Postdoctoral Fellowship: MPS-Ascend: Controlling the spin and charge of color centers in diamond under cryogenic conditions

非技术描述钻石是一种仅由碳制成的非凡材料。钻石是最坚硬的天然材料之一，与许多电绝缘体不同的是，它是良好的导热体。这些特性导致了许多工业应用，例如用于研磨、钻孔和切割的磨料。钻石还拥有一个敏感的磁场和电场探测器：氮空位(NV)中心。NV中心可以用来感测磁性物体，并有可能用作量子计算的量子比特(Qubit)。大多数关于钻石中NV中心的工作都是在常温和环境条件下完成的。低温条件极大地改变了它的光学性质，为控制和读出NV中心创造了新的机会。在这个MPS-Ascend项目中，PI将使用他在博士工作期间开发的仪器来研究NV自旋、光学和电子性质在低温下的相互作用。PI将把他的研究与以PI作为教育工作者的经验为基础的教育活动结合起来，包括对本科生和初级研究生的指导以及在当地高中的外展活动。技术说明由于局部菌株对NV光谱的影响而产生的并发症，NV中心的低温操作在传感方面受到的关注相对较少。PI计划进行一项系统的研究，以揭示晶体应变和旋光性之间的相互作用。这些研究将由PI开发的具有多色激发能力的低温显微镜实现。该仪器集成了磁共振和原子力显微镜功能，可以结合起来实施NV扫描探头实验。活动将集中在NV在低温条件下显示的窄的、自旋选择性的光学跃迁，有两个主要目标：(I)开发NV自旋读出的增强形式，重点是在传感方面的应用，以及(Ii)研究共振光激发下的NV电荷状态动力学，着眼于次衍射光学存储器。计划中的研究还将使有效的自旋到电荷转换方案成为获得增强的NV敏感性的替代方案。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Non-technical DescriptionDiamond is a remarkable material made only of carbon. Diamond is one of the hardest natural materials and, unlike many electrical insulators, it is a good conductor of heat. These properties have led to many industrial applications, such as an abrasive used in grinding, drilling, and cutting. Diamond also hosts a sensitive detector of magnetic and electric fields: the nitrogen vacancy (NV) center. NV centers can be used to sense magnetic objects and have potential for use as quantum bits (qubits) for quantum computing. Most work on NV centers in diamond has been done at room temperature under ambient conditions. Cryogenic conditions substantially alter its optical properties, creating new opportunities for control and readout of NV centers. In this MPS-Ascend project, the PI will use instrumentation developed during his doctoral work to investigate the interplay between the NV spin, optical, and electronic properties at low temperatures. The PI will integrate his research with educational activities that build on the PI’s experience as an educator, including mentorships of undergraduates and junior graduates as well as outreach activities in local high schools.Technical DescriptionCryogenic manipulation of NV centers has received relatively little attention in the context of sensing, due to complications deriving from the impact of local strain on the NV optical spectrum. The PI plans to carry out a systematic investigation that will shed light on the interplay between crystal strain and optical cyclicity. These studies will be enabled by a cryogenic microscope developed by the PI that has multi-color excitation capabilities. This instrumentation integrates magnetic resonance and atomic force microscopy capabilities that can be combined to implement NV scanning probe experiments. Activities will center on the narrow, spin-selective optical transitions NVs display in the cryogenic regime with two main goals: (i) develop enhanced forms of NV spin readout with emphasis on applications to sensing, and (ii) study the NV charge state dynamics under resonant optical excitation with an eye on sub-diffraction optical memories. The planned studies will also enable effective spin-to-charge conversion schemes as an alternative to attaining enhanced NV sensitivity.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.