title: Direct quantitative electrical measurement of many-body interactions in exciton complexes in InAs quantum dots.
abstract: We present capacitance-voltage spectra for the conduction band states of InAs quantum dots obtained under continuous illumination. The illumination leads to the appearance of additional charging peaks that we attribute to the charging of electrons into quantum dots containing a variable number of illumination-induced holes. By this we demonstrate an electrical measurement of excitonic states in quantum dots. Magnetocapacitance-voltage spectroscopy reveals that the electron always tunnels into the lowest electronic state. This allows us to directly extract, from the highly correlated many-body states, the correlation energy. The results are compared quantitatively to state of the art atomistic configuration interaction calculations, showing very good agreement for a lower level of excitations and also limitations of the approach for an increasing number of particles. Our experiments offer a rare benchmark to many-body theoretical calculations.
authors.affiliation: Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, Universitätsstraße 150, D-44780 Bochum, Germany.
authors.forename: P A
authors.initials: PA
authors.lastname: Labud
authors.affiliation: Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, Universitätsstraße 150, D-44780 Bochum, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Ludwig
authors.affiliation: Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, Universitätsstraße 150, D-44780 Bochum, Germany.
authors.forename: A D
authors.initials: AD
authors.lastname: Wieck
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569 Stuttgart, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Bester
authors.affiliation: Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, Universitätsstraße 150, D-44780 Bochum, Germany and Department Physik, Universität Paderborn, Warburger Straße 100, D-33098 Paderborn, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Reuter