基于光纤耦合金刚石NV色心系综磁强计的电路诊断方法

为考查应用新型磁强计——金刚石氮空穴（nitrogen-vacancy, NV）色心系综磁强计进行电路诊断的可行性和可靠性，从金刚石NV色心系综磁强计的基本原理出发，搭建了一套光纤耦合金刚石NV色心系综磁强计测试实验系统，将探头紧贴于电路导线外壳，通过测量磁强计处磁场信号的变化实现对电路的诊断。实验结果表明，金刚石NV色心系综磁强计对电路异常引起的磁场变化响应明显，对电流的分辨率优于50 mA；当探头和导线距离发生变化时，观测信号曲线呈现明显的台阶，空间分辨率优于0.4 mm。本系统采用更加简洁的方案实现了10 μT量级磁场分辨率的性能指标，能够诊断出电路的电流变化并进行精确定位，可广泛应用电路无损检测及可靠性评估。

The circuit diagnosis method with diamond NV center ensemble magnetometer based on fiber coupling

To investigate the feasibility and the reliability of the new type magnetometer, namely, the diamond NV center ensemble magnetometer, in the non-destructive diagnose of the circuit abnormalities, an experimental system of the optical fiber coupled diamond NV center ensemble magnetometer is established based on the basic principles of the new type magnetometer. In this system, the probe is sticked close to the shell of the wire, and the diagnosis of the circuit is realized by measuring the change of the magnetic field signal from the magnetometer. The results reveal that the diamond NV center ensemble magnetometer responds sensitively to the change of the magnetic field caused by the circuit abnormalities. The current resolution of the magnetometer is better than 50 mA. An obvious step-shaped signal can be observed when the distance between the probe and the wire changes, and the spatial resolution is better than 0.4 mm. In the system, a very concise scheme is adopted to realize a magnetic field resolution of 10 μT level. Experiments show that the system can diagnose the current change of the circuit and locate it accurately. It can be widely used in the nondestructive circuit testing and reliability evaluation.