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arXiv · 1011.6177

Dielectric confinement of excitons in type-I and type-II semiconductor nanorods

Miquel Royo·Juan Ignacio Climente·José Luis Movilla·Josep Planelles
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Abstract

We theoretically study the effect of the dielectric environment on the exciton ground state of CdSe and CdTe/CdSe/CdTe nanorods. We show that insulating environments enhance the exciton recombination rate and blueshift the emission peak by tens of meV. These effects are particularly pronounced for type-II nanorods. In these structures, the dielectric confinement may even modify the spatial distribution of electron and hole charges. A critical electric field is required to separate electrons from holes, whose value increases with the insulating strength of the surroundings.

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Miquel Royo, Juan Ignacio Climente, José Luis Movilla, Josep Planelles. 2010-11-29. Dielectric confinement of excitons in type-I and type-II semiconductor nanorods. https://doi.org/10.1088/0953-8984%2F23%2F1%2F015301

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