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arXiv · 1102.4490

Strain balanced quantum posts

D. Alonso-Álvarez·B. Alén·J. M. Ripalda·J. Llorens·A. G. Taboada·F. Briones·M. A. Roldán·J. Hernández-Saz·D. Hernández-Maldonado·M. Herrera·S. I. Molina
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Abstract

Quantum posts are assembled by epitaxial growth of closely spaced quantum dot layers, modulating the composition of a semiconductor alloy, typically InGaAs. In contrast with most self-assembled nanostructures, the height of quantum posts can be controlled with nanometer precision, up to a maximum value limited by the accumulated stress due to the lattice mismatch. Here we present a strain compensation technique based on the controlled incorporation of phosphorous, which substantially increases the maximum attainable quantum post height. The luminescence from the resulting nanostructures presents giant linear polarization anisotropy.

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D. Alonso-Álvarez, B. Alén, J. M. Ripalda, J. Llorens, A. G. Taboada, F. Briones, M. A. Roldán, J. Hernández-Saz, D. Hernández-Maldonado, M. Herrera, S. I. Molina. 2011-03-07. Strain balanced quantum posts. https://doi.org/10.1063/1.3583455

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