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arXiv · 2507.06553

Tunable cavity coupling of a single SnV$^{-}$ center in nanodiamond across bad-emitter and bad-cavity regimes

Selene Sachero·Robert Berghaus·Elena Nieto Hernandez·Florian Feuchtmayr·Niklas Lettner·Patrick Maier·Sviatoslav Ditalia Tchernij·Alexander Kubanek
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Abstract

Efficient coupling between quantum emitters and optical cavities is essential for scalable quantum photonic technologies. Group IV vacancy centers in diamond, particularly the negatively charged tin-vacancy center, have emerged as promising candidates due to their spectral stability, high Debye-Waller factor and large orbital splitting in ground-states. Here, we demonstrate controlled couplinag of a single negatively charged tin vacancy center hosted in a nanodiamond to a fully tunable Fabry-Perot microcavity. At cryogenic temperatures, we access the weak coupling regime and observe a transition from the bad-emitter to the bad-cavity regime as the optical transition of the color center narrows. At 4 K, a Purcell factor exceeding 1.7 is measured, confirming cavity-enhanced emission. The obtained results demonstrate the potential of SnV$^{-}$ centers in nanodiamonds as a coherent single-photon source for quantum networks.

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Selene Sachero, Robert Berghaus, Elena Nieto Hernandez, Florian Feuchtmayr, Niklas Lettner, Patrick Maier, Sviatoslav Ditalia Tchernij, Alexander Kubanek. 2025-07-09. Tunable cavity coupling of a single SnV$^{-}$ center in nanodiamond across bad-emitter and bad-cavity regimes. https://arxiv.org/abs/2507.06553

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