论文标题
SRTIO3中变形诱导的位错的性质：来自原子模拟的见解
The nature of deformation-induced dislocations in SrTiO3: Insights from atomistic simulations
论文作者
论文摘要
长期存在的有争议的问题是，SRTIO3在SRTIO3中机械诱导的位错的性质长期存在。在这里，我们提供了化学计量SRTIO3中现有关于位错知识的系统概述，并由几种提出的脱位类型的计算模型补充。基于原子模拟，我们揭示了它们的结构和迁移率，并将重点放在部分脱位中，因为这种机制负责钛酸锶的良好脱位迁移率。我们的结果表明，由于滑行分离的构型，带有{1-10}滑行平面（A，B型）的位错（A型A，B和C）显示出易于滑行行为。然而，由于{1-1-1-2}滑行平面（D型D）的情况，{001}滑行平面（E型）上位错的运动被禁止。对于（部分）边缘特征的位错，将分离为部分的分离对位错核心的电荷状态非常敏感。反过来，脱位迁移率与位错解离密切相关，因此宏观延展性在某些情况下可能与位错核心的电荷有直接关系。
The nature of mechanically induced dislocations in SrTiO3 at low temperatures has been a disputed matter for a long time. Here we provide a systematic overview of the existing knowledge on dislocations in stoichiometric SrTiO3 complemented by computational models of several of the proposed dislocation types. Based on atomistic simulations we reveal their structure and mobility and put our focus on the splitting into partial dislocations, because this mechanism is held responsible for the good dislocation mobility in strontium titanate. Our results reveal that dislocations with a {1-10} glide plane (types A, B, and C) show easy glide behavior due to their glide dissociated configuration. The motion of dislocations on {001} glide planes (type E), however, is prohibited due to high Peierls barriers, as is the case for the {1-1-2} glide plane (type D). For dislocations with (partial) edge character the dissociation into partials is shown to be very sensitive to the charge state of the dislocation core. Since, in turn, dislocation mobility is strongly related to the dissociation of dislocations, the macroscopic ductility may in some cases have a direct relation to the charge at the dislocation core.
