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arXiv · 2604.11340

Optimal Two-Qubit Gates for Group-IV Color-Centers in Diamond

Jurek Frey·Katharina Senkalla·Philipp J. Vetter·Fedor Jelezko·Frank K. Wilhelm·Matthias M. Müller
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Abstract

Color centers associated with group-IV dopants in diamond with long-lived nuclear spins have emerged as major candidates for distributed quantum computing nodes and quantum repeaters. Several proof-of-principle experiments have already been demonstrated. A key operation for long-distance entanglement-distribution protocols are fast and robust gates between the electron spin and a nuclear spin. Here, we investigate numerically for an existing experimental platform of a Germanium-vacancy (GeV) center with a strongly-coupled ${}^{13}$C spin, how such gates can be implemented via quantum optimal control. In the presence of realistic noise we investigate different parameter regimes and gate operations and obtain robust two-qubit gates with fidelities exceeding $99.9 \%$. The framework provides a scalable strategy for group-IV quantum nodes and can be adapted to related architectures.

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Jurek Frey, Katharina Senkalla, Philipp J. Vetter, Fedor Jelezko, Frank K. Wilhelm, Matthias M. Müller. 2026-04-13. Optimal Two-Qubit Gates for Group-IV Color-Centers in Diamond. https://arxiv.org/abs/2604.11340

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