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arXiv · 0710.5851

Realization of efficient electroabsorption using intersubband transitions in step quantum wells

P. Holmström·P. Jänes·U. Ekenberg·L. Thylén
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Abstract

We have demonstrated efficient intersubband electroabsorption in InGaAs/InAlGaAs/InAlAs step quantum wells grown by metal-organic vapor phase epitaxy (MOVPE). An absorption modulation of 6 dB at $λ=6.0 μ$m due to Stark shift of the IS absorption was achieved at a low voltage swing of $\pm 0.5$ V in a multipass waveguide structure. Based on the experimental results it is estimated that an electroabsorption modulator with a low peak-to-peak voltage of $V_{pp}=0.9$ V can yield a modulation speed of $f_{3dB} \approx 120$ GHz with the present material by using a strongly confining surface plasmon waveguide of 30 $μ$m length.

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P. Holmström, P. Jänes, U. Ekenberg, L. Thylén. 2007-10-31. Realization of efficient electroabsorption using intersubband transitions in step quantum wells. https://arxiv.org/abs/0710.5851

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