Many-body pseudopotential theory of excitons in InP and CdSe quantum dots

نویسندگان

  • A. Franceschetti
  • H. Fu
  • L. W. Wang
  • A. Zunger
چکیده

We present a pseudopotential approach to the calculation of the excitonic spectrum of semiconductor quantum dots. Starting from a many-body expansion of the exciton wave functions in terms of singlesubstitution Slater determinants constructed from pseudopotential single-particle wave functions, our method permits an accurate and detailed treatment of the intraconfiguration electron-hole Coulomb and exchange interactions, while correlation effects can be included in a controlled fashion by allowing interconfiguration coupling. We calculate the exciton fine structure of InP and CdSe nanocrystals in the strong-confinement regime. We find a different size dependence for the electron-hole exchange interaction than previously assumed ~i.e., R instead of R). Our calculated exciton fine structure is compared with recent experimental results obtained by size-selective optical spectroscopies. @S0163-1829~99!00227-1#

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تاریخ انتشار 1999