Scalable Deterministic Integration of Two Quantum Dots into an On-Chip Quantum Circuit
Shulun Li, Yuhui Yang, Johannes Schall, Martin von Helversen, Chirag C. Palekar, Hanqing Liu, Léo J. Roche, Sven Rodt, Haiqiao Ni, Yu Zhang, Zhichuan Niu, Stephan Reitzenstein
Abstract
Integrated quantum photonic circuits (IQPCs) with deterministically integrated quantum emitters are critical elements for scalable quantum information applications and have attracted significant attention in recent years. However, scaling them up toward fully functional photonic circuits with multiple deterministically integrated quantum emitters to generate photonic input states remains a great challenge. In this work, we report on a monolithic prototype IQPC consisting of two preselected quantum dots deterministically integrated into nanobeam cavities at the input ports of a 2 × 2 multimode interference beam splitter. The on-chip beam splitter exhibits a splitting ratio of nearly 50/50 and the integrated quantum emitters have high single-photon purity, enabling on-chip Hanbury Brown and Twiss (HBT) experiments, depicting deterministic scalability. Overall, this marks a cornerstone toward scalable and fully functional IQPCs.