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arXiv · 1012.3710

Photoluminescence of patterned arrays of vertically stacked InAs/GaAs quantum dots

T. W. Saucer·J. -E. Lee·A. J. Martin·D. Tien·J. M. Millunchick·V. Sih
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Abstract

We report on photoluminescence measurements of vertically stacked InAs/GaAs quantum dots grown by molecular-beam epitaxy on focused ion beam patterned hole arrays with varying array spacing. Quantum dot emission at 1.24 eV was observed only on patterned regions, demonstrating preferential nucleation of optically-active dots at desired locations and below the critical thickness for dot formation at these growth conditions. Photoluminescence measurements as a function of varying focused ion beam irradiated hole spacing showed that the quantum dot emission intensity increased with decreasing array periodicity, consistent with increasing dot density.

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T. W. Saucer, J. -E. Lee, A. J. Martin, D. Tien, J. M. Millunchick, V. Sih. 2010-12-16. Photoluminescence of patterned arrays of vertically stacked InAs/GaAs quantum dots. https://doi.org/10.1016/j.ssc.2010.12.020

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