基于金刚石氮-空位色心的新型钢筋检测方法

Novel Rebar Detection Method Based on NV Color Center in Diamond

针对传统混凝土钢筋探测仪检测深度大多在100 mm以下且误差较大的问题,基于量子精密测量中金刚石氮-空位(NV)色心体系搭建了新型钢筋检测实验平台。金刚石NV色心因其优异的自旋性质和光学特性,对磁场有极高的分辨率。使用532 nm波长激光和微波对金刚石进行激光激发及微波调控,金刚石中的NV色心探测被测磁场,通过扫描光探测磁共振谱(ODMR)得到反射的微波功率,从而计算钢筋的尺寸及位置信息。结果表明自制的微波天线在2.87 GHz谐振频率下的回波损耗(S11)为-9.297 dB,在150 mm深度完成混凝土中钢筋位置、个数和直径的检测,钢筋位置平均误差≤4.3 mm,钢筋直径误差≤2.7 mm。

The detection depth of traditional concrete rebar detectors is mostly below 100 mm and the error is large.In order to solve the problem,an experimental platform was built based on the diamond nitrogen-vacancy(NV)color center system in quantum precision measurement.Due to its excellent spin properties and optical properties,the diamond NV color center has an extremely high resolution to the magnetic field.A 532 nm laser and microwave were used to laser excitation and microwave control of diamond,the NV color center in the diamond detected the magnetic field to be measured,the reflected microwave power was obtained by scanning optical detected magnetic resonance(ODMR)to calculated the size and position information of rebars.The results show that the return loss(S11)of the self-made microwave antenna at resonant frequency of 2.87 GHz is-9.297 dB.The detection of the positions,number and diameters of rebars in the concrete is completed at a depth of 150 mm,and the average error of the rebar position is≤4.3 mm,and the error of the rebar diameter is≤2.7 mm.