Concentration Quantitative Analysis And Characterization Of NV Color Center Ensembles In Diamond

The NV color center in diamond is a defect structure consisting of a substitutional nitrogen atom(N)and an adjacent carbon vacancy(V)in diamond.Among them,NV-is stable at room temperature,and has long electron-coherence time,which can be controlled by laser and microwave.It is considered to be the most promising structure in the field of quantum sensing.Widely used in the measurement of weak magnetic fields,electric fields,stress,and physical quantities such as temperature,pressure,and spin.The density,uniformity and distribution of NV color centers in bulk diamonds are important parameters affecting the optical readout of NV color centers.The spectral detection method was used to accurately measure the concentration of NV color-centered microdomains in Ib-type diamond,and the uniformity and distribution of NV color centers were further calculated.The main contents of this paper are as follows:1.After electron irradiating the 100 planes of type Ib HTHP diamond in different doses,and them are annealing subjected in high temperature to obtain samples with different concentrations of NV color centers.The internal structure of the samples were examined by infrared spectroscopy.The concentration of NV color centers in samples after different irradiation doses was calculated by Raman spectroscopy analysis.2.Because the concentration of NV color centers in different parts of block diamond is not the same,this study proposes a method to accurately measure the distribution,concentration,and uniformity of NV color centers in samples using micro-photoluminescence spectroscopy.The 100 planes of four blocks of diamond were divided into 256 tiny areas,and the photoluminescence spectrum of each tiny area was read to analyze the significance of thecharacteristic peaks and phonon sidebands in the micro-photoluminescence spectrum.The peak position of the spectrum can be used to determine the charge state of the NV color center in the block diamond.Integrating the spectrum near the NV color center zero sound sub-band on the spectrum can calculate the concentration of the corresponding NV color center at that point.3.The distribution of NV color centers in diamond is analyzed by comparing the spectral data of each lattice and then the uniformity of the distribution of NV color centers over the entire 100 planes is calculated.The results show that the NV color center is not uniformly distributed within the diamond,and the concentration of the sample irradiated with electrons for 3h is the highest.The best uniformity of the sample was obtained after 2h electron irradiation.This study accurately measured the fluorescence spectral characteristics of the NV-color center in the 1.3 μm diameter region and the distribution and uniformity of the plane.This study provides basis for the preparation of quantitative and uniform distribution of NV color centers,and provides an effective reference for the characterization of the precise distribution of cluster NV-color centers in bulk diamond.