Berlin 2024 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

HL: Fachverband Halbleiterphysik

HL 13: Poster I

HL 13.5: Poster

Monday, March 18, 2024, 15:00–18:00, Poster E

High-reflectivity Al₂O₃/Al_0.3Ga_0.7As distributed Bragg reflectors and microcavities for photon Bose-Einstein-condensates in GaAs quantum wells — •Lara Schmieder^1,3, Nils von den Driesch^2,3, Yurii Kutovyi^1,3, Siqi Qiao^1,3, Christoph Krause², Benjamin Bennemann², and Alexander Pawlis^1,2,3 — ¹PGI-9, Forschungszentrum Jülich GmbH — ²PGI-10, Forschungszentrum Jülich GmbH — ³JARA-FIT, Jülich Aachen Research Alliance

Significant present research is focused on the realization of Photon-Bose-Einstein-Condensates (P-BECs) for applications in quantum technology. We propose a scalable chip-architectur composed of III-V semiconductor microcavities with GaAs quantum wells. The latter are directly grown between high-reflectivity AlOx based Distributed Bragg Reflectors (DBRs) to form a high-finesse microcavity. In order to reach the thermalization conditions of a semiconductor based P-BEC, extremely high reflectivity of the DBRs is required.

We meet these condition by establishing AlOx based DBRs fabricated via a combined nanostructuring and wet-oxidation process of as-grown AlAs/Al_0.3Ga_0.7As superlattices. Reflectivity measurements of our AlOx based Bragg reflectors owe much higher reflectivity as standard AlAs/Al_0.3Ga_0.7As Bragg-mirrors with similar number of periods. Quantitative analysis of microcavities with AlOx based DBRs confirm that 8-fold stacks are already sufficient to achieve high enough finesse to overcome the above mentioned thermalization limit.

Keywords: Distributed Bragg Reflector; Microcavity; Wet-oxidation