Scalable on-chip integration of diamond color centers for cryogenic quantum photonics

Quantum Physics [Submitted on 8 Apr 2026] Scalable on-chip integration of diamond color centers for cryogenic quantum photonics H. Kurokawa, K. Sato, M. Kamata, S. Ishida, H. Matsukiyo, N. Pholsen, M. Nishioka, S. Ji, H. Otsuki, S. Hachuda, M. Kunii, T. Tamanuki, K. Kimura, K. Takenaka, Y. Sekiguchi, S. Onoda, S. Iwamoto, T. Baba, H. Kosaka Chip integration of quantum emitters is a crucial milestone for scalable quantum photonic information processing. Among optically active defect centers for quantum photonics, diamond color centers are promising because of their long spin coherence times and high photon emission rates. However, for a coherent-photon emission, they typically require a cryogenic environment to protect optical coherence from thermal phonons, which makes chip integration challenging. In this paper, we develop a chip-integrated diamond photonic crystal cavity embedding an ensemble of nitrogen-vacancy (NV) centers. We confirm cryogenic operation by observing Purcell enhancement of NV-center emission via an edge-coupled optical fiber. This result demonstrates successful integration of diamond color centers, a photonic crystal cavity, and an optical waveguide-fiber package, representing a key step toward scalable diamond-based quantum communication platforms. Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2604.06984 [quant-ph]   (or arXiv:2604.06984v1 [quant-ph] for this version)   https://doi.org/10.48550/arXiv.2604.06984 Focus to learn more Submission history From: Hodaka Kurokawa [view email] [v1] Wed, 8 Apr 2026 12:00:36 UTC (3,735 KB) Access Paper: HTML (experimental) view license Current browse context: quant-ph < prev   |   next > new | recent | 2026-04 References & Citations INSPIRE HEP NASA ADS Google Scholar Semantic Scholar Export BibTeX Citation Bookmark Bibliographic Tools Bibliographic and Citation Tools Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) Connected Papers Toggle Connected Papers (What is Connected Papers?) Litmaps Toggle Litmaps (What is Litmaps?) scite.ai Toggle scite Smart Citations (What are Smart Citations?) Code, Data, Media Demos Related Papers About arXivLabs Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)