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arXiv · 2609.34872

Optimization of InAs/InAlGaAs/InP quantum dots for O-band laser applications

Anna Penkała·Paweł Podemski·Vinayakrishna Joshi·Vitalii Sichkovskyi·Johann P. Reithmaier·Grzegorz Sęk
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Abstract

The O-band telecommunication spectral range combines minimal chromatic dispersion with low transmission loss, making it highly suitable for optical communications. Semiconductor telecom lasers utilizing low-dimensional active regions, such as quantum dots, offer low threshold power and high thermal stability. However, long-wavelength quantum dot emitters often suffer from thermal carrier escape through excited states when the energy separation between the ground and excited states is insufficient. Here we demonstrate the optimization of InAs quantum dot emitters grown on InP by molecular-beam epitaxy for O-band laser active regions. By optimizing the design for better carrier capture efficiency and tuning the emission wavelength to the O-band, we show ways of improving the carrier confinement. Absorption spectroscopy on the finalized structure confirms substantial energy separation between the quantum dot ground and excited states, effectively suppressing thermal carrier escape even at elevated temperatures. These results highlight critical design for improving carrier capture and retention in long-wavelength quantum dot lasers.

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Anna Penkała, Paweł Podemski, Vinayakrishna Joshi, Vitalii Sichkovskyi, Johann P. Reithmaier, Grzegorz Sęk. 2026-09-28. Optimization of InAs/InAlGaAs/InP quantum dots for O-band laser applications. https://arxiv.org/abs/2609.34872

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