Vidar Gudmundsson

We don’t have enough information about this author to calculate their statistics. If you think this is an error let us know.
Learn More
We study Coulomb interacting electrons confined in polygonal quantum rings. We focus on the interplay of localization at the polygon corners and Coulomb repulsion. Remarkably, the Coulomb repulsion allows the formation of in-gap states, i.e., corner-localized states of electron pairs or clusters shifted to energies that were forbidden for non-interacting(More)
We compare energy levels, carrier localization and optical absorption of a single electron and a pair of interacting carriers confined in a hexagonal quantum ring. We show that many-body levels are multiple degenerate and, contrary to the single-particle case, no repeated energy sequence can be identified. The number of eigenvalues associated with(More)
We compare energy spectra, electron localization and optical absorption of square and diamond quantum rings and analyze how sample geometry affects those features. We show that low energy levels of diamond rings form two groups delocalized between opposite corners which results in increased number of optical transitions. We also show that contacts applied(More)
We investigate transient transport of electrons through a single quantum dot controlled by a plunger gate. The dot is embedded in a finite wire with length Lx assumed to lie along the x-direction with a parabolic confinement in the y-direction. The quantum wire, originally with hard-wall confinement at its ends, ±Lx/2, is weakly coupled at t = 0 to left and(More)
We outline a rigorous method which can be used to solve the many-body Schrödinger equation for a Coulomb interacting electronic system in an external classical magnetic field as well as a quantized electromagnetic field. Effects of the geometry of the electronic system as well as the polarization of the quantized electromagnetic field are explicitly taken(More)
We investigate the effects of the shape of quantum dots on their far-infrared absorption in an external magnetic field by a model calculation. We focus our attention on dots with a parabolic confinement potential deviating from the common circular symmetry, and dots having circular doughnut shape. For a confinement where the generalized Kohn theorem does(More)
  • 1