Regensburg 2022 – scientific programme

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

HL: Fachverband Halbleiterphysik

HL 17: Quantum Dots and Wires 4: Devices

HL 17.2: Talk

Wednesday, September 7, 2022, 09:45–10:00, H32

Realization of Gaussian-shaped micro-cavities for Quantum Dots emitting in the telecom C-band — •Jens Jakschik — Institut für Halbleiteroptik und funktionelle Grenzflächen, Center for Integrated Quantum Science and Technology (IQST) and SCoPE, University of Stuttgart, Germany

Semiconductor quantum dots (QDs) are a prime candidate for the generation of efficient single, indistinguishable photons. When utilizing these QDs for e.g. long-distance quantum communication, it is important to operate at the transmission loss minimum of the existing global optical fiber network. Therefore, the QDs have to emit in the telecom C-Band (~1550 nm). To keep the advantages of the mature GaAs technology, the QDs are grown on an InGaAs metamorphic buffer (MMB) layer with high In-content on GaAs. The emission of QDs can be optimized by confining them into cavities. In this work novel Gaussian-shaped micro-cavities based on high-reflective DBRs are used. To reach high quality factors and increase the extraction efficiency in Gaussian-shaped cavities, the radial symmetry given by the wet-chemically etched Gaussian-shaped microlens, forming the center of the cavity has to be preserved over multiple layers of top DBR growth. This has to be realized despite the varying growth rates of InGaAs along different crystal axes. In this contribution, we present the results of the optical simulations for optimizing these cavities for the telecom C-Band, as well as the effect of different growth conditions on the overgrowth of InGaAs on wet-chemically pre-structured substrates to enable the fabrication of novel Gaussian-shaped micro-cavities.