Energetics and carrier transport in doped Si/SiO2 quantum dots.

In the present theoretical work we have considered impurities, either boron or phosphorous, located at different substitutional sites in silicon quantum dots (Si-QDs) with diameters around 1.5 nm, embedded in a SiO2 matrix. Formation energy calculations reveal that the most energetically-favored doping sites are inside the QD and at the Si/SiO2 interface for P and B impurities, respectively.

Polarity-driven polytypic branching in cu-based quaternary chalcogenide nanostructures.

An appropriate way of realizing property nanoengineering in complex quaternary chalcogenide nanocrystals is presented for Cu2CdxSnSey(CCTSe) polypods. The pivotal role of the polarity in determining morphology, growth, and the polytypic branching mechanism is demonstrated. Polarity is considered to be responsible for the formation of an initial seed that takes the form of a tetrahedron with four cation-polar facets.