The chirality-asymmetry macroscopic force mediated by light pseudoscalar particles between a-quartz and some achiral matter is studied. If this force between achiral source mass and a-quartz with some chirality is att...The chirality-asymmetry macroscopic force mediated by light pseudoscalar particles between a-quartz and some achiral matter is studied. If this force between achiral source mass and a-quartz with some chirality is attractive, it will become repulsive when the chirality of the a-quartz crystal is changed. According to the tested limits of the coupling constant gsgp/hc 〈 1.5×10^-24 at the Compton wavelength A = 10-3 m, the force （F） between a 0.08 × 0.08 × 0.002 m3 block of a-quartz and a 0.08 × 0.08× 0.01 m3 copper block with a separation being 0.5 × 10^-3 m in between, is estimated from the published data at less than 4.64 × 10^-24 N, i.e. F 〈 4.64 ×10^-24 N.展开更多
Our calculations demonstrate that the concentration of neutral oxygen vacancies can affect the geometrical structrue,electronic structure, and optical properties of α-quartz. Moreover, the distribution of the neutral...Our calculations demonstrate that the concentration of neutral oxygen vacancies can affect the geometrical structrue,electronic structure, and optical properties of α-quartz. Moreover, the distribution of the neutral oxygen divacancy can also exert some influence on the properties of α-quartz. The dissimilarity and similarities are presented in the corresponding density of state（DOS） and absorption spectrum. In addition, when a higher defect concentration is involved in α-quartz,the influence of E1 center on the geometry of α-quartz becomes more significant. However, the introduction of an E1 center barely results in any improvement compared with the influence produced by the corresponding neutral defect.展开更多
The latent ion track in α-quartz is studied by molecular dynamics simulations. The latent track is created by depositing electron energies into a cylindrical region with a radius of 3nm. In this study, the electron s...The latent ion track in α-quartz is studied by molecular dynamics simulations. The latent track is created by depositing electron energies into a cylindrical region with a radius of 3nm. In this study, the electron stopping power varies from 3.0keV/nm to 12.0keV/nm, and a continuous latent track is observed for all the simulated values of electron stopping power except 3.0keV/nm. The simulation results indicate that the threshold electron stopping power for a continous latent track lies between 3.0keV/nm and 3.7 keV/nm. In addition, the coordination defects produced in the latent track are analyzed for all the simulation conditions, and the results show that the latent track in α-quartz consists of an O-rich amorphous phase and Si-rich point defects. At the end of this paper, the influence of the energy deposition model on the latent track in α-quartz is investigated. The results indicate that different energy deposition models reveal similar latent track properties. However, the values of the threshold electron stopping power and the ion track radius are dependent on the choice of energy deposition model.展开更多
基金Project supported by the National Basic Research Program of China (Grant No 2003CB716300)the National Natural Science Foundation of China (Grant No 10121503)
文摘The chirality-asymmetry macroscopic force mediated by light pseudoscalar particles between a-quartz and some achiral matter is studied. If this force between achiral source mass and a-quartz with some chirality is attractive, it will become repulsive when the chirality of the a-quartz crystal is changed. According to the tested limits of the coupling constant gsgp/hc 〈 1.5×10^-24 at the Compton wavelength A = 10-3 m, the force （F） between a 0.08 × 0.08 × 0.002 m3 block of a-quartz and a 0.08 × 0.08× 0.01 m3 copper block with a separation being 0.5 × 10^-3 m in between, is estimated from the published data at less than 4.64 × 10^-24 N, i.e. F 〈 4.64 ×10^-24 N.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11176020 and 11374217)the Doctoral Program of Higher Education of China(Grant No.20100181110080)
文摘Our calculations demonstrate that the concentration of neutral oxygen vacancies can affect the geometrical structrue,electronic structure, and optical properties of α-quartz. Moreover, the distribution of the neutral oxygen divacancy can also exert some influence on the properties of α-quartz. The dissimilarity and similarities are presented in the corresponding density of state（DOS） and absorption spectrum. In addition, when a higher defect concentration is involved in α-quartz,the influence of E1 center on the geometry of α-quartz becomes more significant. However, the introduction of an E1 center barely results in any improvement compared with the influence produced by the corresponding neutral defect.
文摘The latent ion track in α-quartz is studied by molecular dynamics simulations. The latent track is created by depositing electron energies into a cylindrical region with a radius of 3nm. In this study, the electron stopping power varies from 3.0keV/nm to 12.0keV/nm, and a continuous latent track is observed for all the simulated values of electron stopping power except 3.0keV/nm. The simulation results indicate that the threshold electron stopping power for a continous latent track lies between 3.0keV/nm and 3.7 keV/nm. In addition, the coordination defects produced in the latent track are analyzed for all the simulation conditions, and the results show that the latent track in α-quartz consists of an O-rich amorphous phase and Si-rich point defects. At the end of this paper, the influence of the energy deposition model on the latent track in α-quartz is investigated. The results indicate that different energy deposition models reveal similar latent track properties. However, the values of the threshold electron stopping power and the ion track radius are dependent on the choice of energy deposition model.
