Kinetic Monte Carlo simulation of growth of BaTiO3 thin film via pulsed laser deposition

Considering the characteristics of perovskite structure, a kinetic Monte Carlo（KMC） model, in which Born-Mayer- Huggins（BMH） potential was introduced to calculate the interatomic interactions and the bonding ratio was defined to reflect the crystallinity, was developed to simulate the growth of BaTiO3 thin film via pulsed laser deposition（PLD）. Not only the atoms deposition and adatoms diffusion, but also the bonding of adatoms were considered distinguishing with the traditional algorithm. The effects of substrate temperature, laser pulse repetition rate and incident kinetic energy on BaTiO3 thin film growth were investigated at submonolayer regime. The results show that the island density decreases and the bonding ratio increases with the increase of substrate temperature from 700 to 850 K. With the laser pulse repetition rate increasing, the island density decreases while the bonding ratio increases. With the incident kinetic energy increasing, the island density decreases except 6.2 eV〈Ek〈9.6 eV, and the bonding ratio increases at Ek〈9.6 eV. The simulation results were discussed compared with the previous experimental results.     

引入项目实施法的计算机实践教学

以高校的计算机教学与应用能力培养为切入点,基于导学制形式提出了一种全新的以学生为主体、以教师为主导、以梯队式开发应用项目作为实践平台的"教—学—应用"教学模式。此模式侧重学生的自主学习和全程参与,强调教师的启发式教学和实时性指导,重视计算机应用实践的有机渗透和教学活动的系统化开展。并基于教学模式与培养改革探索,进一步阐述了教与学互动、学与用互补的内在联系。