Fluorescent nanodiamonds (NDs) are hard, nontoxic, have high melting point and possess physical and chemical stability. In this paper, the NDs with nitrogen vacancy (NV) centres have been studied with steady-state and time-resolved photoluminescence spectroscopy. The broad fluorescence spectrum spans in the visible-near IR region (from 500 nm to 900 nm) with presence of prominent characteristic peaks of neutral and negatively charged NVs. The fluorescence decay of bulk NV centres shows multi-exponential decay with different lifetimes at two excitation wavelengths. When brought in contact with the polystyrene microspheres, the NV centres exhibit whispering gallery modes (WGMs) built upon the background spectrum. The fluorescence decay of NV centres in presence of the microcavity gives evidence of inhibition of the decay rate. Simulations from the finite element method show evanescent field coupling. The results have been explained in terms of the Purcell's effect as well as the slow light that results due to the interference of the ballistic and circulating lights in the microcavity.

荧光纳米金刚石（NDs）坚硬，无毒，熔点高且具有物理和化学稳定性。本文利用稳态和时间分辨光致发光光谱技术研究了具有氮空位（NV）中心的ND。宽的荧光光谱跨在可见光附近的IR区域（从500 nm到900 nm），具有中性和带负电荷的NV的突出特征峰。整体NV中心的荧光衰减显示在两个激发波长下具有不同寿命的多指数衰减。当与聚苯乙烯微球接触时，NV中心会显示基于背景光谱的回音壁模式（WGM）。在微腔存在下，NV中心的荧光衰减提供了抑制衰减速率的证据。有限元方法的仿真显示了van逝场耦合。已经根据珀塞尔效应以及由于微腔中的弹道光和循环光的干涉而导致的慢速光来解释了结果。