Enhanced carrier confinement in quantum dots by raising wetting layer state energy

Moehl, Sebastian; Maingault, Laurent; Kheng, Kuntheak; Mariette, Henri
July 2005
Applied Physics Letters;7/18/2005, Vol. 87 Issue 3, p033111
Academic Journal
A quantum dot design is proposed where the wetting layer states are shifted to higher energies. It is realized by including CdTe quantum dots between two thin MgTe layers. As both materials have nearly the same lattice parameter, the first MgTe layer forms a wetting layer with high carrier state energy. Consequently, the radiative regime of the dots is significantly extended to higher temperatures. The unusual temperature-dependence of the decay time is discussed using a model for localized and delocalized states.


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