The nitrogen-vacancy center in diamond has been explored extensively as a light-matter interface for quantum information applications, however it is limited by low coherent photon emission and spectral instability. Here, we present a promising interface based on an alternate defect with superior optical properties (the germanium-vacancy) coupled to a finesse $11,000$ fiber cavity, resulting in a ${31}_{-15}^{+12}$,-fold increase in the spectral density of zero phonon line emission. This work sets the stage for cryogenic experiments, where we predict a measurable increase in the spontaneous emission rate.

中文翻译：

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金刚石膜中单个锗空位中心的腔增强光子发射

金刚石中的氮空位中心已被广泛地用作量子信息应用中的光-物质界面，但受到低相干光子发射和光谱不稳定性的限制。在这里，我们提出了一个有前途的界面，该界面基于具有优良光学特性（锗空位）的替代缺陷以及精细的光学性能。$11，000$ 纤维腔，导致 ${31}_{-15}^{+12}$零声子线发射的光谱密度增加1倍。这项工作为低温实验奠定了基础，我们在低温实验中预测了自发发射率的可测量提高。