Controlling the electronic structure of nanocrystal assemblies by variation of the particle-particle interaction

Lawrence Livermore National Laboratory, Livermore, California, United States
Applied Physics Letters (Impact Factor: 3.3). 09/2004; 85(22):5334-5336. DOI: 10.1063/1.1828238


The change in the electronic structure of germanium nanocrystals is investigated as their concentration is increased from noninteracting, individual particles to assembled arrays of particles. The electronic structure of the individual nanoclusters shows clear effects due to quantum confinement which are lost in the concentrated assemblies of bare particles. When the surface of the individual particles is passivated, they retain their quantum confinement properties also upon assembly. These effects are interpreted in terms of a particle-particle interaction model. (C) 2004 American Institute of Physics.

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    • "An especially interesting system is a Ge QD lattice embedded in amorphous alumina (Al 2 O 3 ) matrix. Ge shows a very strong carrier confinement, and therefore the electronic properties of Ge QDs are strongly tunable by changing their sizes (Bostedt et al. 2004). Ge QDs also exhibit electro-and photoluminescence, non-linear optical properties; they are capable to retain electric charge for a long time and have unusual melting-freezing conditions (Shen et al. 2002; Maeda 1995; Dowd et al. 1999; Xu et al. 2006; Kanjilal et al. 2003; Chang et al. 2004). "
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