Investigation of the InAs/GaAs self-assembled quantum dots using the relationship between the capacitance and the density of states

A negative differential capacitance observed in the InAs/GaAs self-assemble d quantum dots is shown to be an essential feature of the zero-dimensional electron system. A direct link of the capacitance to the electron density o f states is presented. As a result, the density of the dots, the excitation energy of electrons and its dispersion were obtained and found to he in go od agreement with the photoluminescence data. (C) 2001 Elsevier Science B.V . All rights reserved.