Year: 2017
Type: article
Abstract: We present a description of vacuum polarization in a circular Dirac quantum dot in two spatial dimensions assuming $\ensuremath{\alpha}$---the relative strength of the Coulomb interaction small enough to render an approximation with a single electron (hole) lowest energy level relevant. Applying this approximation, we find that for ${\ensuremath{\alpha}}_{c}\ensuremath{\approx}1.05$ the lowest level is half filled irrespective of the number of flavors that are present. The ground state can be represented as a superposition of particular (even number) excitonic states which constitute an excitonic cloud that evolves in a crossover manner. The ground state is degenerate with an intervalley excitonic state at ${\ensuremath{\alpha}}_{c}\ensuremath{\approx}1.05$, a critical strength, that in our approximation marks a point with single electron and exciton resonances.
Authors: V. Raca, M. V. Milovanović
Institutions: University of Belgrade, Institute of Physics Belgrade
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Award: G7412154610
OpenAlex ID: W2769181017