Eur. Phys. J. B (2013) 86: 449
https://doi.org/10.1140/epjb/e2013-40542-0

Regular Article

Interplay between Coulomb interaction and quantum-confined Stark-effect in polar and nonpolar wurtzite InN/GaN quantum dots

¹ Institute for Theoretical Physics, University of Bremen, 28359 Bremen, Germany
² Paul-Drude-Institut für Festkörperelektronik, 10117 Berlin, Germany
³ Max-Planck Institut für Eisenforschung, 40237 Düsseldorf, Germany

^a e-mail: sbarthel@itp.uni-bremen.de

Received: 3 June 2013
Received in final form: 17 September 2013
Published online: 1 November 2013

Abstract

In this paper we systematically analyze the electronic structures of polar and nonpolar wurtzite-InN/GaN quantum dots and their modification due to the quantum-confined Stark effect caused by intrinsic fields. This is achieved by combining continuum elasticity theory with an effective-bond orbital model to describe the elastic and single-particle electronic properties in these nitride systems. Based on these results, a many-body treatment is used to determine optical absorption spectra. The efficiency of optical transitions depends on the interplay between the Coulomb interaction and the quantum-confined Stark effect. We introduce an effective confinement potential which represents the electronic structure under the influence of the intrinsic polarization fields and calculate the needed strength of Coulomb interaction to diminish the separation of electrons and holes.