• Advanced Photonics
  • Vol. , Issue , ()
You Xiang, Zheng Ming, Chen Si, Liu Run, Qin Jian, Xu Mo, Ge Zheng, Chung T, Qiao Yu, Jiang Yang, Zhong Han, Chen Ming, Wang Hui, He Yu, Xie Xiu, Li Hao, You Lixing, Schneider Christian, Yin Juan, Chen tengyun, Benyoucef Mohamed, Huo Yongheng, Hofling Sven, Zhang Qiang, Lu Chaoyang , Pan Jianwei
Author Affiliations
  • University of Science and Technology of China
  • Jinan Institute of Quantum Technology
  • Shanghai Institute of Microsystem and Information Technology
  • Chinese Acad Sci
  • University of Oldenburg
  • University of Kassel
  • Universitat Wurzburg
  • show less

    Abstract

    In the quest to realize a scalable quantum network, semiconductor quantum dots (QDs) offer distinct advantages including high single-photon efficiency and indistinguishability, high repetition rate (tens of GHz with Purcell enhancement), interconnectivity with spin qubits, and a scalable on-chip platform. However, in the past two decades, the visibility of quantum interference between independent QDs rarely went beyond the classical limit of 50\% and the distances were limited from a few meters to kilometers. Here, we report quantum interference between two single photons from independent QDs separated by 302 km optical fiber. The single photons are generated from resonantly driven single QDs deterministically coupled to microcavities. Quantum frequency conversions are used to eliminate the QD inhomogeneity and shift the emission wavelength to the telecommunication band. The observed interference visibility is 0.67$\pm$0.02 (0.93$\pm$0.04) without (with) temporal filtering. Feasible improvements can further extend the distance to $\sim$600 km. Our work represents a key step to long-distance solid-state quantum networks.
    Manuscript Accepted: Nov. 24, 2022
    Posted: Nov. 24, 2022
    DOI: AP