BaTiO3铁电体中辐射位移效应的分子动力学模拟

运用基于壳模型的分子动力学方法研究了BaTiO₃铁电体中的辐射位移效应.采用O原子作为初级击出原子,模拟了当初级击出原子能量为1 keV时体系内缺陷的产生和演化.模拟结果表明,当入射方向为001]时,体系内产生的缺陷最多.在所有缺陷中,以O缺陷的含量为最高,达80%以上.同时,这些缺陷的产生并不显著改变体系的自发极化强度,对体系的极化翻转过程也基本没有影响.在外电场作用下,观察到了显著的缺陷迁移. 关键词： 分子动力学 3铁电体')" href="#">BaTiO₃铁电体 辐射位移效应

Molecular dynamics simulation of radiation displacement effect in BaTiO3 ferroelectrics

Radiation displacement effect is studied using shell model molecular dynamics simulations. Using oxygen atom as a primary knock-on atom, the creation and the evolution of various defects in the system corresponding to the primary knock-on atom(PKA) energy of 1 keV are studied. The results show that a largest number of defects are created when the incidence is along the 001]direction. Among all the defect species, oxygen atom defects are dominant, and its concentration reaches 80%. The creation of defects does not change the spontaneous polarization of the system significantly, and the polarization reversal also changes little. Defect migration is observed under an applied electric field.