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arXiv · 2305.18923

A diamond nanophotonic interface with an optically accessible deterministic electronuclear spin register

Ryan A. Parker·Jesús Arjona Martínez·Kevin C. Chen·Alexander M. Stramma·Isaac B. Harris·Cathryn P. Michaels·Matthew E. Trusheim·Martin Hayhurst Appel·Carola M. Purser·William G. Roth·Dirk Englund·Mete Atatüre
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Abstract

A contemporary challenge for the scalability of quantum networks is developing quantum nodes with simultaneous high photonic efficiency and long-lived qubits. Here, we present a fibre-packaged nanophotonic diamond waveguide hosting a tin-vacancy centre with a spin-1/2 $^{117}$Sn nucleus. The interaction between the electronic and nuclear spins results in a signature 452(7) MHz hyperfine splitting. This exceeds the natural optical linewidth by a factor of 16, enabling direct optical nuclear-spin initialisation with 98.6(3)% fidelity and single-shot readout with 80(1)% fidelity. The waveguide-to-fibre extraction efficiency of our device of 57(6)% enables the practical detection of 5-photon events. Combining the photonic performance with the optically initialised nuclear spin, we demonstrate a spin-gated single-photon nonlinearity with 11(1)% contrast in the absence of an external magnetic field. These capabilities position our nanophotonic interface as a versatile quantum node in the pursuit of scalable quantum networks.

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Ryan A. Parker, Jesús Arjona Martínez, Kevin C. Chen, Alexander M. Stramma, Isaac B. Harris, Cathryn P. Michaels, Matthew E. Trusheim, Martin Hayhurst Appel, Carola M. Purser, William G. Roth, Dirk Englund, Mete Atatüre. 2023-05-30. A diamond nanophotonic interface with an optically accessible deterministic electronuclear spin register. https://arxiv.org/abs/2305.18923

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