The Study On Quantum Manipulation Based On Different Current And Coupling Energy Transfer Mechanism Of NV Center In Nanodiamond

As a single photon source at room temperature with excellent optical performance,the NV center in diamond has been widely applied in quantum information technology,high-sensitivity detection technology,high-resolution imaging technology,bio-fluorescence labeling,etc.In addition,the diamond NV color center is a typical two-level structure.The ground state and the excited state are spin triplet states.The electronic transition is easily affected by external conditions.Therefore,the NV color center can also be used to conduct magnetic and electric fields and detect the surrounding electron spins.In the research or application of NV color center,the relevant information of color center is usually obtained according to its fluorescence spectrum,so it is very important to regulate the fluorescence of NV color center.In the experiment,the NV color center with the strongest light was prepared by changing the preparation conditions of nanometer diamond NV color center,including electron irradiation concentration,vacuum annealing temperature and time,and oxidation annealing temperature and time.After the single photon source of prepared NV color center is located by the established laser confocal microscopy system,there are two methods to regulate the fluorescence of the prepared NV color centers.On the one hand,the NV center single photon source can be coupled to graphene.In this process,energy is transferred from the NV color center to graphene in a non-radiative manner.As a result,the fluorescence intensity of NV excitation radiation was reduced.The fluorescence intensity of NV color center single photon source on graphene substrate is lower than that on silica substrate,which proves that energy transfer occured between NV color center single photon source and graphene,thus realizing quantum control of color center.It is expected to provide experimental basis for the development of high resolution microscopic imaging sensors.On the other hand,different electric currents are used to generate different electric fields,and the presence of applied electric fields will produce Stark effect on the NV color center,thus affecting the electronic transition of NV color center and improving the radiation efficiency of NV color center,so as to achieve the purpose of regulating the fluorescence of NV color center.After applying different currents to graphene,gold and n-type silicon substrates,the fluorescence spectra of NV color center on various substrates were tested and compared,and the fluorescence spectra of NV color center on different substrates also changed with the change of current,so as to achieve the purpose of regulating fluorescence of NV color center by current,which can provide some theoretical and experimental basis for the research and application of NV color center in the fields of quantum control,quantum information processing and highly sensitive detection.In addition,we also researched the effect of different laser power on the fluorescence of the NV center.It is found that increasing the power of the excitation light source can also significantly increase the fluorescence intensity of the NV color center.