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 13C 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.
@article{arxiv.2604.11340,
title = {Optimal Two-Qubit Gates for Group-IV Color-Centers in Diamond},
author = {Jurek Frey and Katharina Senkalla and Philipp J. Vetter and Fedor Jelezko and Frank K. Wilhelm and Matthias M. Müller},
journal= {arXiv preprint arXiv:2604.11340},
year = {2026}
}