First-principles analyses are performed on the diamond europium vacancy (EuV) color center. Three different models indicate that the structure of the EuV color center contains a stable vacancy around the Eu atom. Energy band calculations show that the stable EuV color center has spin polarization and its spin-up energy level structure is highly suitable as a single-photon source. The zero-point transition energy is 1.989 eV (623 nm). The existence of metastable energy levels in the EuV is also predicted. Nitrogen atoms have a negative impact on the electronic structure of the EuV, in comparison to diamond color centers such as NE8 and TiV-N.

中文翻译：

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钻石中铕空位色心的原理研究

对钻石铕空位 (EuV) 色心进行第一性原理分析。三种不同的模型表明 EuV 色心的结构在 Eu 原子周围包含一个稳定的空位。能带计算表明，稳定的 EuV 色心具有自旋极化，其自旋能级结构非常适合作为单光子源。零点跃迁能量为 1.989 eV (623 nm)。还预测了 EuV 中亚稳态能级的存在。与 NE8 和 TiV-N 等钻石色心相比，氮原子对 EuV 的电子结构有负面影响。