标题： 设计超小纳米金刚石中可光学寻址的氮空位中心：第一性原理计算的见解 显示英文标题

标题： Designing Optically Addressable Nitrogen-Vacancy Centers in Ultra-Small Nanodiamonds: Insights from First-Principles Calculations

摘要： 超小纳米金刚石（USNDs）是荧光和量子传感应用的有前途的平台。 在这里，我们进行了关于USND中色心的第一性原理电子结构计算，特别是氮空位（NV-），并研究了它们的光学可寻址性作为表面终止的函数。 我们考虑了孤立的纳米颗粒和不同包装程度的USND阵列，并在分析中包括了量子振动效应，使用随机方法。 我们发现，如果纳米颗粒被氟、羟基和醚终止，USND中的NV可以稳定在负电荷状态。 虽然氟终止可用于荧光生物标记，但我们建议羟基和醚终止有利于量子传感应用。 我们还发现，当粒子间距离大于纳米颗粒的直径时，NV-可以在USND阵列中稳定。 有趣的是，在阵列中发现的单粒子能级的声子重正化有助于带负电的NV中心的电荷稳定性。 显示英文摘要

摘要： Ultrasmall nanodiamonds (USNDs) are promising platforms for fluorescent and quantum sensing applications. Here we present first-principles electronic structure calculations of color centers in USNDs, specifically the nitrogen-vacancy (NV-) and we investigate their optical addressability as a function of the surface termination. We consider both isolated nanoparticles and arrays of USNDs with different degrees of packing, and we include quantum vibronic effects in our analysis, using stochastic methods. We find that the NV in USNDs can be stabilized in a negative charge state if the nanoparticles are terminated by fluorine, hydroxyl, and ether. While fluorine terminations can be used for fluorescent bio-tags, we suggest that hydroxyl and ether terminations are beneficial for quantum sensing applications. We also find that the NV- can be stabilized in arrays of USNDs when inter-particle separations are larger than the diameter of the nanoparticle. Interestingly, the phonon renormalizations of single-particle energy levels found in arrays contribute to the charge stability of negatively charged NV centers.