Recent advances in exciton-based quantum information processing in quantum dot nanostructures

Recent experimental developments in the field of semiconductor quantum dot (QD) spectroscopy are discussed. Firstly, we report about single QD exciton two-level systems and their coherent properties in terms of single-qubit manipulations. In the second part, we report on coherent quantum coupling in a prototype ‘two-qubit’ system consisting of a vertically stacked pair of QDs. The interaction can be tuned in such QD molecule devices using an applied voltage as external parameter.