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arXiv · 2510.09164

High-Fidelity Single-Shot Readout and Selective Nuclear Spin Control for a Spin-1/2 Quantum Register in Diamond

Prithvi Gundlapalli·Philipp J. Vetter·Genko Genov·Michael Olney-Fraser·Peng Wang·Matthias M. Müller·Katharina Senkalla·Fedor Jelezko
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Abstract

Quantum networks offer a way to overcome the size and complexity limitations of single quantum devices by linking multiple nodes into a scalable architecture. Group-IV color centers in diamond, paired with long-lived nuclear spins, have emerged as promising building blocks demonstrating proof-of-concept experiments such as blind quantum computing and quantum-enhanced sensing. However, realizing a large-scale electro-nuclear register remains a major challenge. Here we establish the germanium-vacancy (GeV) center as a viable platform for such network nodes. Using correlation spectroscopy, we identify single nuclear spins within a convoluted spin environment, overcoming limitations imposed by the color center's spin-$1/2$ nature and thereby enabling indirect control of these nuclear spins. We further demonstrate high-fidelity single-shot readout of both the GeV center ($95.8\,\%$) and a neighboring ${}^{13}\text{C}$ nuclear spin ($93.7\,\%$), a key tool for feed-forward error correction. These critical advances position the GeV center as a compelling candidate for next-generation quantum network nodes.

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Prithvi Gundlapalli, Philipp J. Vetter, Genko Genov, Michael Olney-Fraser, Peng Wang, Matthias M. Müller, Katharina Senkalla, Fedor Jelezko. 2025-10-10. High-Fidelity Single-Shot Readout and Selective Nuclear Spin Control for a Spin-1/2 Quantum Register in Diamond. https://arxiv.org/abs/2510.09164

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