Capacitance-voltage profile in a structure with negative differential capacitance caused by the presence of InAs/GaAs self-assembled quantum dots

The application of the usual expressions to calculate the capacitance-voltage (CV) profiles in samples with quantum dots gives erroneous results, mainly due to the presence of the characteristic negative differential capacitance of a system with dimensionality lower than 2. We developed a simple electrostatic model to calculate the CV profiles in these systems, and we applied it to a sample with an InAs self-assembled quantum dots system in order to obtain informations about the structure of the dots. As a result, the local distribution of electrons in the quantum dots (CV profile) was obtained.