Prepositioned single quantum dot in a lateral electric field

We examine the effect of a lateral electric field on the optical properties of a single deterministically positioned InAs/InP quantum dot. We show experimentally that the ground-state excitonic Stark shift is significantly reduced in comparison with the single-particle picture and that the lateral electric field introduces a new previously forbidden optical transition. Results of full configuration-interaction calculations show that the Coulomb interactions of electrons and holes are modified by the electric field leading to the compensation of the single-particle Stark shift. The calculations also account for the appearance of the field-activated optical transition as an excitonic recombination event. The comparison of exciton and predicted charged exciton spectra allows us to exclude the presence of charged exciton complexes within the measured emission spectra. The ability to precisely position a single quantum dot and demonstrate control over the electronic properties of such a dot is expected to find application in scalable techniques for quantum information science.