Colour centres in hexagonal boron nitride as memory assisted single photon sources

六方氮化硼(HBN)是一种宽禁带的二维材料，可以容纳多个色心作为单光子源。值得注意的是，即使在室温和更高的温度下，单个缺陷的发射线宽度也是窄的。在过去的两年里，已经报道了终身有限线宽的潜力。这为构建室温相干量子光源提供了诱人的前景，而不是非相干单光子光源。一个经典的类比是从灯泡到激光的过渡。此外，最近有许多关于hBN中系综在室温下的微秒尺度自旋相干时间的报道，这为潜在的纠错提供了存储资源。主要挑战是在单个缺陷水平上实现光学和自旋相干。该项目将研究hBN中单个缺陷的光学相干性质，与最近在探测自旋相干性的光学检测磁共振实验中的成功相结合，将更好地建立这种材料系统在量子光子学中的应用潜力。该项目将把自旋缺陷纳入可调谐的微腔中，以增强发射，并最终实现难以区分的光子。

Hexagonal boron nitride (hBN), a wide bandgap, two-dimensional material can host a number of colour centers that act as single photon sources. Remarkably, the emission linewidth for single defects is narrow bandwidth, even at room temperature and beyond. In the last two years, the potential for lifetime limited linewidths has been reported. This offers the tantalizing prospect of building room temperature coherent quantum light sources, versus incoherent single photon sources. A classical analogy would be a transition from light bulb to laser. Furthermore, there are a number of recent reports of microsecond scale spin coherence times for ensembles in hBN at room temperature, providing a memory resource for potential error correction.The main challenge is achieving optical and spin coherence on the single defect level. This project will study the optical coherence properties of single defects in hBN, which when combined with recent successes in optically detected magnetic resonance experiments probing the spin coherence, will better establish the potential of this material system for applications to quantum photonics. The project will incorporate the spin defects into tuneable microcavities to enhance emission and ultimately achieving indistinguishable photons.