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arXiv · 1111.1526

Effect of interface alloying and band-alignment on the Auger recombination of heteronanocrystals

J. I. Climente·J. L. Movilla·J. Planelles
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Abstract

We report a numerical study of the effect of interface alloying and band-alignment on the Auger recombination processes of core/shell nanocrystals. Numerical calculations are carried out using a two-band Kane Hamiltonian. Smooth interfaces are found to suppress Auger recombination, the strength of the suppression being very sensitive to the core size. The use of type-II structures constitutes an additional source of suppression, especially when the shell confines electrons rather than holes. We show that "magic" sizes leading to negligible Auger recombination [Cragg and Efros, Nano Letters 10 (2010) 313] should be easier to realize experimentally in nanocrystals with extended interface alloying and wide band gap.

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J. I. Climente, J. L. Movilla, J. Planelles. 2011-11-07. Effect of interface alloying and band-alignment on the Auger recombination of heteronanocrystals. https://doi.org/10.1063/1.3684981

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