Ambal Kapildeb, McMichael Robert D
National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
Rev Sci Instrum. 2019 Feb;90(2):023907. doi: 10.1063/1.5065515.
We describe a real-time method to obtain normalized differential count rate signals from modulated systems with photon detection at single-photon count rates. The method is demonstrated with a real-time peak-locking and frequency control to track magnetic field using optically detected magnetic resonance of nitrogen-vacancy centers in diamond. This procedure allows us to measure the magnetic field continuously with a sensitivity of 4.1 µT/Hz and to track magnetic field sweep rates up to 50 µT/s. The differential rate meter automates the processing of voltage pulse outputs from the photon detector and provides noise levels on par with traditional photon counting methods using digital counters.
我们描述了一种实时方法，用于从具有单光子计数率光子检测的调制系统中获取归一化差分计数率信号。该方法通过实时峰值锁定和频率控制进行了演示，以利用金刚石中氮空位中心的光探测磁共振来跟踪磁场。此过程使我们能够以4.1 µT/Hz的灵敏度连续测量磁场，并跟踪高达50 µT/s的磁场扫描速率。差分速率计可自动处理光子探测器的电压脉冲输出，并提供与使用数字计数器的传统光子计数方法相当的噪声水平。
