Demonstration of strong coupling via electro-optical tuning in high-quality QD-micropillar systems.

We demonstrate electro-optical tuning of single quantum dots (QDs) embedded in high-quality (high-Q) micropillar cavities by exploiting the quantum confined Stark effect (QCSE). Combining electrically contacted high-Q micropillars and large In(0.3) Ga(0.7)As QDs with high oscillator strength facilitates the realization of strong coupling. In our experiments a single QD exciton was electrically tuned on resonance with a cavity mode of a micropillar with 1.9 microm diameter and a quality-factor (Q-factor) of 14,000 enabling the observation of strong coupling with a vacuum Rabi-Splitting of 63 microeV.