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arXiv · 2312.14313

Lifetime Reduction of Single Germanium-Vacancy Centers in Diamond via a Tunable Open Microcavity

Rigel Zifkin·César Daniel Rodríguez Rosenblueth·Erika Janitz·Yannik Fontana·Lilian Childress
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Abstract

Coupling between a single quantum emitter and an optical cavity presents a key capability for future quantum networking applications. Here, we explore interactions between individual germanium-vacancy (GeV) defects in diamond and an open microcavity at cryogenic temperatures. Exploiting the tunability of our microcavity system to characterize and select emitters, we observe a Purcell-effect-induced lifetime reduction of up to $4.5\pm0.3$, and extract coherent coupling rates up to $360\pm20$ MHz. Our results indicate that the GeV defect has favorable optical properties for cavity coupling, with a quantum efficiency of at least $0.34\pm0.05$ and likely much higher.

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Rigel Zifkin, César Daniel Rodríguez Rosenblueth, Erika Janitz, Yannik Fontana, Lilian Childress. 2023-12-21. Lifetime Reduction of Single Germanium-Vacancy Centers in Diamond via a Tunable Open Microcavity. https://arxiv.org/abs/2312.14313

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