Interdot excitation transfer and spectral di usion: consequences of wetting layer potential uctuations in self-assembled quantum dots
نویسندگان
چکیده
A thin quantum well called the wetting layer is created whenever self-assembled quantum dots are fabricated. The wetting layer is highly non-uniform, thereby producing potential uctuations that in uence the physics of the quantum dots. Here, we report several e ects that are caused by such uctuations. In particular, light-induced spectral di usion on a very long time scale and interdot excitation transfer are observed in a sample of InAlAs quantum dots. We show that the existence of both these phenomena is due to the wetting layer uctuations. ? 2000 Elsevier Science B.V. All rights reserved. PACS: 73.23.Dx; 78.66.Fd; 78.55.Cr
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