Atomic and electronic structure of misfit dislocations in GaSb/GaAs(001)

We investigated the atomic and electronic structures of the periodic misfit dislocations (MDs) found in GaSb/GaAs (0 0 1). In order to determine the details of these structures, we carried out the first-principle total energy calculations. The characteristic feature in the MDs is the appearance of the anion-anion or cation-cation bond in order to avoid the formation of dangling bonds. As a result, the dislocation core structure form five- and seven-membered rings. These MDs electronically cause the impurity levels in the band gap. The individual MDs have the possibility to form one-dimensional electron- and hole-paths along the dislocation line. (C) 2003 Elsevier B.V. All rights reserved.