A quantum dot nucleated on the edge of a threading dislocation: elastic and electric field effects

Abstract

AbstractIn this work the affect of a threading dislocation localised on the edge of GaN/AlN quantum dot is analysed. A standard piezoelectric continuum model is extended to allow the embodiment of threading dislocations that are modelled as a continuous electro‐elastic line defect originating in the matrix material. Two common types of dislocation are considered: an edge‐type and a screw‐type.It is demonstrated that the presence of a TD provides local region of tensile strain as a preferential condition for GaN QD growth by reduction of the GaN / AlN lattice mismatch. It is found that dislocation induced potential causes a measurable in‐plane shift of the electron/hole localisation and an asymmetric decrease in the band‐to‐band transition energy. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)