductor quantum dots.

نویسندگان

  • Xavier Cartoixà
  • Lin-Wang Wang
چکیده

We calculate and model the microscopic dielectric response function for quantum dots using first principle methods. We find that the response is bulklike inside the quantum dots, and the reduction of the macroscopic dielectric constants is a surface effect. We present a model for the microscopic dielectric function which reproduces well the directly calculated results and can be used to solve the Poisson equation in a nanosystem.

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عنوان ژورنال:
  • Physical review letters

دوره 94 23  شماره 

صفحات  -

تاریخ انتشار 2005