发表机构
LIPhy, Université Grenoble Alpes, CNRS（LIPhy，格勒诺布尔阿尔卑斯大学，法国国家科学研究中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究人员通过无热准静态模拟，以挤压作为局域探针，探究不同稳定性模型玻璃的力学响应，揭示其从弹性到塑性的转变及与玻璃稳定性的关联，为非晶固体研究提供新视角。
AI 中文摘要
我们采用具有不同稳定性程度的模型玻璃的无热准静态模拟，数值研究非晶固体对局部力偶（称为挤压）的力学响应。我们采用控制参数——施加的伸长量，对应于两个被挤压粒子的静止长度相对于其初始间距的增加。增大该伸长量可使系统从弹性 regime 连续调谐到塑性 regime。对于小伸长量，响应保持弹性，在此 regime 中，挤压诱导的位移场可由线性弹性很好地描述，且呈现与偶极力一致的长程幂律衰减。平均响应显示出各向异性的类四极图案，模拟与分析预测定量一致，该连续体描述在粒子尺度距离下仍然有效。随着施加的伸长量增大，响应变为塑性，挤压随后可触发局域化或系统级的重排，具体取决于玻璃稳定性：充分退火的玻璃表现出局域化的塑性事件，而退火不良的系统则表现出局域化的级联。我们引入一种提取塑性变形主轴的方法，并分析相关的位移场和塑性活动。总体而言，我们的结果表明，挤压为非晶固体提供了一种最小的局域探针，其产生的响应由玻璃稳定性和施加的伸长量共同支配，为理解弹性、基本重排与集体塑性的出现之间的相互作用提供了见解。
英文摘要
We numerically investigate the mechanical response of amorphous solids to localized force dipoles, referred to as pinching, using athermal quasistatic simulations of model glasses with varying degrees of stability. We employ a control parameter, the imposed extension, corresponding to the increase in rest length between the two pinched particles relative to their initial separation. Increasing this extension allows us to continuously tune the system from the elastic to the plastic regime. For small extensions, the response remains elastic. In this regime, the displacement field induced by pinching is well described by linear elasticity and exhibits a long-range power-law decay consistent with dipolar forcing. Averaged responses display anisotropic, quadrupolar-like patterns, with quantitative agreement between simulations and analytical predictions. This continuum description remains valid down to particle-scale distances. As the imposed extension increases, the response becomes plastic. Pinching can then trigger either localized or system-spanning rearrangements, depending on glass stability. Well-annealed glasses exhibit localized plastic events, whereas poorly annealed systems display delocalized cascades. We introduce a method to extract the principal axis of plastic deformation and analyze the associated displacement fields and plastic activity. Overall, our results demonstrate that pinching provides a minimal local probe of amorphous solids. The resulting response, governed by both glass stability and imposed extension, offers insight into the interplay between elasticity, elementary rearrangements, and the emergence of collective plasticity.
