Charging of embedded InAs self-assembled quantum dots by space-charge techniques - art. no. 125315

We present the results of both electrical and optical investigations of the charging of InAs self-assembled quantum dots embedded in a space-charge st ructure. Admittance spectroscopy was employed to study the electronic struc tures in quantum dots and their electron escape mechanisms. We resolved cle ar conductance features of different quantum-dot shells, enabling the study of electrons that escaped separately from different shells. Electron-filli ng modulation reflectance was used to investigate the interband transition influenced by the charging effects. Both the strengths and the energies of the interband transitions were modified in accordance with the electron occ upation due to Pauli-blocking and the Coulomb-charging effects. The informa tion acquired from these experimental observations is valuable for feasible device applications.