Observation of an electrically tunable exciton g factor in InGaAs/GaAs quantum dots

The electric field dependence of the exciton g factor and the fine structure splitting in self-assembled InGaAs/GaAs quantum dots grown via a flush-overgrowth technique is studied by photocurrent and photoluminescence experiments. Both the fine structure and the Zeeman splitting can be tuned over a wide range via electric fields applied in growth direction of the quantum dot. For the g factor, a tunability of 250% is demonstrated from g=0.12 to 0.42.