Key Technology Studies Of Magnetometer Based On Ensembles Of NV Centers In Diamond

With the progress of science and technology,weak magnetic detection technology developed greatly in recent years.Negatively Nitrogen Vacancy(NV-)in diamond can satisfy the requirements of precision magnetic detection with high sensitivity as well as spatial resolution,at the same time,magnetometer based on NV centers has many inherent excellent properties such as small volume,long electron spin coherence time,wide temperature working range,high stability and fast startup time,and so on,whitch attracted the attention of many researchers.Studies found that the concentration and uniformity of NV centers,relaxation time,stimulation and collection efficiency are the most important factors affecting the performance of NV atomic magnetometer,researchers at home and abroad are doing research on the several key factors in recent years,in spite of the gains,no major breakthroughs were made.Therefore,the thesis mainly studies the controllable concentration preparation and characterization of NV ensembles,as well as DC magnetic measurement based on NV centers.the main research content and the results obtained are as follows:Firstly,we developed the NV ensembles controllable preparation technology,and obtained the relationship between different electron injection doses and the concentrations of NV centers,which provides a reference basis for subsequent quantitative preparation of NV centers.Secondly,we set up a home-made confocal platform,and use it to measure the electron spin resonance of NV ensembles under different magnetic field at room temperature,which established an excellent experimental conditions for the study of realizing the magnetic detection based on NV ensembles.Thirdly,we achieved the minimum static magnetic detection of 4.98 μT by utilizing NV ensembles through the CW-ESR method,which laid a foundation for further study of adopting pulse sequences to realizing higher magnetic detection.