Spin-photon entanglement of a single Er$^{3+}$ ion in the telecom band

Mehmet T. Uysal; Łukasz Dusanowski; Haitong Xu; Sebastian P. Horvath; Salim Ourari; Robert J. Cava; Nathalie P. de Leon; Jeff D. Thompson

arXiv · 2406.06515

Spin-photon entanglement of a single Er$^{3+}$ ion in the telecom band

Mehmet T. Uysal·Łukasz Dusanowski·Haitong Xu·Sebastian P. Horvath·Salim Ourari·Robert J. Cava·Nathalie P. de Leon·Jeff D. Thompson

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Abstract

Long-distance quantum communication using quantum repeaters is an enabling technology for secure communication, distributed quantum computing and quantum-enhanced sensing and metrology. As a building block of quantum repeaters, spin-photon entanglement has been demonstrated with both atomic and solid-state qubits. However, previously demonstrated qubits with long spin coherence do not directly emit photons into the low-loss telecom band that is needed for long-distance communication. Here, we demonstrate spin-photon entanglement using a single Er$^{3+}$ ion in a solid-state crystal, integrated into a silicon nanophotonic circuit. Direct emission into the telecom band enables an entanglement rate of 1.48 Hz over 15.6 km of optical fiber, with a fidelity of 73(3)$\%$. This opens the door to large-scale quantum networks based on scalable nanophotonic devices and many spectrally multiplexed Er$^{3+}$ ions.

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BibTeX RIS

Mehmet T. Uysal, Łukasz Dusanowski, Haitong Xu, Sebastian P. Horvath, Salim Ourari, Robert J. Cava, Nathalie P. de Leon, Jeff D. Thompson. 2024-06-10. Spin-photon entanglement of a single Er$^{3+}$ ion in the telecom band. https://arxiv.org/abs/2406.06515

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