Recently, a simple method has been developed to obtain inverted GaAs/AlGaAs quantum dots (QDs) below a quantum well (QW) via multi-step (hierarchical) self-assembly . Here we report on the optical characterization of a series of structures GaAs QDs with different size. The study is performed by means of reflectance (R) down to T=15 K, photo- and thermo-reflectance (T>80 K) and by spectroscopic ellipsometry (at RT). Such measurements allow us to check the thickness and composition of the barrier layers and to complete the study of the electronic states involved in the emission properties of QDs and QW levels. QW states were well identified and their energies and shift with the size parameters well agree with the photoluminescence (PL) data. The identification of QD states seems less straightforward in R measurements and deserves further investigation.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
A. Rastelli et al., Phys. Rev. Lett. 92, 166104 (2004).
U. Denker, M. Stoffel, and O.G. Schmidt, Phys. Rev. Lett. 90, 196102 (2003).
R. Songmuang, S. Kiravittaya, and O.G. Schmidt, Appl. Phys. Lett. 82, 2892 (2003).
S. Kiravittaya et al., J. Cryst. Growth 251, 258 (2003).
About this article
Cite this article
Marabelli, F., Rastelli, A., Schmidt, O.G. et al. Optical characterization of hierarchically self-assembled GaAs/AlGaAs quantum dots. MRS Online Proceedings Library 829, 124–129 (2004). https://doi.org/10.1557/PROC-829-B1.7