title: Real space pseudopotential calculations for size trends in Ga- and Al-doped zinc oxide nanocrystals with wurtzite and zincblende structures.
abstract: Zinc oxide is often used as a popular inexpensive transparent conducting oxide. Here, we employ density functional theory and local density approximation to examine the effects of quantum confinement in doped nanocrystals of this material. Specifically, we examine the addition of Ga and Al dopants to ZnO nanocrystals on the order of 1.0 nm. We find that the inclusion of these dopants is energetically less favorable in smaller particles and that the electron binding energy, which is associated with the dopant activation, decreases with the nanocrystal size. We find that the introduction of impurities does not alter significantly the Kohn-Sham eigenspectrum for small nanocrystals of ZnO. The added electron occupies the lowest existing state, i.e., no new bound state is introduced in the gap. We verify this assertion with hybrid functional calculations.
authors.affiliation: Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: N Scott
authors.initials: NS
authors.lastname: Bobbitt
authors.affiliation: Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Na
authors.initials: N
authors.lastname: Sai
authors.affiliation: Department of Physics and Engineering Physics, Tulane University, New Orleans, Louisiana, 70118 USA.
authors.forename: Noa
authors.initials: N
authors.lastname: Marom
authors.affiliation: Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Minjung
authors.initials: M
authors.lastname: Kim
authors.affiliation: Center for Computational Materials, Institute for Computational Engineering and Sciences, Departments of Physics and Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: James R
authors.initials: JR
authors.lastname: Chelikowsky