Excitonic properties of ultrathin quantum dots

This book presents a theoretical study of the optical and excitonic properties of an exciton confined in discoidal quantum dots (QDs), taking into account the effects of quantum confinement, hydrostatic pressure and temperature. The analysis is based on the variational method, effective mass theory and the envelope function. After an introduction to the fundamental concepts of semiconductors and nanostructures, the book examines the impact of confinement on energy levels and optical properties. The study of linear and non-linear exciton properties reveals that a reduction in the size of BQs enhances confinement, increases the exciton binding energy and causes a blue shift in the absorption spectra. The combined effect of pressure and temperature is also analysed: pressure accentuates electron-hole interaction, while temperature and enlargement of BQs induce a red shift. Two simple analytical relationships describe the evolution of the binding energy as a function of these parameters.