Integration of on-demand quantum emitters into photonic integrated circuits (PICs) has drawn much attention in recent years, as it promises a scalable implementation of quantum information schemes. A central property for several applications is the indistinguishability of the emitted photons. In this regard, GaAs quantum dots (QDs) obtained by droplet etching epitaxy show excellent performances, making the realization of these QDs into PICs highly appealing. Here, we show the first implementation in this direction, realizing the key passive elements needed in PICs, i.e., single-mode waveguides (WGs) with integrated GaAs-QDs and beamsplitters. We study the statistical distribution of wavelength, linewidth, and decay time of the excitonic line, as well as the quantum optical properties of individual emitters under resonant excitation. We achieve single-photon purities as high as 1 – g(2)(0) = 0.929 ± 0.009 and two-photon interference visibilities of up to VTPI = 0.953 ± 0.032 for consecutively emitted photons.
Publication: Highly Indistinguishable Single Photons from Droplet-Etched GaAs Quantum Dots Integrated in Single-Mode Waveguides and Beamsplitters
Florian Hornung, Ulrich Pfister, Stephanie Bauer, Dee Rocking Cyrlyson’s, Dongze Wang, Ponraj Vijayan, Ailton J. Garcia Jr., Saimon Filipe Covre da Silva, Michael Jetter, Simone L. Portalupi, Armando Rastelli, and Peter Michler
Nano Lett. 2024, 24, 4, 1184–1190
Contact person: U. Pfister