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arXiv · 1811.03927

Synthesis and systematic optical investigation of selective area droplet epitaxy of InAs/InP quantum dots assisted by block copolymer lithography

Artem Shikin·Elizaveta Lebedkina·Czcibor Ciostek·Pawel Holewa·Sokol Ndoni·Kristoffer Aldmal·Kresten Yvind·Marcin Syperek·Elizaveta Semenova
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Abstract

We report on the systematic investigation of the optical properties of a selectively grown quantum dot gain material assisted by block-copolymer lithography for potential applications in active optical devices operating in the wavelength range around 1.55 um and above. We investigated a new type of diblock copolymer PS-b-PDMS (polystyrene-block-polydimethylsiloxane) for the fabrication of silicon oxycarbide hard mask for selective area epitaxy of InAs/InP quantum dots. An array of InAs/InP quantum dots was selectively grown via droplet epitaxy. Our detailed investigation of the quantum dot carrier dynamics in the 10-300 K temperature range indicates the presence of a density of states located within the InP bandgap in the vicinity of quantum dots. Those defects have a substantial impact on the optical properties of quantum dots.

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Artem Shikin, Elizaveta Lebedkina, Czcibor Ciostek, Pawel Holewa, Sokol Ndoni, Kristoffer Aldmal, Kresten Yvind, Marcin Syperek, Elizaveta Semenova. 2018-11-12. Synthesis and systematic optical investigation of selective area droplet epitaxy of InAs/InP quantum dots assisted by block copolymer lithography. https://arxiv.org/abs/1811.03927

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