Charge controlled self-assembled quantum dots coupled to photonic crystal nanocavities

The system of charge controlled self-assembled quantum dots coupled to high-Q photonic crystal cavity modes is studied. The quantum dots are embedded in a p-i-n diode structure. Different designs of photonic crystal cavities are used, namely H1 and L3 and the Purcell effect is demonstrated. Furthermore, the fine tuning of the H1 cavity design is studied in order to achieve far field emission profiles that result in higher collection efficiency. An increase in the overall signal from the quantum dot when it is coupled to a cavity is observed, due to the Purcell effect and the improved collection efficiency. This together with the deterministic charging of the quantum dot that is demonstrated, can be used for a single electron spin measurement.