The germanium vacancy in diamond (GeV) is a promising candidate for color center based quantum networking. Yet, like for other group-IV vacancy defects in diamond, achieving fast, high-fidelity qubit operations using traditional magnetic resonance techniques is experimentally challenging due to a weak magnetic dipole and susceptibility to thermally induced decoherence. Here, we perform all-optical control of the GeV and realize Rabi frequencies exceeding ∼20~MHz. We do so by driving the two Λ-systems of the GeV simultaneously and apply this to probe the spin coherence (T2∗=224±14~ns, T2H=11.9±0.3~μs). Our control scheme is applicable to other color centers and particularly, other group-IV defects for which, the scheme may be optimized to improve all-optical control in these systems.
@article{arxiv.2402.00244,
title = {Coherent all-optical control of the germanium vacancy in diamond},
author = {C. Adambukulam and J. A. Scott and S. Q. Lim and I. Aharonovich and A. Morello and A. Laucht},
journal= {arXiv preprint arXiv:2402.00244},
year = {2025}
}