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arXiv · 2508.14566

Electrically pumped ultrabright entangled photons on chip

Xu-Feng Jiao·Ming-Yang Zheng·Yi-Hang Chen·Bo Cao·Xina Wang·Yang Liu·Cheng-Ao Yang·Xiu-Ping Xie·Chao-Yang Lu·Zhi-Chuan Niu·Qiang Zhang·Jian-Wei Pan
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Abstract

Entangled photon sources (EPS) are essential for quantum science and technology. Despite advancements in integrated optical platforms like thin-film lithium niobate, a scalable, high-performance, chip-scale EPS has remained elusive. We address this by demonstrating an electrically pumped, post-selection-free polarization-EPS, achieved through hybrid integration of a distributed feedback laser with thin-film lithium niobate chip which integrates periodically poled lithium niobate waveguides, beam splitter, and polarization rotator combiner. By injecting current into the chip, we realize a high-performance EPS with a bandwidth of 73 nm and an entanglement pair generation rate of 4.5*10^10 pairs/s/mW. The polarization entanglement shows Bell-state fidelities above 96% across frequency-correlated modes. This compact, integrated EPS enables key applications, including high-speed quantum key distribution via wavelength division multiplexing, satellite-based quantum communication, and entanglement-based quantum metrology.

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Xu-Feng Jiao, Ming-Yang Zheng, Yi-Hang Chen, Bo Cao, Xina Wang, Yang Liu, Cheng-Ao Yang, Xiu-Ping Xie, Chao-Yang Lu, Zhi-Chuan Niu, Qiang Zhang, Jian-Wei Pan. 2025-08-20. Electrically pumped ultrabright entangled photons on chip. https://arxiv.org/abs/2508.14566

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