Hybrid integration of InAs/GaAs quantum dot (QD) single-photon sources (SPSs) is a promising approach for introducing quantum light into SiN photonic integrated circuits. However, the large refractive-index mismatch between GaAs and SiN poses a challenge for efficient optical coupling. Here, we propose and experimentally demonstrate hybrid integration of an InAs/GaAs QD-SPS on SiN using a coupled crossover waveguide structure. A photonic crystal nanocavity is employed for coupling QD emission into a GaAs waveguide, which efficiently transfers photons to a SiN waveguide at the crossover section. We observed Purcell-enhanced single-photon emission, on-chip propagation, and outcoupling through a SiN grating coupler.
@article{arxiv.2602.05491,
title = {Quantum dot single photon source on SiN integrated with coupled crossover waveguides},
author = {Akinari Fujita and Hironobu Yoshimi and Natthajuks Pholsen and Masahiro Kakuda and Makoto Okano and Satoshi Iwamoto and Yasuhiko Arakawa and Yasutomo Ota},
journal= {arXiv preprint arXiv:2602.05491},
year = {2026}
}