论文标题
振动模式的拓扑预测眼镜中的塑料事件
Topology of vibrational modes predict plastic events in glasses
论文作者
论文摘要
可以通过考虑其结构缺陷（例如脱节和位错）来理解晶体材料的塑性变形。尽管眼镜也是固体，但它们的结构与液体的结构非常相似，因此结构缺陷的概念变得不确定。因此，在微观水平上合理化的玻璃的机械性能是非常具有挑战性的，即接近屈服点的玻璃的机械性能，并将塑料事件与结构特性相关联。在这里，我们研究了二维玻璃模型的振动激发特征向量场的拓扑特征，尤其是拓扑缺陷的几何布置是振动频率的函数。我们发现，如果系统受到过准剪切的约束，则所得塑料事件的位置与具有负电荷的拓扑缺陷密切相关。因此，我们的结果提供了在玻璃结构之前的变形和变形过程中塑料事件之间的直接联系。
The plastic deformation of crystalline materials can be understood by considering their structural defects such as disclinations and dislocations. Although glasses are also solids, their structure resembles closely the one of a liquid and hence the concept of structural defects becomes ill-defined. As a consequence it is very challenging to rationalize on a microscopic level the mechanical properties of glasses close to the yielding point and to relate plastic events with structural properties. Here we investigate the topological characteristics of the eigenvector field of the vibrational excitations of a two-dimensional glass model, notably the geometric arrangement of the topological defects as a function of vibrational frequency. We find that if the system is subjected to a quasistatic shear, the location of the resulting plastic events correlate strongly with the topological defects that have a negative charge. Our results provide thus a direct link between the structure of glasses prior their deformation and the plastic events during deformation.
