光纤集成的碳化硅色心量子精密测量研究

In recent years, color centers in silicon carbide (SiC) have attracted increasing attention owing to their excellent optical properties and long spin coherence time. As compared with NV centers in diamond, color centers in silicon carbide have three advantages. Firstly, SiC is a technologically mature semi-conductor material, which have widely used in microelectronics systems and high-power electronics, etc. Secondly, fluorescence wave-length of the color centers in SiC is in the near-infrared, and infrared spectral region, which is more suitable for integrating with fiber. Thirdly, the coherence time of the color centers in SiC is larger than NV center in diamond. In recent years, it has been explored in quantum metrologies such as magnetic field sensing, electric field sensing, thermal sensing, and force sensing. However, the application of such kind of quantum sensing is severely limited owing to the inconvenience in using the bulk SiC and operation in macroscopic laboratory optical setups. In order to improve the spatial resolution and integrate the SiC color center quantum sensor, in this project, we propose to study the fiber-integrated SiC-based quantum metrology. First, we integrate the nano-SiC and micro-SiC with the fiber with high efficiency. Then we use the fiber-integrated SiC color center to detect the magnetic and temperature with high-spatial-resolution and high sensitivity. The implementation of this project will pave the way for the integration and application of the SiC-based quantum sensing devices.

近些年来，碳化硅色心由于其优异的光学性质和自旋性质，吸引了人们越来越多的关注。相比于金刚石NV色心，碳化硅色心具有以下优点：一、碳化硅是一种广泛应用的半导体材料，有成熟的生长和微纳加工艺。二、碳化硅色心波长处在近红外波段，更有利于和光纤集成。三、理论和实验证明碳化硅色心的相干时间比金刚石NV色心长。目前碳化硅色心已经在量子精密测量：磁场，电场，温度，应力等方面有一些应用。但是之前量子精密测量实验用的都是块状样品，而且都是在实验室环境，为了进一步提高空间分辨率，实现集成化和实用化，本项目将开展光纤集成的碳化硅的量子精密测量研究。通过纳米和微米碳化硅与光纤高效耦合，实现磁场和温度的高空间、高灵敏分辨率的探测。本项目的实施将进一步推进基于碳化硅色心的量子精密测量的集成化、实用化。

近些年来，碳化硅色心由于其优异的光学性质和自旋性质，吸引了人们越来越多的关注。目前碳化硅色心已经在量子精密测量：磁场，电场，温度，应力等方面有一些应用。但是之前量子精密测量实验用的都是块状样品，而且都是在实验室环境，为了进一步提高空间分辨率，实现集成化和实用化，本项目将开展光纤集成的碳化硅的量子精密测量研究。通过纳米和微米碳化硅与光纤高效耦合，实现磁场和温度的高空间、高灵敏分辨率的探测，将进一步推进基于碳化硅色心的量子精密测量的集成化、实用化。本项目按计划进行了大量实验研究，完成了绝大部分的计划内容。1. 本项目实现了光纤集成碳化硅硅空位色心磁力计。磁场探测灵敏度为12.3 μT/Hz1/2。2.实现了光纤集成碳化硅双空位色心磁力计和温度计。磁场探测灵敏度为3.9 μT/Hz1/2，温度探测灵敏度为163.2 mK/Hz1/2。除此之外，我们还执行了部分计划外的工作。3. 实现了碳化硅硅空位色心的反斯托克斯激发的自旋相干操控。4. 实现了PL6单个双空位色心的室温高对比度自旋相干操控。5. 研究了碳化硅NV色心室温光学性质，证明其是偏振度达到90%的三能级结构的单色心。6. 优化了碳化硅双空位色心的ODMR谱，使得其磁场探测灵敏度提高10倍。7. 实现了双空位色心共振激发下的光电荷态调控。8.实现了碳化硅双空位色心的高压传感和高压磁探测。9. 实现了腔增强的纳米金刚石和单层石墨烯的共振能量转移。