The Key Technology Of Solid-state Ensembles Spin Manipulation Under Microwave Field Of NV Centers In Diamond

As a new type of quantum system,the nitrogen-vacancy center in diamond has attracted more and more attentions because of its advantages of long coherence time at room temperature and easily to integrate.The nitrogen-vacancy(NV)center can be initialized and readout under the laser,additionally,the spin-state of the nitrogen-vacancy center can be manipulated under the microwave,the nitrogen-vacancy center in diamond has been considered as one of most promised candidate of spin carriers.The physical quantity of the magnetic field,temperature,electric field,and angular rate has been measured using a single NV color center.NV ensembles have stronger fluorescence and higher collection rate compared with the single NV center,the fluorescence collection method of NV ensembles is more simple,and it is the inevitable trend of future quantum sensing development.The NV ensembles are seriously affected by the surrounding environment which often results in rapid loss of coherence,so the spin manipulation of NV ensembles needs better microwave radiation performance and high precision timing control,it makes the spin manipulation of NV ensembles is more complicated.And the following studies were conducted:First,we have studied on both the properties of NV color center and the effect of microwave on the spin,the relationship between the microwave power and the resonance signal is obtained.At the same time,the principle of the spin manipulation of the NV center is studied.Second,we have designed a new type of microwave radiation antenna and optimized the structure of the antenna in order to improve the near-field performance,we compared the radiation performance of traditional copper wire and microstrip antenna by HFSS simulation,near field test and resonance signal test.The results show that the microstrip antenna is more predominant for the spin manipulation of the NV ensembles.Finally,we built a system to manipulate the spin of the NV ensembles.We have achieve the automation control through the PC software,it has the ability of high precision timing output and data acquisition.In conclusion,this work is the basis of spin manipulation of the NV ensembles by microwave field.,and it promotes the practical process of quantum sensing based on NV color center.