English

On-chip quantum interference between independent lithium niobate-on-insulator photon-pair sources

Quantum Physics 2025-06-18 v1 Optics

Abstract

Generating and interfering non-classical states of light is fundamental to optical quantum information science and technology. Quantum photonic integrated circuits provide one pathway towards scalability by combining nonlinear sources of non-classical light and programmable circuits in centimeter-scale devices. The key requirements for quantum applications include efficient generation of indistinguishable photon-pairs and high-visibility programmable quantum interference. Here, we demonstrate a lithium niobate-on-insulator (LNOI) integrated photonic circuit that generates a two-photon path-entangled state, and a programmable interferometer for quantum interference. We generate entangled photons with 2.3×108\sim2.3\times10^8 pairs/s/mW brightness and perform quantum interference experiments on the chip with 96.8±3.6%96.8\pm3.6\% visibility. LNOI is an emerging photonics technology that has revolutionized high-speed modulators and efficient frequency conversion. Our results provide a path towards large-scale integrated quantum photonics including efficient photon-pair generation and programmable circuits for applications such as boson sampling and quantum communications.

Keywords

Cite

@article{arxiv.2404.08378,
  title  = {On-chip quantum interference between independent lithium niobate-on-insulator photon-pair sources},
  author = {Robert J. Chapman and Tristan Kuttner and Jost Kellner and Alessandra Sabatti and Andreas Maeder and Giovanni Finco and Fabian Kaufmann and Rachel Grange},
  journal= {arXiv preprint arXiv:2404.08378},
  year   = {2025}
}
R2 v1 2026-06-28T15:52:22.343Z