Magnetic And Microwave Field Imaging Based On Ensemble NV Centers

With the development of scale,multilayer and integration of integrated circuits,there is a need to explore a high precision and high spatial resolution circuit tomography imaging technique.In recent years,diamond nitrogen-vacancy(NV)color centers have become a hot research topic in quantum sensing due to their excellent characteristics of stable crystal structure,high sensitivity,and high resolution at room temperature.Among them,the magnetic field detection technology based on diamond NV color centers has also made significant progress.Firstly,in this paper,based on the diamond NV center system integrated wide-field imaging system,the magnetic field laminarization measurement and inversion on the surface of a two-layer circuit is realized by imaging the magnetic vector intensity distribution on the surface of the two-layer integrated circuit.Direct current is passed through a double-layer integrated circuit placed on the diamond surface,and the resulting magnetic field is imaged with micron-level resolution using a technique based on continuous wave optically detected magnetic resonance(CW-ODMR).Accurate characterization of the magnetic field intensity in the 0-10.5 Gs range was achieved over a field of view of 2.4 mm × 1.35 mm and a depth range of 0.32 mm.Secondly,after obtaining the magnetic field image of the whole double-layer circuit and the magnetic field distribution of the upper layer,we finally isolate the magnetic field image of the lower energized wire by using the vector magnetic field superposition property.Combined with the Biot-Savart law,we can further inverse perform the magnetic field distribution image of the lower layer surface.Compared with the measurement results of the upper layer,the maximum magnetic field intensity error after inversion is about 0.4%,and the error of the magnetic field distribution after inversion is about 8%.In order to demonstrate the reliability of imaging,we also conducted simulation experiments.The experimental results show that the magnetic field distribution of the double-layer miniature integrated circuit is imaged accurately,and the precision quantum measurement technique of the multilayer miniature integrated circuit chip function provides effective support for the detection and fault diagnosis.Finally,to meet the demand for high-resolution,lossless,and fast wide-field imaging of microwave devices,this thesis also combines CW-ODMR technology with optical wide-field imaging technology to propose a wide-field microwave imaging method based on the tethered diamond NV center.The optimal selection of laser parameters is achieved by measuring different laser powers.Then the accuracy of the wide-field microwave imaging technique is demonstrated by measuring the near-field imaging of the antenna surface at different microwave input powers and different microwave input frequencies.