This study investigates the performance of droplet-etched GaAs quantum dots (QDs) integrated into micropillar structures using a deterministic fabrication technique. We demonstrate a unity QD positioning yield across 74 devices and consistent device performance. Under p-shell excitation, the QD decay dynamics within the micropillars exhibit biexponential behavior, accompanied by intensity fluctuations limiting the source efficiency to < 4.5%. Charge stabilization via low-power above-band LED excitation effectively reduces these fluctuations, doubling the source efficiency to ∼ 9%. Moreover, we introduce suppression of radiation modes by introducing cylindrical rings theoretically predicted to boost the collection efficiency by a factor of 4. Experimentally, only a modest improvement is obtained, underscoring the influence of even minor fabrication imperfections for this advanced design. Our findings demonstrate the reliability of our deterministic fabrication approach in producing high-yield, uniform devices, while offering detailed insights into the influence of charge noise and complex relaxation dynamics on the performance.
@article{arxiv.2502.09367,
title = {Deterministic fabrication of GaAs-quantum-dot micropillar single-photon sources},
author = {Abdulmalik A. Madigawa and Martin Arentoft Jacobsen and Claudia Piccinini and Paweł Wyborski and Ailton Garcia and Saimon F. Covre da Silva and Armando Rastelli and Battulga Munkhbat and Niels Gregersen},
journal= {arXiv preprint arXiv:2502.09367},
year = {2025}
}