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arXiv · 2505.09267

High-Fidelity Control of a Strongly Coupled Electro-Nuclear Spin-Photon Interface

Abstract

Long distance quantum networking requires combining efficient spin-photon interfaces with long-lived local memories. Group-IV color centers in diamond (SiV, GeV, and SnV) are promising candidates for this application, containing an electronic spin-photon interface and dopant nuclear spin memory. Recent work has demonstrated state-of-the-art performance in spin-photon coupling and spin-spin entanglement. However, coupling between the electron and nuclear spins introduces a phase kickback during optical excitation that limits the utility of the nuclear memory. Here, we propose using the large hyperfine coupling of SnV-117 to operate the device at zero magnetic field in a regime where the memory is insensitive to optical excitation. We further demonstrate ground state spin control of a SnV-117 color center integrated in a photonic integrated circuit, showing 97.8% gate fidelity and 2.5 ms coherence time for the memory spin level. This shows the viability of the zero-field protocol for high fidelity operation, and lays the groundwork for building quantum network nodes with SnV-117 devices.

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BibTeXRIS

Isaac B. W. Harris, Ian Christen, Sofia M. Patomäki, Hamza Raniwala, Maxim Sirotin, Marco Colangelo, Kevin C. Chen, Carlos Errando-Herranz, David J. Starling, Ryan Murphy, Katia Shtyrkova, Owen Medeiros, Matthew E. Trusheim, Karl K. Berggren, P. Benjamin Dixon, Dirk Englund. 2025-05-14. High-Fidelity Control of a Strongly Coupled Electro-Nuclear Spin-Photon Interface. https://arxiv.org/abs/2505.09267

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