Electrical tuning of the g factor of single self-assembled quantum dots

The g factor of a single self-assembled quantum dot is tuned by applying an electrical bias voltage. Individual InGaAs quantum dots embedded in a stripe mesa structure sandwiched by Schottky electrodes are studied by photoluminescence measurements. We find that under applied magnetic field a dot with an asymmetric shift for applied bias voltage shows an increase of the exciton g-factor absolute value by about 8%, while most of the dots with relatively symmetric shifts show no significant change. The anomalous g-value increase is discussed in terms of the Kondo effect.