The features of optical defects in a chemical vapor deposition (CVD) synthetic type Ⅱ a diamond were characterized using photoluminescence (PL) spectroscopy, before and after electron irradiation. The sample was cut ...The features of optical defects in a chemical vapor deposition (CVD) synthetic type Ⅱ a diamond were characterized using photoluminescence (PL) spectroscopy, before and after electron irradiation. The sample was cut within a {100} growth layer, and irradiated with 2 MeV electrons along the <100> axis. PL spectra of sample were collected under 532 nm and 355 nm laser excitation, at room temperature and 77 K, and linear scanning analysis along incident depth was applied to determine the distribution of defects. The pre-irradiation characterization results revealed uniformly distributed PL centers at 389 nm, 469 nm, 533 nm, 575 nm (ZPL of NV 0), 637 nm (ZPL of NV -), and 736.7/737.1 nm (ZPL doublet of SiV -). After irradiation, the differential responses of these as-grown defects were observed, alongside the emergence of irradiation-induced defects, namely 489 nm center, H3 center (ZPL at 504 nm) and GR1 center (ZPL at 741 nm). The maximum penetration depth of 2 MeV electron-irradiation induced defects was determined to be 2.1 mm. This work primarily presents the depth profiles of both as-grown and irradiation-induced defects in 2 MeV electrons irradiated diamond. The result provides experimental data for better understanding of the radiation effect in diamonds. Serving as a reference for diamond enhancement by electron irradiation.展开更多
Comprehending the microscopic formation of nitrogen vacancy(NV)centers in nitrogen-doped diamonds is crucial for enhancing the controllable preparation of NV centers and quantum applications.Irradiation followed by an...Comprehending the microscopic formation of nitrogen vacancy(NV)centers in nitrogen-doped diamonds is crucial for enhancing the controllable preparation of NV centers and quantum applications.Irradiation followed by annealing simulations for a type-Ib diamond with a 900 ppm concentration of isolated nitrogen is conducted along different orientations and at different annealing temperatures.In these simulations,molecular dynamics(MD)with smoothly connected potential functions are implemented.MD simulations revealed the dynamic formation process of the NV center,which was subsequently verified by first-principles calculations and experiments.The results indicate that vacancies undergo one or multiple migrations by exchanging sites with neighboring atoms.There are three mechanisms for the formation of NV centers:direct irradiation-induced NV formation,irradiation with further annealing to form NV and vacancy migration(VM)during the annealing process.Furthermore,the results show that both VM and NV center formations are affected by orientations.This study clarifies the formation of NV centers across multiple scales and provides a solid foundation for the targeted preparation of NV centers.展开更多
基金This work is supported by National Natural Science Foundation of China(No.42372054)。
文摘The features of optical defects in a chemical vapor deposition (CVD) synthetic type Ⅱ a diamond were characterized using photoluminescence (PL) spectroscopy, before and after electron irradiation. The sample was cut within a {100} growth layer, and irradiated with 2 MeV electrons along the <100> axis. PL spectra of sample were collected under 532 nm and 355 nm laser excitation, at room temperature and 77 K, and linear scanning analysis along incident depth was applied to determine the distribution of defects. The pre-irradiation characterization results revealed uniformly distributed PL centers at 389 nm, 469 nm, 533 nm, 575 nm (ZPL of NV 0), 637 nm (ZPL of NV -), and 736.7/737.1 nm (ZPL doublet of SiV -). After irradiation, the differential responses of these as-grown defects were observed, alongside the emergence of irradiation-induced defects, namely 489 nm center, H3 center (ZPL at 504 nm) and GR1 center (ZPL at 741 nm). The maximum penetration depth of 2 MeV electron-irradiation induced defects was determined to be 2.1 mm. This work primarily presents the depth profiles of both as-grown and irradiation-induced defects in 2 MeV electrons irradiated diamond. The result provides experimental data for better understanding of the radiation effect in diamonds. Serving as a reference for diamond enhancement by electron irradiation.
基金Hubei Provincial Jewelry Engineering Technology Research Center,Gemological Institute,China University of Geosciences(Wuhan)for its support(Grant No.CIGTXM-04-S202301)The project was supported by the National Natural Science Foundation of China(Grant Nos.52302046 and 52202045)+4 种基金the Natural Science Foundation of Hubei Province(Grant No.2022CFB606)the Knowledge Innovation Program of Wuhan-Shuguang(Grant No.2023010201020255)the Fundamental Research Funds for the Central Universities(Grant Nos.2042023kf0116 and 2042023kf0112)the Fundamental Research Funds for National University,China University of Geosciences(Wuhan)(Grant No.CUGDCJJ202225)the Open Fund of Hubei Key Laboratory of Electronic Manufacturing and Packaging Integration(Wuhan University)(Grant No.EMPI2023016).
文摘Comprehending the microscopic formation of nitrogen vacancy(NV)centers in nitrogen-doped diamonds is crucial for enhancing the controllable preparation of NV centers and quantum applications.Irradiation followed by annealing simulations for a type-Ib diamond with a 900 ppm concentration of isolated nitrogen is conducted along different orientations and at different annealing temperatures.In these simulations,molecular dynamics(MD)with smoothly connected potential functions are implemented.MD simulations revealed the dynamic formation process of the NV center,which was subsequently verified by first-principles calculations and experiments.The results indicate that vacancies undergo one or multiple migrations by exchanging sites with neighboring atoms.There are three mechanisms for the formation of NV centers:direct irradiation-induced NV formation,irradiation with further annealing to form NV and vacancy migration(VM)during the annealing process.Furthermore,the results show that both VM and NV center formations are affected by orientations.This study clarifies the formation of NV centers across multiple scales and provides a solid foundation for the targeted preparation of NV centers.
