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arXiv · 2402.00244

Coherent all-optical control of the germanium vacancy in diamond

C. Adambukulam·J. A. Scott·S. Q. Lim·I. Aharonovich·A. Morello·A. Laucht
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Abstract

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 $\sim 20$~MHz. We do so by driving the two $\Lambda$-systems of the GeV simultaneously and apply this to probe the spin coherence ($T_2^*=224\pm14$~ns, $T_2^{\rm H}=11.9\pm0.3$~$\mu$s). 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.

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C. Adambukulam, J. A. Scott, S. Q. Lim, I. Aharonovich, A. Morello, A. Laucht. 2024-01-31. Coherent all-optical control of the germanium vacancy in diamond. https://arxiv.org/abs/2402.00244

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