Single-electron charging in quantum dots with large dielectric mismatch

Semiconductor quantum dots characterized by a strong dielectric mismatch with their environment are studied theoretically through direct diagonalization of the many-body Hamiltonian. The enhancement of the electron-electron Coulomb interaction, arising from polarization effects, is found to induce a strong increase in addition energies with increasing dielectric mismatch. For large dielectric mismatch, the excited many-body states can undergo reconstructions as the dot is filled with carriers even in the absence of external magnetic fields.