Using the method of Picus and Beer invariants, general expressions are obtained for the total intensity I and the degree of circular polarization Рcirc.of the luminescence of GaAs-type semiconductors with the partici...Using the method of Picus and Beer invariants, general expressions are obtained for the total intensity I and the degree of circular polarization Рcirc.of the luminescence of GaAs-type semiconductors with the participation of shallow acceptor levels in a longitudinal magnetic field H. Special cases are analyzed depending on the value and direction of the magnetic field strength, as well as on the constants of the g-factor of the acceptor g1,g2and the conduction band electron ge. In the case of a strong magnetic field H// [100], [111], [110], a numerical calculation of the angular dependence of the quantities I and Рcirc.was performed for some critical values of g2/g1, at which Рcirc.exhibits a sharp anisotropy in the range from −100% to +100%, and the intensity of the crystal radiation along the magnetic field tends to a minimum value.展开更多
Diamond negatively charged nitrogen-vacancy(NV-) centers provide an opportunity for the measurement of the Meissner effect on extremely small samples in a diamond anvil cell(DAC) due to their high sensitivity in detec...Diamond negatively charged nitrogen-vacancy(NV-) centers provide an opportunity for the measurement of the Meissner effect on extremely small samples in a diamond anvil cell(DAC) due to their high sensitivity in detecting the tiny change of magnetic field. We report on the variation of magnetic field distribution in a DAC as a sample transforms from normal to superconducting state by using finite element analysis. The results show that the magnetic flux density has the largest change on the sidewall of the sample, where NV-centers can detect the strongest signal variation of the magnetic field. In addition, we study the effect of magnetic coil placement on the magnetic field variation. It is found that the optimal position for the coil to generate the greatest change in magnetic field strength is at the place as close to the sample as possible.展开更多
We theoretically investigate the two-center interference in high-order harmonics generated from the H2-＋ in a combination of a mid-infrared laser and a terahertz field by numerically solving the time-dependent Schr &...We theoretically investigate the two-center interference in high-order harmonics generated from the H2-＋ in a combination of a mid-infrared laser and a terahertz field by numerically solving the time-dependent Schr ¨odinger equation（TDSE）.The interference minima in high-order harmonic generation（HHG） are effectively suppressed when a THz field is added.The contribution to HHG from the two separate nuclei is used to demonstrate the locating order of the harmonic minima.Furthermore, we also investigate the emission time of harmonics. The results show that the intensity of the short path around 60^th order after adding a THz field is stronger than that in the mid-infrared laser field, which further illustrates the suppression of the interference minima in HHG.展开更多
针对互联网数据中心(Internet Data Center,IDC)云计算基本内容、应用优势展开分析,探讨IDC云计算在计算资源调度、数据存储和处理、软件开发环节以及网络优化服务中的应用要点。通过分析IDC云计算在通信领域中的安全风险,提出IDC云计...针对互联网数据中心(Internet Data Center,IDC)云计算基本内容、应用优势展开分析,探讨IDC云计算在计算资源调度、数据存储和处理、软件开发环节以及网络优化服务中的应用要点。通过分析IDC云计算在通信领域中的安全风险,提出IDC云计算在通信领域资源层、应用层、平台层以及访问层的安全风险应对措施,以确保通信网络环境的稳定性与安全性。展开更多
文摘Using the method of Picus and Beer invariants, general expressions are obtained for the total intensity I and the degree of circular polarization Рcirc.of the luminescence of GaAs-type semiconductors with the participation of shallow acceptor levels in a longitudinal magnetic field H. Special cases are analyzed depending on the value and direction of the magnetic field strength, as well as on the constants of the g-factor of the acceptor g1,g2and the conduction band electron ge. In the case of a strong magnetic field H// [100], [111], [110], a numerical calculation of the angular dependence of the quantities I and Рcirc.was performed for some critical values of g2/g1, at which Рcirc.exhibits a sharp anisotropy in the range from −100% to +100%, and the intensity of the crystal radiation along the magnetic field tends to a minimum value.
基金supported by the National Key R&D Program of China(Grant No.2018YFA0305900)the National Natural Science Foundation of China(Grant Nos.11774126,11674404,and 51772125)
文摘Diamond negatively charged nitrogen-vacancy(NV-) centers provide an opportunity for the measurement of the Meissner effect on extremely small samples in a diamond anvil cell(DAC) due to their high sensitivity in detecting the tiny change of magnetic field. We report on the variation of magnetic field distribution in a DAC as a sample transforms from normal to superconducting state by using finite element analysis. The results show that the magnetic flux density has the largest change on the sidewall of the sample, where NV-centers can detect the strongest signal variation of the magnetic field. In addition, we study the effect of magnetic coil placement on the magnetic field variation. It is found that the optimal position for the coil to generate the greatest change in magnetic field strength is at the place as close to the sample as possible.
基金supported by the National Natural Science Foundation of China(Grant Nos.61575077,11574117,and 11271158)the Graduate Innovation Fund of Jilin University,China(Grant No.2016153)
文摘We theoretically investigate the two-center interference in high-order harmonics generated from the H2-＋ in a combination of a mid-infrared laser and a terahertz field by numerically solving the time-dependent Schr ¨odinger equation（TDSE）.The interference minima in high-order harmonic generation（HHG） are effectively suppressed when a THz field is added.The contribution to HHG from the two separate nuclei is used to demonstrate the locating order of the harmonic minima.Furthermore, we also investigate the emission time of harmonics. The results show that the intensity of the short path around 60^th order after adding a THz field is stronger than that in the mid-infrared laser field, which further illustrates the suppression of the interference minima in HHG.
文摘针对互联网数据中心(Internet Data Center,IDC)云计算基本内容、应用优势展开分析,探讨IDC云计算在计算资源调度、数据存储和处理、软件开发环节以及网络优化服务中的应用要点。通过分析IDC云计算在通信领域中的安全风险,提出IDC云计算在通信领域资源层、应用层、平台层以及访问层的安全风险应对措施,以确保通信网络环境的稳定性与安全性。
