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

We present a pseudopotential approach to the calculation of the excitonic s pectrum of semiconductor quantum dots. Starting from a many-body expansion of the exciton wave functions in terms of single-substitution Slater determ inants constructed from pseudopotential single-particle wave functions, our method permits an accurate and detailed treatment of the intraconfiguratio n electron-hole Coulomb and exchange interactions, while correlation effect s can be included in a controlled fashion by allowing interconfiguration co upling. We calculate the exciton fine structure of InP and CdSe nanocrystal s in the strong-confinement regime. We find a different size dependence for the electron-hole exchange interaction than previously assumed (i.e., R-2 instead of R-3). Our calculated exciton fine structure is compared with rec ent experimental results obtained by size-selective optical spectroscopies. [S0163-1829(99)00227-1].