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arXiv · 1101.1733

Low temperature reflectivity study of ZnO/(Zn,Mg)O quantum wells grown on M-plane ZnO substrates

Luc Beaur·Thierry Bretagnon·Christelle Brimont·Thierry Guillet·Bernard Gil·Dimitri Tainoff·M. Teisseire·J. M. Chauveau
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Abstract

We report growth of high quality ZnO/Zn0.8Mg0.2O quantum well on M-plane oriented ZnO substrates. The optical properties of these quantum wells are studied by using reflectance spectroscopy. The optical spectra reveal strong in-plane optical anisotropies, as predicted by group theory, and marked reflectance structures, as an evidence of good interface morphologies. Signatures ofc onfined excitons built from the spin-orbit split-off valence band, the analog of exciton C in bulk ZnO are detected in normal incidence reflectivity experiments using a photon polarized along the c axis of the wurtzite lattice. Experiments performed in the context of an orthogonal photon polarization, at 90^{\circ}; of this axis, reveal confined states analogs of A and B bulk excitons. Envelope function calculations which include excitonic interaction nicely account for the experimental report.

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Luc Beaur, Thierry Bretagnon, Christelle Brimont, Thierry Guillet, Bernard Gil, Dimitri Tainoff, M. Teisseire, J. M. Chauveau. 2011-10-17. Low temperature reflectivity study of ZnO/(Zn,Mg)O quantum wells grown on M-plane ZnO substrates. https://doi.org/10.1063/1.3565969

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