Physical Review B 83, 241402(R) (2011)

Factors influencing the distribution of charge in polar nanocrystals

Philip W. Avraam, Nicholas D. M. Hine, Paul Tangney and Peter D. Haynes

Department of Physics and Department of Materials, Imperial College London, Exhibition Road, London SW7 2AZ, United Kingdom


We perform first-principles calculations of wurtzite GaAs nanorods to explore the factors determining the charge distribution in polar nanostructures. We show that both the direction and magnitude of the dipole moment d of a nanorod, and the electic field, depend sensitively on how its surfaces are terminated and not strongly on the spontaneous polarization of the underlying lattice. We identify two physical mechanisms by which d is controlled by the surface termination, and we show that the excess charge on the nanorod ends is not strongly localized. We discuss the implications of these results for tuning nanocrystal properties, and for their growth and assembly.


Last updated: 2 June 2011