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-assembled 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 of states is presented. As a result, the density of the dots, the excitation energy of electrons and its dispersion were obtained and found to be in good agreement with the photoluminescence data.