Hole-capture competition between a single quantum dot and an ionized acceptor

We study the competition of hole capture between an In(Ga)As quantum dot and a directly adjacent ionized impurity in view of spin-photon interfaces. The Kerr rotation noise spectroscopy at 4.2 K shows that the hole-capture probability of the In(Ga)As quantum dot is about one order of magnitude higher compared to the hole-capture probability of the ionized impurity and suggests that a simultaneous occupation of quantum dot and impurity by a hole is efficiently suppressed due to Coulomb interaction. A theoretical model of interconnected spin and charge noise allows the quantitative specification of all relevant time scales.